Title: Portable / Without sound / Psychology / Gray - Psychology
Tags: definitions questions chapter2 chapter3 chapter1

Q: absolute threshold
A: In psychophysics, the faintest (lowest-intensity) stimulus of a given sensation (such as sound or light) that an individual can detect.

Q: accommodation
A: In Piaget's theory of cognitive development, the change that occurs in an existing mental scheme or set of schemes as a result of the assimilation of the experience of a new event or object.

Q: action potentials
A: Neural impulses; the all-or-nothing electrical bursts that begin at one end of the axon of a neuron and move along the axon to the other end.

Q: activating effect of sex hormones
A: Temporary, reversible effects that sex hormones have on sexual drive.

Q: additive color mixing
A: The mixing of colored lights by superimposing them to reflect off the same surface.

Q: Attention defitic/hyperactivity disorder
A: A frequently diagnosed disorder in children, characterized by impulsiveness and difficulties in focusing attention on tasks.

Q: Affect
A: A noun referring to any emotional feeling.

Q: aggression
A: Fighting and threats of fighting among members of the same species.

Q: Alleles
A: Different genes that can occupy the same locus on a pair of chromosomes and thus can potentially pair with one another.

Q: altruism
A: In sociobiology, a type of helping behavior in which an individual increases the survival chance or reproductive capacity of another individual while decreasing its own survival chance or reproductive capacity.

Q: Alzheimer's disease
A: A disorder found primarily in the elderly, characterized by progressive deterioration in cognitive functioning and the presence of deposits in the brain referred to as amyloid plaques.

Q: amplitude
A: The amount of physical energy or force exerted by a physical stimulus at any given moment.  For sound, this physical measure is related to the psychological experience of loudness.

Q: Amygdala
A: A brain stucture that is part of the limbic system and is particularly important for evaluating the emotional and motivational significance of stimuli and generating emotional responses.

Q: analogy
A: In ethology and comparative psychology, any similarity among species that is not due to common ancestry but has evolved independently because of some similarity in their habitats or lifestyles.

Q: androgen
A: A category of hormones, including testosterone, which are produced by the testes in male animals and are normally thought of as "male hormones".  These hormones are also produced at lower levels by the adrenal glands, in females as well as in males.

Q: anterograde amnesia
A: Loss, due to injury to the brain, in ability to form new long-term memories for events that occur after the injury.

Q: anxiety disorders
A: The class of mental disorders in which fear or anxiety is the most prominent symptom.  It includes generalized anxiety disorder, obsessive-compulsive disorder, panic disorder, phobias, and postraumatic stress disorder.

Q: aphasia
A: Any loss in language ability due to brain damage.

Q: arcuate nucleus
A: A nucleus in the hypothalamus that plays a critical role in the control of appetite.

Q: arousability
A: In discussions of sexuality, the capacity to become sexually aroused in response to sexually relevant stimuli.

Q: artificial selection
A: The deliberate selective breeding of animals or plants by humans for the purpose of modifying the genetic makeup of future generations.

Q: assimilation
A: In Piaget's theory of cognitive development, the process by which experiences are incorporated into mental schemes.

Q: association
A: Concerning the mind, a link between two ideas, such that recall of one tends to promote recall of the other.

Q: association areas
A: Areas of the cerebral cortex that receive input from the primary or secondary sensory areas for more than one sensory modality (such as vision and hearing) and are involved in associating this input with stored memories, in the processes of perception, thought, and decision making.

Q: association by contiguity
A: The principle, originally proposed by Aristotle and adopted by the British empiricists that two stimuli occurring simultaneously or contiguously will be linked together in the mind.

Q: association by similarity
A: Aristotle's principle that ideas similar to one another become associated in the person's mind.

Q: attachment
A: The long-lasting emotional bonds that infants develop toward their principal caregivers.  More broadly, the long-lasting emotional bonds that any individual develops toward any other individual or object.

Q: attention
A: In the modal model of the mind, the process that controls the flow of information from the sensory store into working memory. More broadly, any focusing of mental activity along a specific track, whether that track consists purely of inner memories and knowledge or is based on external stimuli.

Q: attitude
A: Any belief or opinion that has an evaluative component--a belief that something is good or bad, likable or unlikable, attractive or repulsive.

Q: attribution
A: In social cognition, any inference about the cause of a person's behavioral action or set of actions.  More generally, any inference about the cause of any observed action or event.

Q: Auditory masking
A: The phenomenon by which one sound (usually a lower-frequency sound) tends to prevent the hearing of another sound (usually a higher-frequency sound).

Q: autism
A: A congenital (present-at-birth) disorder, typically marked by severe deficits in social interaction, severe deficits in language acquisition, a tendency to perform repetitive actions, and a restricted focus of attention and interest.

Q: autonomic portion of the peripheral motor system
A: The set of motor neurons that act upon visceral muscles and glands.

Q: availability bias
A: Tendency, in reasoning, to rely too much on information that is readily available to us and to ignore information that is less available.

Q: axon
A: A thin, tubelike extension from a neuron that is specialized to carry neural impulses (action potentials) to other cells.

Q: axon terminal
A: A swelling at the end of an axon that is designed to release a chemical substance (neurotransmitted) onto another neuron, muscle cell, or gland cell.

Q: basal ganglia
A: The Large masses of gray matter in the brain that lie on each side of thalamus; they are especially important for the initiation and coordination of deliberate movements.

Q: basilar membrane
A: A flexible membrane in the cochlea of the inner ear; the wavelike movement of this structure in response to sound stimulates the receptor cells for hearing.

Q: behavior
A: The observable actions of an individual person or animal.

Q: behavior therapy
A: Category of treatment methods that use basic principles of learning in order to weaken unwanted behavioral responses or strengthen desired behavioral responses.

Q: behavioral genetics
A: Research specialty that attempts to explain psychological differences among individuals in terms of differences in their genes.

Q: bejavioral neuroscience
A: Research specialty that attempts to explain behavior in terms of processes occurring within the nevrous system.

Q: behaviorism
A: A school of psychological thought that holds that the proper subject of study is observable behavior, not the mind, and that behavior should be understood in terms of its relationship to observable events in the environment rather than in terms of hypothetical events within the individual.

Q: bias
A: A technical term referring to nonrandom (directed) effects on research results, caused by some factor or factors extraneous to the research hypothesis.

Q: biased sample
A: A subset of the population under study that is not representative of the population as a whole.

Q: binocular disparity
A: The cue for depth perception that stemps from the separate (disparate) views that the two eyes have of any given visual object or scene. The farther away the object is, the more similar are the two views of it.

Q: bipolar cells
A: The class of neurons in the retina that receive input from the receptor cells (rods and cones) and form synapses on ganblion cells (which form the optic nerve).

Q: Bipolar disorders
A: Mood disorders that are characterized by episodes of abnormally high mood (mania) and abnormally low mood (depression).

Q: bipolar I disorder
A: The most severe type of bipolar disorder, characterized by at least one episode of mania and one episode of major depression.

Q: bipolar II diosrder
A: The typoe of bipolar disorder in which the manic phase is less extreme than it is in Bipolar I disorder and is referred to as hypomania rather than mania.

Q: blind
A: In scientific research, the condition in which those who collect the data are deliberately kept uninformed about aspects of the study's design (such as which subjects have had which treatments) that could lead them either unconsciously or consciously to bias the results.

Q: blind spot
A: The place in the retina of the eye where the axons of visual sensory neurons come together to form the optic nerve.  Because the blind spot lacks receptor cells, light that strikes it is not seen.

Q: blood-brain barrier
A: The tight capillary walls and the surrounding glial cells that prevent many chemical substances from entering the brain from the blood.

Q: bottom-up control
A: In theories of perception, mental processes that bring the individual stimulus features recorded by the senses together to form a perception of the larger object or scene.

Q: brainstem
A: The primitive, stalklike portion of the brain that can be thought of as an extension of the spinal cord into the head; it consists of the medulla, pons, and midbrain.

Q: Broca's aphasia
A: A specific syndrome of loss in language ability that occurs due to damage in a particular part of the brain called Broca's area; it is characterized by telegraphic speech in which the meaning is usually clear but the small words and word endings that serve grammatical purposes are missing.

Q: cell body
A: The widest part of a neuron, which contains the cell nucleus and the other basic machinery common to all cells.

Q: cell membrane
A: The thin, porous outer covering of a neuron or other cell that separates the cell's intracellular fluid from extracellular fluid.

Q: central drive system
A: According to the central-state theory of drives, a set of neurons in the brain that, when active, most directly promotes a specific motivational state, or drive.

Q: central executive
A: In Baddeley's theory, a component of the mind responsible for coordinating all the activities of working memory and for bringing new information into working memory.

Q: central nervous system
A: The brain and spinal cord.

Q: central-state theory of drives
A: The theory that the most direct physiological bases for motivational states, or drives, lie in neural activity in the brain. According to most versions of this theory, different drives correspond to activity in different, localizable sets of neurons.

Q: cerebellum
A: The relatively large, conscpicuous, convoluted portion of the brain attached to the rear side of the brainstem; it is especially important for the coordination of rapid movements.

Q: cerebral cortex
A: The outermost, evolutionarily newest, and (in humans) by far the largest portion of the brain; it is divisible into two hemispheres (right and left), and each hemisphere is divisible into four lobes--the occipital, temporal, parietal, and frontal.

Q: chromosomes
A: The structures within the cell nucleus that contain the genetic material (DNA).

Q: chunking
A: A strategy for improving the ability to remember a set of items by grouping them mentally to form fewer items.

Q: circadian rythm
A: Any cyclic physiological or behavioral change in a person or other living thing that has a period of asbout 1 day even in the absence of external cues signaling the time of day.

Q: classical conditioning
A: A training procedure of leraning experience in which a neutral stimulus (the conditioned stimulus) comes to elicit a relfexive response thorugh its being paired with another stimulus (usually an unconditioned stimuls) that already elicits that reflexive response.

Q: clinical psychology
A: The field of practice and research that is directed toward helping people who suffer from psychological problems and disorders.

Q: cochlea
A: A coiled structure in the inner ear in which the receptor cells for hearing are located.

Q: cognitive-behavior therapy
A: The psychotherapy approach that stems from a union of cognitive and behavioral theory; it usually characterizes psychological problems as learned habits of thought and action, and its approach to treatment is to help people change those habits.

Q: cognitive dissonance theory
A: Festinger's theory that people seek to relieve the discomfort associated with the awareness of inconsistency between two or more of one's own cognitions.

Q: cognitive psychology
A: Research specialty that attempts to explain behavior or mental experiences in terms of the cognitions (items of mental information or knowledge) that underlie the behavior or experience.

Q: cognitive therapy
A: An approach to psychotherapy that begins with the assumption that people disturb themselves through their own thoughts and that they can overcome their problems through changing the way they think about their experiences.

Q: concept
A: A rule or other form of mental information fr categorizing stimuli into groups.

Q: concordance
A: In behavioral genetics research, an index of heritability that is found by identifying a set of individuals who have a particular trait or disorder and then determining the precentage of some specific class of their relatives (such as identical twins) who have the same trait or disorder.

Q: concrete-operational scheme
A: In Piaget's theory, the type of mental stimulus that allows a child to think logically about reversible actions (operations) bu tonly when applied to objects with which the child has had direct (concrete) experience.

Q: conditioned reflex
A: In classical conditioning, a reflex that occurs only because of previous conditions in the individula's experience; a learned reflex.

Q: conditioned response
A: In classical conditioning, a reflexive response that is elicited by a stimulus (the conditioned stimulus) because of the previous pairing of that stimulus with another stimulus (the unconditioned stimulus) that already elicists a reflexive response.

Q: conditioned stimulus
A: In classical conditioning, a stimulus that comes to elicit a reflexive response (the conditioned response) because of its previous pairing with another stimulus (the unconditioned stimulus) that already elicits a reflexive response.

Q: cones
A: The class of receptor cells for vision that are located in and near tha fovea of the retina, operate in moderate to bright light, and are most important for the perception of color and fine detail.

Q: cone vision
A: The high-acuity color vision that occurs in moderate to bright light and is mediated by cones in the retina.

Q: confirmation bias
A: Tendency of people to seek evidence that confirms, rather than disconfirms, their current hypotheses.

Q: consciousness
A: In perception, the experience of percepts or other mental events in such a manner that one can report on them to others.

Q: consolidation
A: The process by which a new memory becomes solidified in the brain, such that it is not easily forgotten.

Q: content morphemes
A: Words, including nouns, verbs, adjetctives, and adverbs, that are most essential to the meaning of a sentence.

Q: contingency mangament
A: In behavior therapy, any systematic alteration in the relationship (contingency) between actions and rewards that is designed to alter the clients behavior in a desired direction.

Q: control processes
A: In the modal model of the mind, the mental processes that operate on information in the memory stores and move information from cone store to another.

Q: conversion disorder
A: A category of somatoform disorder in which the person, for psychological reasons, loses som e bodily function.

Q: cooperation
A: In sociobiology, a type of helping behavior in which interaction among two or more individuals increases the survival chance or reproductive capacity of each individual involved in the interaction.

Q: cornea
A: The curved, transparent tissue at the front of the eyeball that helps to focus light rays as the first enter the eye.

Q: corpus callosum
A: A massive bundle of axons connecting the right and left hemispheres of the higher parts of the brain, including the cerebral cortex.

Q: correlation coefficient
A: A numerical measure o the strength and direction of the relationship between two variables.

Q: correlational study
A: Any scientific study in which the researcher observes or measures (without directly manipulating) two or more variables to find relationships between them.  Such studies can identify lawful relationships but cannot determine whether change in one variable is the cause of change in another.

Q: cranial nerve
A: A nerve that extends direclty from the brain.

Q: creole language
A: A new language, with grammatical rules, that develops from a pidgin language in colonies established by people who had different native languages.

Q: critical period
A: A relatively restricted time period in an individual's development during which a particular form of learning can best occur.

Q: cyrstallized intelligence
A: In Cattell's theory, the variety of intelligence that derives directly from previous experience.  It includes ones accumulated knowledge and verbal skills.

Q: cultural psychology
A: Research specialty that attempts to explain mental experiences and behavior in terms of the culture in which the person developed it.

Q: dark adaptation
A: The increased visual sensitivity that occurs when the eyes are exposed for a period of time dto dimmer light than was present before the adaptation period.

Q: deductive reasoning
A: Logical reasoning from the general to the specific; the reasoner begins by accepting the truth of one or more general premises or axioms and uses them to assert whether a specific conclusion is true, false, or indeterminate.

Q: defense mechanisms
A: In psychoanalytic theory, self-deceptive means by which the mid defends itself against anxiety.

Q: dendrites
A: The thin, tubelike extensions of a neuron that typically branch repeatedly near the neuron's cell body and are specialized for receiving signals from other neurons.

Q: dependent variable
A: In an experiment, the variable that is believed to be dependent upon (affected by) another variable (the independent variable).  In psychological experiments, it is usually some measure of behavior.  When changes in variables are represented graphically, it is conventional to plot variation in the dependent variable along the vertical axis.

Q: depressive disorders
A: The class of mood disorders characterized by prolonged or frequent bouts of depression.

Q: descriptive statistics
A: Mathematical methods for summarizing sets of data.

Q: descriptive study
A: Any study in which the researcher describes the behavior of an individual or set of individuals without systematically investigating relationships between specific variables.

Q: deterministic fallacy
A: The mistaken belief that genes control, or determine, behavior in a manner that is indepdendent of environmental influences.

Q: developmental psychology
A: The branch of psychology that charts changes in people's abilities and styles of behaving as they get older and tries to understand the factors that produce or influence those changes.

Q: difference threshold
A: In psychophysics, the minimal difference that must exist between two otherwise similar stimuli for an individual to detect them as different.

Q: differential lighting of surfaces
A: A pictorial cue for perceiving depth in which the amount of light reflecting on different surfaces indicates the position of objects relative to the light source.

Q: differentiating effects of sex hormones
A: Effects of sex hormones that create the long-lasting structural differences between males and females of a species.

Q: discrimination training
A: The procedure, in both classical and operant conditioning, by which generalization between two stimuli is diminidhsed or abolished by reinforcing the response to one stimulus and extinguishing the response to the other.

Q: discriminative stimulus
A: In operating conditioning, a stimulus that serves as a signal that a particular response will produce a particular reinforcer.

Q: displacement
A: The defense mechanism by which a drive is diverted from one goal to another that is more realistic or acceptable.  Also called sublimation in cases where the goal toward which the drive is diverted is highly valued by society.

Q: dominant gene
A: A gene that produces its observable effects even if the person is heterozygous for that gene (that is, has that gene allele on only one of the two paired chromosomes).

Q: dopamine
A: One of many neurotransmitter substances in the brain.  It is, among other things, crucial for the "wanting" component of reward.

Q: double-blind experiment
A: An experiment in which both the observer and the subjects are blind with respect to the subjects  treatment conditions.

Q: Down syndrome
A: A disorder that results from having an extra chromosome 21, characterized by a specific set of physical symptoms and moderate to severe retardation in intellectual functioning.

Q: drug tolerance
A: The phenomenon by which a drug produces succesively smaller physiological and behavioral effects, at any given dose, if it is taken repeatedly.

Q: DSM-IV
A: Commonly used abbreviation for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, published by the American Psychiatric Association, which defines a wide variety of mental disorders and establishes criteria for diagnosing them.

Q: dualism
A: The philosophical theory that two distinct systems--the material body and the immaterial soul--are involved in the control of behavior.

Q: dysthymia
A: A mental disorder characterized by feelings of depression that are less severe than those in major depression but which last for at least a 2-year period.

Q: echoic memory
A: Sensory memory for the sense of hearing.

Q: elaboration
A: The process of thinking about an item of information in such a way as to tie the item mentally to other information i memory, which helps to encode the item into long-term meory.

Q: elaboration likelihood model
A: A theory of persuasion postulating that people are more likely to think logically about a message (that is, elaborate upon the message) if it is personally relevant that if it is not.

Q: electroconvulsive therapy (ECT)
A: A procedure for treating severe depression, in which a patient is anesthesized ang diven a muscle relaxant, n then an electric rurent is passed through the patient's skull in such a way as to set up a seizure either in one hemisphere of the brain (unilateral ECT) or in both hemispheres.

Q: emotion
A: A subjective feelings that is experienced as directed toward some particular object or event.

Q: empiricism
A: The idea that all human knowledge and thought ultimately come from sensory experience; the philosophical approach to understanding the mind that is based on that idea.

Q: encoding
A: In the modal model of the mind, the mental process by which long-term memories are formed.

Q: encoding rehearsal
A: Any active mental process by which a person strives to encode information into long-term memory.

Q: endorphins
A: Chemicals produced in the body that act like morphine in inhibiting pain.

Q: episoding memory
A: Explicit memory of past events (episodes) in one's own life.

Q: error
A: A technical term referring to random variability in research results.

Q: evolutionary psychology
A: Research specialty that attempts to explain how or why specific behavioral characteristics would have come about, by natural selection, in the course of evolution.

Q: excitatory synapse
A: A synapse at which the neurotransmitter increases the likelihood that an action potential will occur, or increases the rate at which they are already occurring, in the neuron on which it acts.

Q: experiment
A: A research design for testing hypotheses about cause-effect relationships, in which the researcher manipulates one variable (the independent variable) in order to assess its effect on another variable (the dependent variable).

Q: explicit attitudes
A: Conscious attitudes; that is, attitudes that people are aware of holding and can state verbally.

Q: explicit memory
A: The class of memory that can be consciously recalled and used to answer explicit questions about what one knows or remembers.

Q: explicit stereotypes
A: Stereotypes that people hold consciously

Q: exposure treatment
A: Any method of treating fears--including flooding and systematic desensitization-that involves exposing the client to the feared object or situation (either in reality or imagination) so that the process of extinction or habituation of the fear response can occur.

Q: extinction
A: In classical conditioning, the gradual disappearance of a conditioned reflex that results when a conditioned stimulus occurs repeatedly without the unconditioned stimulus. In operant conditioning, the decline in response rate that results when an operant response is no longer followed by a reinforcer.

Q: fact
A: An objective statement, usually based on direct observation, that reasonable observers agree is true.  In psychology, facts are usually particular behaviors, or reliable patterns of behaviors, of persons or animals.

Q: factor analysis
A: A statistical procedure for analyzing the correlations among various measurements *such as test scores) taken from a given set of individuals; it identifies hypothetical, underlying variables called factors that could acount for the observed pattern of correlations and assesses the degree to which each factor is adequately measured by each of the measurements that was used in the analysis.

Q: feature detector
A: In vision, any neuron in the brain that responds to a specific property of a visual stimulus, suich as its color, orientation, movement, or shape of its contour. More generally, any neuron in the brain that responds to a particular property *feature) of any sensory stimulus.

Q: Fechner's law
A: The idea that the magnitude of the sensory experience of a stimulus is directly proportional to the logarithm of the physical magnitude of the stimulus.

Q: field study
A: Any scientific research study in which data are collected in a setting other than the laboratory.

Q: figure
A: In perception, the portion of a visual scene that draws the perceiver's attention and is interpreted as an object rather than as the background.

Q: five-factor model of personality
A: Model holding that a person's personality is most efficiently described in terms of his or her score on each of five relatively independent global trait dimensions: neuroticism, extraversion, openess to experience, agreeableness, and conscientiousness.

Q: fixed-interval (FI) schedule
A: In operant conditioning, a schedule of reinforcement in which a fixed period of time must elapse after each reinforced response before it produces a reinforcer.

Q: fixed-ratio (FR) schedule
A: In operant conditioning, a schedule of reinforcement in which a response must be produced a certain fixed number of times (more than once) before it produces a reinforcer.

Q: fluid intelligence
A: In Cattell's theory, the variety of intelligence that enables one to perceive relationships independent of previous specific practice or instruction concerning those relationships.

Q: floot-in-the-door technique
A: A technique for gaining compliance in which one first asks for some relatively small contribution or favor before asking for a larger one.  Complying with the first requests predisposes the person to comply with the second.

Q: formal-operational scheme
A: In Piagets theory, the type of mental stimulus that allows a person to reason about abstract concepts and hypothetical ideas.

Q: fovea
A: The pinhead-size area of the retina of the eye in which the cones are concentrated and that is specialized for high visual acuity.

Q: fraternal twins
A: Two individuals who developed simultaneously in the same womb, but who originated from separate zygotes (fertilized eggs) and are therefore no more genetically similar to one another than are nontwin siblings.

Q: free association
A: In psychoanalysis, the procedure in which a patient relaxes, frees his or her mind from the costraints of conscious logic, and reports every image and idea that enters his or her awareness.

Q: frequency
A: For any form of energy that changes in a cycli of wave-like way, the number of cycles or waves that occur during a standard unit of time. For sound, this physical measure is related to the psychological experience of pitch.

Q: frequency distribution
A: A table or graph depicting the number of individual scores, in a set of scores, that fall within each of a set of equal intervals.

Q: frontal lobe
A: THe frontmost lobe of the cerebral cortex, bounded in the rear by the parietal and temporal lobes; it contains the motor area and parts of the association areas involved in planning and making judgments.

Q: functionalism
A: A school pf psychological thought, founded by William James and others, that focuses on understanding the functions, or adaptive purposes, of mental processes.

Q: functional magnetic resonance imaging (fMRI)
A: A method for visually displaying brain activity that is based on the fact that protons in certain molecules can be made to resonate and give off radio waves indicating relative amounts of neural activity in each portion of the brain.

Q: ganglion cells
A: The sensory neurons for vision; their cell bodies are located in the retina, and their axons run by way of the optic nerve into the brain.

Q: gate-control theory
A: Melzack and Wall's theory that pain will be experienced only if the input from peripheral pain neurons passes through a "gate" located at the point that the pain-carrying neurons enter the spinal cord or lower brainstem.

Q: gaze following
A: The automatic, reflexive action by which one individual's eyes move when another individual's eyes move, so that both end up looking at the same object.

Q: gender identity
A: A person's subjective sense of being male or female.

Q: general intelligence
A: In SPearman's theory of intelligence (and in other theories based on Spearman's), the underlying mental ability that affects performance on a wide variety of mental tests and accounts for the statistical correlation among scores on such tests.

Q: generalization
A: In classical conditioning, the phenomenon by which a stimulus that resembles a conditioned stimulus will elicit the conditioned response even though it has never been paired with the unconditioned stimulus. In operant conditioning, the phenomenon by which a stimulus that resembles a discriminative stimulus will increase the rate at which the animal produces the operant reponse, even though the response thas never been reinforced in the presence of that stimulus.

Q: generalized anxiety disorder
A: A mental disorder characterized by prolonged, severe anxiety that is not consitently associated in the person's mind with any particular object or event in the environment or any specific life experience.

Q: genotype
A: The set of genes inherited by the individual.

Q: Gestalt principles of grouping
A: The rules, proposed by Gestalt psychologists, concerning the manner by which the perceptual system groups sensory elements together to produce organized perceptions of whole objects and scenes. They include the principles of (a0 proximity (neraby elements are grouped together), (b) similarity (elements that resemble one another are grouped together), (c) closure (gaps in what would otherwise be a continuous border are ignored), (d) good continuation (when lines intersetct, those segments that would form a continuous lines with minimal change in direction are grouped together), (e) common movement (elements moving in the same direction and velocity are grouped together), and (f) good form (elements are grouped in such a way as to form percepts that are simple and symmetrical.

Q: Gestalt psychology
A: A school of psychological thought, founded in Germany, which emphasizes the idea that the mind must be understood in terms of organized wholes, not elementary parts.

Q: grammar
A: The entire set of rules that specify the permissible ways that smaller units can be arranged to form morphemes, words, phrases, and sentences in a language.

Q: grammatical morphemes
A: The class of words, suffixes, and prefixes that serve primarily to fill out the grammatical structure of a sentence rather than to carry its main meaning.

Q: ground
A: In perception, the portion of a visual scene that is interpreted as the background rather than as the object of attention.

Q: group polarization
A: The tendency for a group of people who already share a particular opinion to hold that opinion more strongly--or in a more extreme form--after discussing the issue among themselves.

Q: groupthink
A: A model of tinking in which members of a group are more concerned with group cohesiveness and unanimity than with realistic appraisal of the actions being considered.

Q: habituation
A: The decline in the magnitude or likelihood of a reflexive response that occurs when the stimulus is repeated several or many times in succession.

Q: hair cells
A: The receptor cells for hearing, which are arranged in rows along the basilar membrane of the cochlea in the inner ear.

Q: helping
A: In sociobiology, any behavior that increases the survival chance or reproductive capacity of another individual.

Q: heritability
A: The proportion of the variability in a particular characteristic, in a particular group of individuals, that is due to genetic rather than environmental diffeerences among the individuals.

Q: heritability coefficient
A: A measure of heritability, which can vary from 0 (no heritability) to 1 (complete heritability); specifically, variance due to genes divided by total variance.

Q: heterozygous
A: The condition in which a pair of genes occupying the same locus on a pair of chromosomes are different from one another.

Q: hippocampus
A: A structure in the limbic system of the brain that is essential for encoding explicit memories for long-term storage.

Q: homeostasis
A: The constancy in the body's internal environment that must be maintained thorugh the expenditure of energy.

Q: homology
A: In ethology and comparative psychology, any similarity among species that exists because of the species' common ancestry.

Q: homozygous
A: The condition in which a pair of genes occupying the same locus on a pair of chromosomes are identical to one another.

Q: hormone
A: Any chemical substance that is secreted naturally by the body into the blood and can influence physiological processes at specific target tissues (such as the brain) and thereby influence behavior.

Q: humanistic theories
A: Personality theories that attempt to focus attention on the whole, unique person, especially on the person's conscious understanding of his or her self and the world.

Q: humanistic therapy
A: Any of several types of psychotherapy that emerged from humanistic personality theories, usually emphasizing the client's own constructions of his or her reality.

Q: hypothalamus
A: A small brain structure lying just below the thalamus, connected directly to the pituitary gland and to the limbic system, that is especially important for the regulation of motivation, emotion, and the internal physiological conditions of the body.

Q: hypothesis
A: A specific prediction abbout what will be observed in a research study, usually derived from a more general conception or theory.

Q: iconic memory
A: Sensory memory for the sense of vision.

Q: identical twins
A: Two individuals who are genetically identical to one another because they originated from a single zygote (fertilized egg); also called monozygotic twins.

Q: implicit association tests
A: Tests of a person's automatic, unconscious mental associations, designed to assess implicit stereotypes or other implicit attitudes.

Q: implicit attitudes
A: Attitudes that are manifested in a person's behavior or automatic mental associations, even though the person may not be conscious of holding those attitudes.

Q: implicit memory
A: Memory that influences ones behavior or thought but does not itself enter consciousness.

Q: implicit stereotypes
A: Stereotypes that autonamtically, unconsciously influence peoples judgments and actions toward others.

Q: impression management
A: The entire set of ways by which people either consciously or unconsciously attempt to influence other people's impressions (perceptions and judgements) of them.

Q: imprinting
A: Ethologists' term for a relatively sudden and irreversible form of learning that can occur only during some critical period of the individual's development.

Q: independent variable
A: In an experiment, the condition that the researcher varies in order to assess its effect upon some other variable (the dependent variable). In psychology, it is usually some condition of the environment or of the organism's physiology that is hypothesized to affect the individual's behavior.  When changes in variables are represented graphically, it is conventional to plot variation in the independent variable along the horizontal axis.

Q: inductive reasoning
A: Logical reasoning from the specific to the general; the reasoner begins with a set of specific observations or facts and uses them to infer a more general rule to account for those observations or facts.

Q: inferential statistics
A: Mathematical methods for helping researchers determine how confident they can be in drawing general conclusions (inferences) from specific sets of data.

Q: informational influence
A: The class of social influence that derives from the use of others' behavior or opinions as information in forming one's own judgment about the objective nature of an event or situation.

Q: inhibitory synapse
A: A synapse at which the neurotransmitter decreases the likelihood that an action potential will occur, or decreases the rate at which they are already occurring.

Q: inner ear
A: The portion of the ear lying farthest inward in the head; it contains the cochlea (for hearing) and the vestibular apparatus (for the sense of balance).

Q: insight problem
A: A problem that is difficult to solve until it is viewed in a new way, involving a different mental set from that originally taken.

Q: insufficient-justification effect
A: A change in atitude that serves to justify an action that seems unjustified in the light of the previously held attitude.

Q: intelligence
A: The variable mental capacity that underlies individual differences in reasoning, solving problems, and acquiring new knowledge.

Q: interneuron
A: A neuron that exists entirely within the brain or spinal cord and carries messages from one set of neurons to another.

Q: IQ
A: Abbreviation for intelligence quotient, defined as a score on a test of intelligence that is standardized in such a way that the average score for the population is q00 and the distribution of scores around that average matches a normal distribution.

Q: iris
A: The colored (usually brown or blue), doughnut-shaped, muscular structure in the eye, located behind the cornea and in front of the lens, that controls the size of the pupil and in that way controls the amount of light that can enter the eye's interior.

Q: kin selection theory of altruism
A: The sociobiological theory that apparent acts of altruism have come about through natural selection because such actions are disproportionately directed toward close genetic relatives and thus promote the survival of others who have the same genes.

Q: laboratory study
A: Any research study in which the subjects are brought to a specially designated area (laboratory) that has been set up to facilitate the researchers ability to control the environment or collect data.

Q: language-acquisition device (LAD)
A: Chomsy's term for the special, innate characteristics of the human mind that allow children to learn their native language; it includes innate knowledge of basic apsects of grammar that are common to all languages and an innate predisposition to attend to and remember the critical, unique aspects of the language.

Q: language-acquisition support system (LASS)
A: The term used by social-learning theorists to refer to the simplification of language and the use of gestures that occur when parents or other language users speak to young children, which helps children learn language; developed as a complement to Chomsky's concept of the lAD (language-acquisition device).

Q: latent learning
A: Learning that is not demonstrated in the subject's behavior at the time that the learning occurs but can be inferred from its effect on the subject's behavior at some later time.

Q: law of complementarity
A: The observation hat certain pairs of limited-wavelength lights that produce different colors (such as red and green) alone will produce the perception of white (no color) when mixed.

Q: law of effect
A: Thorndike's principle that responses that produce a satisfying effect in a particular situation become more likely to recur in that situation, and responses that produce a discomforting effect become less likely to recur in that situation.

Q: learning
A: The process or set of processes through which sensory experience at one time can affect an individula's behavior at a future time.

Q: learning psychology
A: Research specialty, in psychology, that attempts to understand how the behavior of individuals is shaped through basic learning processes.

Q: lens
A: In the eye, the transparent structure behind the iris that helps focus light that passes through the pupil.

Q: leptin
A: A hormone produced by fat cells that acts in the brain to inhibit hunger and regulate body weight.

Q: level of analysis
A: The type ("level") of causal process that is referred to in explaining some phenomenon.  In psychology a given type of behavior might be explained at the neural, genetic, evolutionary, learning, cognitive, social, cultural, or developmental level of analysis.

Q: light adaptation
A: The decreased visual sensitivity that occurs when the eyes are exposed for a period of time to brighter light than was present before the adaptation period.

Q: limbic system
A: An interconnected set of brain structures (including the amygdala and hippocampus) that form a circuit wrapped around the thalamus and basal ganglia, underneath the cerebral cortex. The structures are especially important for the regulation of emotion and motivation and are involved in the formation of long-term memories.

Q: linear perspective
A: A pictorial cue for perceiving depth in which the convergence of parallel lines indicates the distance of objects.  Parallel lines appear to converge as they become more distant.

Q: linguistic relativity
A: Whorf's theory that people who have different native languages perceive the world differently and think differently from each other because of their different languages.

Q: locus
A: In genetics, a position on a chromosome that contains the DNA of a single gene.

Q: locus of control
A: According to Rotter, a person's perception of the typical source of control over rewards. Internal locus of control refers to the perception that people control their own rewards through their own behavior, and external locus of control refers to the perception that rewards are controlled by external circumstances or fate.

Q: long-term memory
A: In the modal model of the mind, information that is retained in the mind for long periods )(often throughout life).

Q: long-term potentiation (LTP)
A: A process by which repeated activation of synapses results in strengthening of those synapses.

Q: loudness
A: The quality of the psychological experience (sensation) of a sound that is most directly related to the amplitude of the physical sound stimulus.

Q: low-ball technique
A: A sales trick in which the salesperson suggests a low price for the item being sold, and then, when the potential customer has agreed to buy it at that price, pretends to discover that the item cannot be sold for that price.

Q: maintenance rehearsal
A: Any active mental process by which a person strives to hold information in short-term memory for a period of time.

Q: major depression
A: A mental disorder characterized by severe depression that lasts essentially without remission for at least 2 weeks.

Q: materialism
A: Hobbe's theory that nothing exists but matter and energy.

Q: mean
A: The arithmetic average of a set of scores, determined by addding the scores and dividing the sum by the number of scores.

Q: medial forebrain bundle
A: A bundle of neurons that runs from the midbrain to the basal ganglia and other forebrain areas.

Q: median
A: The center score in a set of scores that have been rank-ordered.

Q: medulla
A: The lowest portion of the brainstem, bounded at one end by the spinal cord and at the other by the pons.  It is responsible, with the pons, for organizing reflexes more complex than spinal reflexes.

Q: meiosis
A: The form of cell division involved in producing egg or sperm cells, which results in cells that are genetically dissimilar and that each have half the number of chromosomes of the original cell.

Q: memory
A: 1. The mind's ability to retain information over time.
2. Information retained in the mind over time.

Q: memory stores
A: In cognitive psychology, hypothetical constructs that are conceived as places where information is helf in the mind.

Q: mental diorder
A: A disturbance in a person's emotions, drives, thought processes, or behavior that (a) involves serious and relatively prolonged distress and/or impairment in ability to function, (b) is not simply a normal response to some event or set of events in the person's environment, and (c) is not explainable as an effect of poverty, prejudice, or other social forces that prevent the person from behaving adaptively, nor as a deliberate decision to act in a way that is contrary to the norms of society.

Q: mental set
A: A habit of perception or thought, stemmimg from previous experience, that can either help or hinder a person in solving a new problem.

Q: midbrain
A: The upper portion of the brainstem, bounded at its lower end by the pons and at its upper end by the thalamus, that contains neural centers that organize basic movement patterns.

Q: middle ear
A: The air-filled cavity separated from the outer ear by the eardrum; its main structures are three ossicles (tiny bones) that vibrate in response to sound waves and stimulate the inner ear.

Q: mind
A: 1. The entire set of an individual's sensations, perceptions, memories, thoughts, dreams, motives, emotional feelings, and other subjective experiences.
2. In cognitive psychology, the set of hypothesized information-processing steps that analyze stimulus information and organize behavioral responses.

Q: mirror neurons
A: Neurons in the brain that become active both when the individual makes a particular motion and when the individual sees another individual making that same motion.  These neurons are believed to facilitate observational learning.

Q: mitosis
A: The form of cell division involved in normal body growth, which produces cells that are genetically identical to each other.

Q: modal model of the mind
A: A depiction of the mind as a set of memory storage compartments and control processes for manipulating and moving information. It has long served as the standard framework for thinking about the human mind.

Q: mode
A: The most frequently occurring score in a set of scores; in a frequency distribution, the interval that contains the highest frequency of scores.

Q: monogamy
A: A mating system in which one female and one male bond only with each other.

Q: mood
A: A free-floating emotional feeling, not directed at a specific object.

Q: moon illusion
A: The illusion by which the moon appears larger when seen near the horizon and smaller when seen near the zenith.

Q: morphemes
A: The smallest meaningful units of a verbal language; words, prefixes, or suffices that have discrete meanings.

Q: motion parallax
A: The cue for depth perception that stems from the changed view one has of a scene or object when one's head moves sideways to the scene or object; the frather away an object is, the smaller is the change in view.

Q: motivation
A: The entire constellation of factors, some inside the organism and some outside, that cause and individual to behave in a particular way at a particular time.

Q: motivational state
A: An internal, reversible condition in an individual that orients the individual toward one or another type of goal (such as food or water). This condition is not observed directly but is inferred from the individual's behavior; also called a drive.

Q: motor neuron
A: A neuron that carries messages from the brain or spinal cord, through a nerve, to a muscle or gland.

Q: Müller-Lyer illusion
A: A visual size illusion in which a horizontal line looks longer if attached at each end to an outward-extending, V-shaped object, and looks shorter if attached at each end to an inward-extending, V-shaped object.

Q: mutations
A: Erros that occasionally and unpredictably occur during DNA replication, producing a "replica" that is different from the original.  Mutations are believed to be the original source of all genetic variablity.

Q: myelin sheath
A: A casing of fatty cells wrapped tightly around the axon of some neurons.

Q: nativism
A: The idea that certain elementary ideas are innate to the human mind and do not need to be gained through experience; the philosophical approach to understanding the mind that is based on that idea.

Q: natural selection
A: The selective breeding that results from the obstacles to reproduction that are imposed by the natural environment; it is the driving force of evolution.

Q: naturalistic fallacy
A: The mistaken belief that whatever is natural (and particularly whatever is a product of natural selection) is right, good, or moral.

Q: naturalistic observation
A: Any data-collection procedure in which the researcher records subjects' ongoing behavior in a natural setting, without interfering with that behavior.

Q: nature-nurture debate
A: The long0standing controversy as to whether the differences among people are principally due to their genetic differences (nature) or differences in their past and present environment (nurture).

Q: negative contrast effect
A: In operant conditioning, the decline in response rate, when the size of a reinforcer (or reward) is reduced, to a rate below that which occurs for subjects that had been receiving the smaller reinforcer all along.

Q: negative punishment
A: In operant conditioning, the type of punishment in which the removal of a stimulus (such as taking foor or moeny) when a response occurs decreases the likelihood that the response will recur.

Q: negative reinforcement
A: In operant conditioning, the condition in which a response results in removal of a negative reinforcer.

Q: negative reinforcer
A: In operant conditioning, a stimulus )such as electric shock or loud noise) that is removed after a response and whose removal increases the likelihood that the response will recur.

Q: nerve
A: A large bundle containing the axons of many neurons. Located in the peripheral nervous system, nerves connect the central nervous system with muscles, glands, and sensory organs.

Q: neurohormone
A: A chemical substance that is similar to a neuro-transmitter in that it is secreted from the axon terminals of neurons but is clased as a hormone because it is secreted into blood vessels rather than onto other neurons.

Q: neuromodulators
A: Slow-acting neurotransmitters that do not directly alter the electrical charges across post-synaptic neurons, but, instead alter the manner by which post-synaptic neurons respond to fast-acting neurotransmitters.

Q: neurons
A: Single cells in the nervous system that are specialized for carrying information rapidly from one place to another and/or integrating information from various sources; also called nerve cells.

Q: neuropeptide Y
A: Neurotransmitter that acts in the brain to stimulate appetite.

Q: nonregulatory drive
A: Any motivational state that serves some function other than that of preserving some constancy of the body's internal environment.

Q: non-REM sleep
A: Stages 2, 3, and 4 of sleep, characterized by the occurrence of slow(delta) waves in the EEG and the lack of rapid eye movements.

Q: normal distribution
A: A bell-shaped frequency distribution in which the mean, median and mode are identical and the frequency of scores tapers off symmetrically on both sides, as defined by a specific mathematical equation.

Q: normative influence
A: The class of social influence that derives from people's concern about what others will think of them if they behave in a certain way or express a certain belief.

Q: nucleus
A: In neuroanatomy, a cluster of cell bodies of neurons within the central nervous system (not to be confused with the cell nucleus within each cell).

Q: nucelus accumbens
A: A nucleus (center of neural cell bodies) in the basal ganglia that is a crucial part of the brain's reward mechanism.

Q: object permanence
A: Piaget's term for the understanding that an object still exists even when it is out of view.

Q: observational learning
A: Learning by watching others.

Q: observational method
A: Any data-collection procedure in which the researcher directly observes the behavior of interest rather than relying on subjects' self-descriptions.

Q: obsessive-compulsive disorder
A: A mental disorder characterized by a repeated, disturbing, irrational thought (the obsession) that can only be terminated (temporarily) by performing some action (the compulsion).

Q: occipital lobe
A: The rearmost lobe of the cerebral cortex, bounded in front by the temporal and parietal lobes; it contains the visual area of the brain.

Q: occlusion
A: A pictorial cue or perceiving depth in which the closer object occludes (cuts off) part of the iew of the more distant object.

Q: operant conditioning
A: A training or learning process by which the consequence of a behavioral response affects the likelihood that the individual will produce that response again; also called instrumental conditioning.

Q: operant response
A: Any behavioral response that produces some reliable effect on the environment that influences the likelihood that the individual will produce that response again; also called instrumental response.

Q: operation
A: Piaget's term for a reversible action that can be performed either in reality or mentally upon some object or set of objects. For example, rolling a clay ball into a clay sausage is an operation, because the sausage can be rolled back again to form the ball.

Q: opponent-process theory of color vision
A: A theory designed by Hering to explain the law of complementarity, it holds that units (neurons) that mediate the perception of color are excited by one range of wavelengths and inhibited by another (complementary) range of wavelengths.  According to the theory, such units cancel out the perception of color when two complementary wavelength ranges are superimposed.

Q: optic nerve
A: The cranial nerve that contains the sensory neurons for vision, which run from the eye's retina into the brain.

Q: outer ear
A: The pinna (the visible, external portion of the ear) and the auditory canal (the air-filled opening that extends inward from the pinna to the middle ear).

Q: overjustification effect
A: The phenomenon in which a person who initially performs a task for no reward (except the enjpyment of the task) becomes less likely to perform that task for no reward after a period during which he or she has been rewarded for performing it.

Q: panic disorder
A: A mental disorder characterized by the repeated occurrence of panic attacks at unpredictable times and with no clear relationship to environmental events.  Each attack involves an intense feeling of terror, which usually lasts several minutes and is accompanied by signs of high physiological arousal.

Q: parallel processing
A: In perception, the early (unconscious) steps in the analysis of sensory information that act simultaneously on all (or at least many) of the stimulus elements that are available at any given moment.

Q: parasympathetic division of the autonomic motor system
A: The set of motor neurons that act upon visceral muscles and glands and mediate many of the body's regenerative, growth-promoting, and energy-conserving functions.

Q: parental investment
A: The time, energy, and risk to survival involved in producing, feeding, and otherwise caring for each offspring.

Q: parietal lobe
A: The lobe of the cerebral cortex that lies in front of the occipital lobe, above the temporal lobe, and behind the frontal lobe; it contains the somatosensory area of the brain.

Q: partial reinforcement
A: In operant conditioning, any condition in which the response sometimes produces a reinforcer and sometimes does not.

Q: pattern generators
A: Networks of neurons that stimulate one another in a cyclic manner and thereby produce bursts of action potentials that wax and wane in a regular, repeating rhythm.  They help to control rhythmic sequences of muscle movements, such as those involved in wakling, running, flying (in birds), or swimming (in fish).

Q: percentile rank
A: For any single score in a set of scores, the percentage of scores in the set that are equal to or lower than that score.

Q: perception
A: The recognition, organization, and meaningful interpretation of sensory stimuli

Q: peripheral nervous system
A: The entire set of cranial and spinal nerves that connect the central nervous system (brain and spinal cord) to the body's sensory organs, muscles, and glands.

Q: perpetuating causes of a mental disorder
A: Those consequences of a mental disorder--such as the way other people treat the person who has it--that help keep the disorder going once it begins.

Q: person bias
A: The tendency to attribute a person's behavior too much to the person's inner characteristics (personality) and not enough to the environmental situation.  Sometimes called the fundamental attribution error.

Q: person-centered therapy
A: The humanistic approach to psychotherapy (also called client-centered therapy) developed by Carl ROgers, in which the therapist generally refrains from offering advice or leading the course of therapy, but rather listens to the client with empathy and respect and reflects the client's thoughts and feelings back to him or her.

Q: personal identity
A: The portion of the self-concept that pertains to the self as a distinct, separate individual.

Q: personal myth
A: The ever-changing self-told story of an individual that gives a sense of direction and meaning to one's life.

Q: personality
A: The relatively consistent patterns of thought, feeling, and behavior that characterize each person as a unique individual.

Q: phenomenological reality
A: Humanistic theorists' term for each person's conscious understanding of his or her world.

Q: phenotype
A: The observable properties of an individual's body and behavior.

Q: pheromone
A: A chemical that is released by an animal and that acts on conspecifics to promote some specific behavioral or physiological response.

Q: phobia
A: Any mental disorder characterized by a strong, irrational fear of some particular category of object or even.

Q: phonemes
A: The various vowel and consonant sounds that provide the basis for a spoken language.

Q: phonological loop
A: In Baddeley's theory, a component of working memory responsible for holding verbal information.

Q: photoreceptors
A: Specialized light-detecting cells connected to the nervous system in many multicellular anials.  In humans and other vertebrates, the photoreceptors are rods and cones.

Q: pictorial cues for depth perception
A: The depth cues that operate not only when viewing real scenes but also when viewing pictures.  They inlcude occlusion, relative image size for familiar objects, linear perspective, texture gradient, differential lighting of surfaces, and (for outdoor scenes) position relative to the horizon.

Q: pidgin language
A: A primitive system of communication that emerges when people with different native languages colonize the same region; it uses words from the various native languages and has either no or minimal grammatical structure.

Q: pitch
A: The quality of the psychological experience (sensation) of a sound that is most related to the frequency of the physical sound stimulus.

Q: placebo
A: In drug studies, an inactive substance given to subjects assigned to the nondrug group.  More generally, any treatment that alters a person's behavior or feelings through the power of suggestion.

Q: polyandry
A: A mating system in which one female bonds with more than one male.

Q: polygenic characteristic
A: Any trait or characteristic for which the observed variation is affected by many genes.

Q: polygynandry
A: A mating system in which members of a group consisting of more than one male and more than one female mate with each other.

Q: polygyny
A: A mating system in which one male bonds with more than one female.

Q: pons
A: The portion of the brainstem that is bounded at its lower end by the medulla and its upper end by the midbrain and is responsible, with the medulla, for organizing reflexes more complex than spinal reflexes.

Q: Ponzo illusion
A: A visual size illusion in which two converging lines cause objects between the two lines to look larger near the converging ends of the lines and smaller near the diverging ends.

Q: position relative to the horizon
A: A pictorial cue for perceiving depth in which objects nearer the horizon seem farther away than objects displaced from the horizon.

Q: positive contrast effect
A: In operant conditioning, the increase in response rate, when the size of the reinforcer (or reward) is increased, to a rate that increases above that which occurs for subjects that had been receiving the larger reinforcer all along.

Q: positive punishment
A: In operant conditioning, the type of punishment in which the presentation of a stimulus (such as an electric shock or scolding) when a response occurs decreases the likelihood that the response will recur.

Q: positive reinforcement
A: In operant conditioning, the condition in which a response results in a positive reinforcer.

Q: positive reinforcer
A: In operant conditioning, a stimulus (such as food or money) that is presented after a response and that increases the likelihood that the response will recur.

Q: positron emission tomography (PET)
A: A method for visually displaying brain activity that is based upon the uptake of a radioactive form of oxygen into active areas of the brain.

Q: posttraumatic stress disorder
A: A mental disorder that is directly and explicitly tied to a particular traumatic incident or set of incidents (such as torture) that the affected person has experienced.

Q: preattentive processing
A: The analysis, at an unconscious level, in which the mind determines which stimuli are worth passing into working memory.

Q: precipitatig causes of a mental disorder
A: The events that most immediately bring on a mental disorder in a person who is sufficiently predisposed for the disorder.

Q: predictable-world bias
A: Tendency to believe that events are more predictable than they actually are.

Q: predisposing causes of a mental disorder
A: Those conditions that are in place well before the onset of a mental disorder and that make the person susceptible to the disorder.  They may include genetic predisposition, early childhood experiences, and the sociobultural environment in which one develops.

Q: prefrontal cortex
A: The front-most portion of the frontal lobe of the brain's cerebral cortex.

Q: premotor areas
A: Portions of the brain's cerebral cortex that lie directly anterior to (in front of) the motor area.  They provide neural programs for producing organized movements.

Q: preoperational scheme
A: In Piaget's theory, mental structures that permit the child to symbolize structures that permit the child to symbolize objects and events that are absent but do not permit the child to think about the operations that can be performed on objects.

Q: primary motor area
A: An area in the rear part of the frontal lobe of the cerebral cortex that is directly involved in the control of movements, especially finely coordinated movements of small muscles, as in the fingers and vocal apparatus.

Q: primary sensory areas
A: Specialized areas of the cerebral cortex that receive input from sensory nerves and tracts by way of the relay nuclei in the thalamus.  They include the visual area (in the occipital lobe), auditory area (in the temporal lobe), and somatosensory area (in the parietal lobe).

Q: primary visual area
A: The area in the rearmost part of the occipital lobe that receives input from the optic nerves (by way of the thalamus) and sends output to other visual-processing areas of the brain.

Q: priming
A: The implicit memory process by which a stimulus (the priming stimulus) activates (makes more retrievable) one or more memories that already exist in a person's mind.

Q: prisoner's dilemma games
A: A class of laboratory games in which the tendency to compete can be pitted against the tendency to cooperate.  In such games, the highest combined payoff to the two players occurs if both choose the cooperative response, but the highest individual payoff goes to a player who chooses the competitive response on a play in which the other chooses the cooperative response.

Q: procedural memory
A: The class of implicit memory that enables a person to perform specific elarned skills or habitual responses.

Q: peroceptivity
A: In discussions of sexuality, refers to ones motivation to seek out and initiate sexual activity, even when sexually arousing stimuli are not already present.

Q: projection
A: The defense mechanism by which a person consciously experiences his or her own unconscious emotion or wish as though it belongs to someone else or to some part of the environment.

Q: proximate explanations
A: Explanations of behavior that state the immediate environmental conditions or the mechanisms within the individual that cause the behavior to occur.

Q: psychoanalysis
A: 1. The theory of the mind developed by Freud, which emphasizes the roles of unconscious mental processes, early childhood experiences, and the drives of sex and aggression in personality formation; also called psychoanalytic theory.
2. Freu's therapy technique in which such methods as free association, dream analysis, and analysis of transference are used to learn about the person's unconscious mind; the goal is to make the unconscious conscious.

Q: psychodynamic theories of personality
A: Any theory that describes personality and its development in terms of inner mental forces that are often in conflict with one another and are shaped by experiences in early childhood.

Q: psychodynamic therapy
A: Any approach to psychotherapy that is based on the premise that psychological problems are manifestations of inner mental conflicts and that conscious awareness of those conflicts is a key to recovery.

Q: psychophysics
A: The scientific study of the relationship between physical characteristics of stimuli and the psychological experiences they induce.

Q: psychosurgery
A: The surgical cutting or production of lesions in a portion of the brain to relieve a mental disorder.

Q: psychotherapy
A: Any formal, theory-based, systematic treatment for mental problems or disorders that uses pshycological means (such as dialogue or training) rather than physiological means (such as drugs) and is conducted by a trained therapist.

Q: punishment
A: In operant conditioning, the process through which the consequence of a response decreases the liklihood that the response will recur.

Q: pupil
A: The hole in the center of the iris of the eye through which light passes.

Q: PYY
A: Abbreviation for peptide Y3-36, which is an appetite-suppressing hormone produce by cells in the small intestine.

Q: rationalization
A: The defense mechanism by which a person uses conscious reasoning to justify or explain away his or her harmful or irrational behaviors or thoughts.

Q: reaction formation
A: The defense mechanism by which the mind turns a frightening wish into its safe opposite.

Q: receptor potential
A: The electrical change that occurs in a receptor cell (such as a rod or cone in the eye, or a hair cell in the inner ear) in response to the energy of a physical stimulus (such as light or sound).

Q: recessive gene
A: A gene tha tproduces its observable effects only if the individual is homozygous for that gene (that is, has that gene allele on both of the two paired chromosomes).

Q: reciprocity norm
A: The widespread sense of obligation that people have to return favors.

Q: reciprocity theory of altruism
A: The sociobiological theory that apparent acts of altruism have come about through natural selection because they are actually forms of long-term cooperation rather than true altruism.

Q: reference group
A: A group of people with whom an individual compares himself or herself for the purpose of self-evaluation.

Q: reflex
A: A somple, relatively automatic, stimulus-response sequence mediated by the nervous system.

Q: regulatory drive
A: Any motivational state (such as hunger or thirst) that helps maintain some constancy of the body's internal environment that is necessary for survival.

Q: reinforcement
A: In operant conditioning, the presentation of a positive reinforcer or removal of a negative reinforcer when a response occurs, which increases the likelihood that the subject will repeat the response.

Q: reinforcer
A: In operant conditioning, any stimulus change that ocurs after a response and tends to increase the likelihood that the response will be repeated.

Q: relative image size for familiar objects
A: A pictorial cue for perceiving depth in which one infers the distance of familiar objects on the basis of their known actual sizes and the size of their retinal images.

Q: reliability
A: Degree to which a measurement system produces similar results each time it is used with a particular subject or set of subjects under a particular set of conditions. Regarding diagnoses of disorders, the degree to which different diagnosticians, all trained in the use of the diagnostic system, reach the same conclusions when they independently diagnose the same individuals.

Q: REM (rapid-eye-movement) sleep
A: The recurring stage of sleep during which the EEG resembles that of an alert person, rapid eye movements occur, the large muscles of the body are most relaxed, and true dreams are most likely to occur.  It is sometimes called emergent stage 1.

Q: repression
A: The defense mechanism by which the mind prevents anxiety-provoking ideas from becoming conscious.

Q: resistance
A: Attempts by a patient to avoid bringing unconcsious memories or wishes into consciousness.

Q: response
A: Any well-defined behavioral action, especially one that is elicited by some form of environmental stimulation or provocation.

Q: resting potential
A: The sonstant electrical charge that exists across the membrane of an inactive neuron.

Q: retina
A: A thin membrane of cells that lines the rear interior of the eyeball; it contains the receptor cells for vision (rods and cones).

Q: retrieval
A: In the modal model of the mind, the mental process by which long-term memories are brought into working memory, where they become part of the flow of thought.

Q: retrieval cue
A: A word, phrase, or other stimulus that helps one retrieve a specific item of information from long-term memory.

Q: retrograde amnesia
A: Loss, due to injury to the brain, of long-term memories that had been formed before the injury.

Q: reversible figure
A: A visual stimulus (usually a picture) in which any given part is seen sometimes as the figure and other times as the ground.

Q: rhodopsin
A: A The photochemical in rods that undergoes structural changes in response to light and thereby initiates the transduction process for rod vision.

Q: rods
A: The class of receptor cells for vision that are located in the peripheral portions of the retina (away from the fovea) and are most important for seeing in very dim light.

Q: rod vision
A: The low-acuity, high-sensitivity, noncolor vision that occurs in dim light and is mediated by rods in the retina of the eye.

Q: schema
A: The mental representation of a concept; the information stored in long-term memory that allows a person to identify a group of different events or items as members of the same category.

Q: schemes
A: Piaget's term for the mental entities that provide the basis for thought and that change in a stagelike way through development. They contain information about the actions that one can perform on objects, either in reality or symbolically in the mind.

Q: schizophrenia
A: A serious class of mental disorder that is characterized by disrtupted perceptual and thought processes, often including hallucinations and delusions.

Q: science
A: An approach to answering questions that is based on the systematic collection and logical analysis of objectively observable data.

Q: script
A: A variety of schema that represents in memory the temporal organization of a category of event (such as the sequence of occurrencesat a typical birthday party).

Q: selective breeding
A: The mating of those members of a strain of animals or plants that manifest a particular characteristic, which may or may not be done deliberately, to affect the genetic makeup of future generations of that strain; can be used to assess heritability.

Q: self-actualization
A: In humanistic psychology, the fulfillment of drives that go beyond one's survival needs and pertain to psychological growth, creativity, and self-expression.

Q: self-conscious emotions
A: The feelings of guilt, shame, embarrassment, and pride, which are linked to thoughts about the self or one's own actions.

Q: self-efficacy
A: A person's subjective sense of his own ability to perform a particular task or set of tasks.

Q: self-esteem
A: A person's feeling of approval and acceptance of himself or herself.

Q: self-report method
A: A data-collection method in which the people being studied are asked to rate or describe their own behaviors or mental states.

Q: self-serving attributional bias
A: The tendency of people to attribute their successes to their own qualities and their failures to the situation.

Q: semantic memory
A: Ones storehouse of explicit general knowledge, that is, of knowledge that can be expressed in words and is not mentally tied to specific experiences in one's own life.  Semantic memoty includes, but is not limited to, ones knowledge of word meanings.

Q: sensation
A: The psychological experience associated with a sound, light, or other simple stimulus and the initial information-processing steps by which sense organs and neural pathways take in stimulus information from the environment.

Q: sensorimotor scheme
A: In Piagets theory, the type of mental structure that enables an infant to act on objects that are immediately present but does not permit thought about objects that are absent.

Q: sensory adaptation
A: The temporary decrease in sensitivity to sensory stimulation that occurs when a sensory system is stimulated for a period of time, and the temporary increase in sensitivity that ocurs when a sensory system is not stimulated for a period of time.

Q: sensory areas of the cerebral cortex
A: Areas of the brain's cerebral cortex that receive and analyze input from the body's senses.  Separate sensory areas exist for each distinct sense.

Q: sensory coding
A: The process by which information about the quality and quantity of a stimulus is preserved in the pattern of action potentials sent through sensory neurons to the central nervous system.

Q: sensory memory
A: In the modal model of the mind, the moemry trace that preserves the original information in a sensory stimulus for a brief period (less that 1 secod for sights and up to 3 seconds for sounds) following the termination of the stimulus; it is experienced as if one is still sensing the original stimulus.

Q: sensory neuron
A: A neuron that carries messages from a sensory organ, through a nerve, into the brain or spinal cord.

Q: sensory receptors
A: Specialized biological structures--which in some cases are separate cells and in other cases are the sensitive tips of sensory neurons--that respond to physical stimuli by producing electrical changes that can initiate neural impulses (action potentials) in sensory neurons.

Q: sensory-specific satiety
A: The phenomenon by which a person or animal who is satiated on one food still has an appetite for another food that has a different taste.

Q: serial processing
A: The steps in the processing of sensory information that operate sequentially, an item at a time, on the available sensory information.

Q: shaping
A: An operant-conditioning procedure in which successively closer approximations to the desired response are reinforced until the response finally occurs.

Q: sibling contrast
A: Tendency to emphasize and exaggerate the differences between siblings.

Q: size constancy
A: The perceptual ability to see an object as the same size despite change in image size as it moves farther away or closer.

Q: skeletal portion of the peripheral motor system
A: The set of peripheral motor neurons that act upon skeletal muscles.

Q: social-cognitive theories of personality
A: Theories of personality that emphasize the roles of beliefs and habits of thought that are acquired through one's unique experiences in the social environment.

Q: social comparison
A: Any process in whcih an individual evaluates his or her oen abilities, characteristics, ideas, or achievements by comparing them with those of other people.

Q: social dilemma
A: A situation in which a particular action will (a) benefit the individual who takes it, (b) harm the individuals who don't, and (c) cause more harm than benefit to everyone if everyone takes it.

Q: social facilitation
A: The tendency to perform a task better in front of others than when alone.

Q: social identity
A: The portion of the self-concept that pertains to the social categories or groups of which the person is a part.

Q: social interference
A: The tendency to perform a task worse in front of others than when alone.

Q: social pain
A: The discomfort that people feel when they are socially rejected or when they lose a valued companion.

Q: social phobia
A: Any phobia in which the basic fear is of being scrutinized or evaluated by other people.

Q: social pressure
A: The entire set of psychological forces that are exerted on an individual by other people or by the individual's beliefs about other people.

Q: social psychology
A: The branch of psychology that attempts to understand how the behavior and subjective experiences of individuals are influenced by the actual or imagined presence of other people.

Q: social referencing
A: The process by which infants use the nonverbal emotional expressions of a caregiver as cues to guide their behavior.

Q: somatization disorder
A: A category of somatoform disorder that is characterized by vague, unverifiable complaints about many different medical conditions.

Q: somatoform disorders
A: The class of mental disorders in which the person experiences bodily ailments in the basence of any physical disease that could cause them.

Q: somatosensation
A: The set of senses that derive from the whole body--such as from the skin, muscles, and tendons--as opposed to those senses that come from the special sensory organs of the head.

Q: span of short-term memory
A: The number of pronounceable items of information (such as single, randomly chosen digits) that a person can retain in short-term (working) memory at any given time through rote rehearsal.

Q: species-typical behavior
A: Any behavior pattern that is so characteristic of a given species of animal that it can be used to help identify that species.

Q: specific phobia
A: Any phobia in which the feared object is a well-defined category of object (such as snakes) or environmental situations (such as heights) other than other people.

Q: spinal nerve
A: A nerve that extends directly from the spinal cord.

Q: split-parent identification
A: Tendency for each of two siblings to identify with a different one of their two parents.

Q: spontaneous recovery
A: In both classical and operant conditioning, the return--de to passage of time with no further testing or training--of a conditioned response that had previously undergone extinction.

Q: standard devitation
A: A measure of the variability in a set of scores, determined by taking the square root of the variance.

Q: standardized score
A: A score that is expressed in terms of the numer of standard deviations the original score is from the mean of the original scores.

Q: statistical significance
A: A statistical statement of how small the likelihood is that an obtained result occurred by chance.  By convention, research findings are said to be statistically significant if the probability is less than 5 percent that the data could have come out as they did if the research hypothesis were wrong.

Q: stereotypes
A: Mental concepts by which people characterize speicifc groups or categories of people.

Q: stereotype threat
A: The threatened feeling that occurs, during the taling of a test, when a person is reminded of the fact that the or she belongs to a group that, according to a culturally prominent stereotype, is expected to perform poorly on the test.

Q: Stevens's power law
A: In psychophysics, S. S. Stevens's idea that the intensity of a sensation is directly proportional to the intensity of the physical stimulus raised by a constant power.

Q: stimulus
A: A well-defined element of the environment that can potentially act on an individual's nervous system and thereby influence the individual's behavior.

Q: strange-situation test
A: A test of an infant's attachment to a particular familiar person, in which the infant's behavior is observed in an unfamiliar room while the familiar person and a stranger move in and out of the room in a preplanned way.

Q: stress-induced analgesia
A: The reduced sensitivity to pain that occurs when one is subjected to highly arousing (stressful) conditions.

Q: Stroop interference effect
A: Named after J. Ridley Stroop, the effect by which a printed color word (such as the word red) interferes with a person's ability to name the color of ink in which the word is printed if the ink color is not the same as the color named by the word.

Q: subject-expectancy effect
A: Any bias in research results that derives from subjects' expectations or beliefs about how they should feel or behave in response to the variables imposed in the study.

Q: subtractive color mixing
A: The mixing of pigments whereby each pigment absorbs a different set of wavelengths of light that would otherwise be reflected to the eye.

Q: superordinate goals
A: The goals shared by two or more groups, which tend to foster cooperation among the groups.

Q: suprachiasmatic nucleus
A: Nucleus (cluster of neurons) in the brain's hypothalamus that controls circadian rhythms of sleep and arousal.

Q: sympathetic division of the autonomic motor system
A: The set of motor neurons that act upon visceral muscles and glands and mediate many of the body's responses to stressful stimulation, preparing the body for possible "flight  or fight".

Q: symptom
A: In clinical psychology or psychiatry, any characteristic of a person's actions, thoughts, or feelings that could be a potential indicator of a mental disorder.

Q: synapse
A: The functional connection through which neural activity in the axon of one neuron influences the action of another neuron, a muscle cell, or a glandular cell.

Q: syndrome
A: In clinical psychology or psychiatry, the entire pattern of symptoms manifested in an individual's behavior and self-statements, which, collectively, may constitute evidence of a mental disorder.

Q: syntax
A: The set of grammatical rules for a given language that specifies how words can be arranged to produce phrases and sentences.

Q: temporal lobe
A: The lobe of the cerebral cortex that lies in front of the occipital lobe and below the parietal and frontal lobes and that contains the auditory area of the brain.

Q: temporal-lobe amnesia
A: The loss in memory abilities that occurs as a result of damage to structures in the limbic system that lie under the temporal lobe of the cerebral cortex.

Q: test
A: In psychology, a data collection method in which stimuli or problems are deliberately presented by the researcher for the subject to respond to.

Q: texture gradient
A: A pictorial cue for perceiving depth in which the gradual change in size and density or textured elements (such as pebbles or blades of grass) indicates depth.

Q: thalamus
A: The brain structure that sits directly atop the brainstemp; it functions as a sensory relay station, connecting incoming sensory tracts to special sensory areas of the cerebral cortex.

Q: theory
A: A belief or set of interrelated beliefs that one has about some aspect of the universe, which is used to explain observed facts and to predict new ones.

Q: three-primaries law
A: The observation that any visible color can be matched by mixing three limited-wavelength lights (called primaries) in differing proportions.

Q: tomotopic organization
A: Refers to the manner by which neural cells in the primary auditory area of the cerebral cortex are organized. Each neuron is maximally responsive to sounds of a particular frequency, and the neurons are systematically arranged such that high-frequency tones activate neurons at one end of this cortical area and low-frequency tones activate neurons at the other end.

Q: top-down control
A: in theories of perception, mental processes that bring preexisting knowledge or expectations about an object or scene bear upon the perception of that object or scene

Q: tract
A: A bundle of neural axons coursing together within the central nervous system; analogous to a nerve in the peripheral nervous system.

Q: trait
A: A hypothetical, relatively stable, inner characteristic that influences the way a person responds to various environmental situations.

Q: trait theories of personality
A: Theories of personality that are based on the idea that people can be described and differentiated in terms of hypothetical underlying personality dimensions, called traits, which can be measured by questionnaires or other quantitative means.

Q: transcranial magnetic stimulation
A: A procedure for temporarily altering the responsiveness of a localized area of the cerebral cortex by creating a magnetic field over that brain area.

Q: transduction
A: The process by which a receptor cell (such as a rod or cone in the eye, or a hair cell in the inner ear) produces an electrical change in response to the energy of a physical stimulus (such as light or sound).

Q: transference
A: The phenomenon by which a patient's unconscious feelings about a significant person in his or her life are experienced consciously as feelings about the therapist.

Q: trichromatic theory of color vision
A: Theory proposed independently by Young and Helmholtz to explain the three-primaries law of color vision; it holds that the human ability to perceive color is mediated by three different types of receptors, each of which is most sensitive to a different range of wavelengths.

Q: ultimate explanation
A: Functional explanations of behavior that state the role that the behavior plays or once played in survival and reproduction, that is, explanations of why the potential for the behavior was favored by natural selection.

Q: unconditioned reflex
A: A reflex that does not depend upon previous conditions in the individual's experience; an unlearned reflex.

Q: unconditioned response
A: A reflexive response that does not depend upon previous conditioning or learning.

Q: unconditioned stimulus
A: A stimulus that elicits a relfexive response without any previous training or conditioning.

Q: unconscious inference
A: With respect to vision, the process by which the brain uses sensory input as clues in order to perceive whole patterns or objects

Q: validity
A: Degree to which a measurement system actually measures the characteristic that it is supposed to measure.  Regarding diagnoses of mental disorders, the degree to which the disorders identified are clinically meaningful; that is, the degree to which the diagnostic labels predict real-world behaviors and treatment outcomes.

Q: variability
A: The degree to which the individual numbers in a set of numbers differ from one another or from their mean.

Q: variable-interval (VI) schedule
A: In operant conditioning, a schedule of reinforcement in which an unpredictable period of time, varying around some average, must elapse between the receipt of one reinforcer and the availability of another.

Q: variable-ratio (VR) schedule
A: In operant conditioning, a schedule of reinforcement in which the response must be produced a certain average number of times before a reinforcer will appear, but the number needed on any given instance varies randomly around that average.

Q: variance
A: A measure of the variability of a set of scores, determined by obtaining the difference (deviation) between each score and the mean, squaring each deviation, and calculating the mean of the squared deviations.

Q: vestigial characteristics
A: Inherited characteristics of anatomy or behavior that are no longer useful to the species but were presumably useful at an earlier time in evolution.

Q: visual agnosia
A: A condition caused by a damage to specific portions of the occipital and temporal lobes of the cortex, in which people cannot make sense of what they see.

Q: visual form agnosia
A: A variety of agnosia in which people can identiy some elements of what they see but cannot perceive an object's shape.

Q: visual object agnosia
A: A variety of agnosia in which people can identify and draw the shapes of objcets bu cannot identify the objects.

Q: visuospatial sketchpad
A: In Baddeley's theory, a component of working memory responsible for holding visual and spatial information.

Q: Weber's law
A: The idea that, within a given sensory modality (such as vision), the difference threshold (amount that the stimulus must be changed in magnitude to be perceived as different) is a constant proportion of the magnitude of the original stimulus.

Q: Wenicke's aphasia
A: A specific syndrome of loss of language ability that occurs due to damage in a particular part of the brain called Wernicke's ara.  Speech in a persos with this disorder typically retains its grammatical structure bu tloses its meaning due to the speaker's failure to provide meaningful content words (nouns, verbs, adjectives and adverbs).

Q: working memory
A: In the modal model, the memory store that is considered to be the main workplace of the mind. Among other things, it is the seat of conscious thought and reasoning.

Q: z score
A: The simplest form of a standardized score; it is the score minus the mean dividied by the standard deviation.

Q: zone of proximal development
A: The range or set of activities that a child can do in collaboration with more competent others but cannot yet do alone.

Q: zygote
A: The single cell that is formed when an egg and sperm cell unite; the first, single-cell form of a newly developing individual.

Q: Colored lights
A: Lights containing limited ranges of wavelengths.

Q: nucleus
A: A cluster of neural cell bodies.

Q: Observer-expectancy effect
A: Any bias in research results that derives from the researcher's desire or expectation that a subject or set of subjects will behave in a certain way.

Q: psychology
A: The science of behavior and the mind.

Q: How might the focus questions (such as this one) in the text's margins be used as a guide to reading this book?
A: One could read and think about each focus question before reading the corresponding paragraph or paragraphs.  Reading with the active intention of answering the question allows one to better focus and understand the text. The focus questions are also helpful for self-testing after one has read an entire chapter.

Q: What was Descartes' version of dualism? How did it help pave the way for a science of psychology?
A: Descartes held a version of dualism that, contrary to most previous versions, did not ascribe all interesting qualities of the human person to the soul, but instead regarded the body as a complex machine that could perform many important functions independently of the soul.  In agreement with Christian doctrine, he claimed that nonhuman animals lacked a soul, but derived from this the conclusion that every human pattern of behavior observed in at least some animal could, in principle, be explained purely mechanistically.  For Descartes, the one essential ability that humans have but animals lack--and the soul's only function--is thought, or the capacity for conscious deliberation and judgment.  Descartes dualism, with its heavy emphasis on a mechanistic conception of the body, helped paved the way for a science of psychology.

Q: Why was Descartes's theory, despite its intuitive appeal, unsuitable for a complete psychology?
A: Descartes's theory has serious problems, regarded both as a philosophy of mind and as a foundation for the science of psychology.  As a philosophy of mind, it fails to explain the interaction between the physical body and the nonphysical soul.  As a foundation for the science of psychology, it excludes from its scope the study of the entire realm of thought, as well as the behaviors guided by thought.

Q: How did Hobbes's materialism help lay the groundwork for a science of psychology?
A: For Hobbes, there exists nothing but matter; mental operations are just processes in the brain.  As a consequence, nothing is beyond the scope of empirical enquiry.

Q: How did the nineteenth-century understanding of the nervous system inspire a theory of behavior called reflexology?
A: François Magendie demonstrated that nerves entering the spinal cord contain two separate pathways: one for carrying messages from skin receptors into the central nervous system, and another one for carrying messages from the central nervous system to operate muscles.  With this understanding of the function of nerves, scientists experimenting with animals began to learn about the neural connections that underlie simple reflexes.  Some of these physiologists, such as I. M. Sechenov, suggested that all human behavior, including voluntary action, occurs through reflexes.

Q: How did discoveries of localization of function in the brain help establish the idea that the mind can be studied scientifically?
A: Such discoveries gave substance to the idea that mental processes have a material basis.

Q: How did the British empiricists explain the origin of complex ideas and thoughts?  What role did the law of association by contiguity play in their philosophy?
A: For Locke and the other British empirical philosophers, all ideas and thoughts originate in experience. These philosophers proposed the law of association by contiguity as the most basic principle of the mind's machinery.  All ideas, even the most complext ones, could in principle be understood as amalgams of elementary ideas that became linked together by association.

Q: What influence has empiricists philosophy had on psychology?
A: The principle of association is still regarded as a fundamental principle of learning and memory in modern psychology.

Q: Why is the ability to learn dependent on inborn knowledge? In Kant's nativist philosophy, what is the distinction between a priori knowledge and a posteriori knowledge?
A: Experience can furnish the mind only if the mind is at least to some degree already furnished with a mechanism that allows it to learn from experience. A priori knowledge--which is already built into the human brain--is thus necessary for the acquisition of a posteriori knowledge--which one gains from exposture to the environemnt.

Q: How did Darwin's theory of natural selection offer a scientific foundation for explaining behavior by describing its functions? How did it provide a basis for understanding the origin of a priori knowledge?
A: Darwin's theory of natural selection showed that the characteristics of an organism could be explained in terms of their functions, that is, their tendency to promote the survival and reproduction of that organism's ancestors.  On this picture, a priori knowledge is also the result of a process of natural selection.

Q: How do neural, genetic, and evolutionary explanations differ from one another? How might each be applied toward an understanding of jealousy?
A: Neural explanations seek to identify how the nervous system produces some experience or behavior.  The research specialty that centers on this level of explanation is referred to as behavioral neuroscience.  Genetic explanations seek to explain psychological differences among individuals in terms of differences in their genes.  The research specialty that centers on this level of explanation is referred to as behavioral genetics.  Finally, evolutionary explanations seek to account for how or why a given trait came about in the course of evolution.  The research specialty that centers on this level of explanation is referred to as evolutionary psychology.

Q: How do learning and cognitive explanations differ?  How might each be applied toward an understanding of jealousy?
A: Learning explanations seek to explain how learning can influence a given behavior.  The psychological specialty that is most directly and exclusively concerned with explaining behavior in terms of learning is called learning psychology.  Cognitive explanations seek to explain action or experience by relating it to the cognitions (items of mental information) that underlie that action or experience.  The specialty focusing on this level of analysis is called cognitive psychology.

Q: How do social and cultural explanations differ? How might each be applied toward an understanding of jealousy?
A: One way to explain experience and behavior is to identify how they are influenced by other people or by one's beliefs about other people.  The specialty focusing on this level of explanation is called social psychology.   Another way to explain experience and behavior is by relating them to the culture that the person grew up in.  The specialty that explains mental experiences and behavior in terms of the culture in which the person developed is called cultural psychology.

Q: What constitutes a developmental explanation? How can such an explanation be applied toward an understanding of jealousy?
A: Some aspects of a person's behavior can be explained by his or her age.  The psychological specialty that documents and describes the typical age differences that occur in the ways that people feel, think, and act is called developmental psychology.

Q: What are some research specialties in psychology that are not defined primarily by the level of analysis employed?
A: Many psychological research specialties correspond to different levels of analysis.  Examples of these specialties include behavioral neuroscience, behavioral genetics, evolutionary psychology, psychology of learning, cognitive psychology, social psychology, cultural psychology and developmental psychology.  Other specialties, however, are defined more in terms of topics studied than levels of analysis.  Examples include sensory psychology, perceptual psychology, the psychology of motivation and the psychology of emotion, as well as personality psychology, abnormal psychology and clinical psychology.

Q: How does psychology link the three main divisions of academic studies?
A: According to the "psychocentric" theory of the university, psychology is the one discipline that ties together disciplines in the major areas.  On the natural science end, psychology is tied most directly to biology by way of behavioral neuroscience, behavioral genetics, and evolutionary psychology.  On the social science end, it is tied most directly to sociology and anthropology by way of social and cultural psychology.  In addition to bridging the natural and social sciences, psychology ties the whole spectrum of science to the humanities its interest in how people produce and understand languages, philosophies, art, and music.

Q: How did Clever Hans give the appearance of answering questions, and how did Oskar Pfungst unveil Hans's methods?
A: Clever Hans was able to communicate by spelling words using foot taps and by using head movements to say 'yes' and 'no'.  Oskar Pfungst unveiled that Hans's didn't actually know the answers to the questions we was asked, but instead was merely respondign to subtle and involuntary signals from audience members.  The proof was that Hans was unable to answer a question when his eyes were covered or no member in the audience knew the answer.

Q: How are facts, theories, and hypotheses related to one another in scientific research?
A: Facts lead to theories, which seek to explain the facts and predict the future, and theories lead to hypotheses, which are tested with eperiments or other research studies, which lead to new facts, new theories, new hypotheses, and so on.

Q: How does the Clever Hans study illustrate (1) the value of skepticism, (2) the value of controlled experimentation, and (3) the need for researchers to avoid communicating their expectations to subjects?
A: (1) In general, people want to believe, and this is as true of  the general population as of the community of professional researchers.  It is therefore very important to cultivate a skeptical attitude that counteracts this natural human tendency.  (2) Pfungst could discover the truth about Clever Hans by by identifying the conditions under which the horse could and could not respond correctly to questions.  Carful observation under controlled conditions is a hallmark of the scientific method. (3) Observer may unintentionally communicate their expectations to the subjects, and as a consequence the subjects may behave as expected, even if the theory that generated those expectations was false.  To adequately test a hypothesis, therefore, researchers must take active measures to prevent communicating their expectations.

Q: What are the three dimensions along which research strategies in psychology may be categorized?
A: A useful way to categorize the various research strategies used by psychologists is to think of them as varying along the following three dimensions:
1. The research design, of which there are three basic types--experiments, correlational studies, and descriptive studies.
2. The setting in which the study is conducted, of which there are two basic types--field and laboratory.
3. the data-collection method, of which there are two basic types--self-report and observation.

Q: How can an experiment prove the existence of a cause-effect relation between two variables?
A: In an experiment, the researcher systematically manipulates one or more independent variables, while keeping all other variables constant.  Since all other variables are kept constant, and only the independent variables are changed, it is reasonable to infer that any change observed in the dependent variable is caused by changes in the independent variables.

Q: What were the independent and dependent variables in Pfungst's experiment with Clever Hans?
A: Pfungst tested Hans sometimes with blinders and sometimes without.  In that experiment the independent variable was the presence or absence of blinders, and the dependent variable wasa the percentage of questios the horse answered correctly.  This experiment is a within-subject experiment, because the different conditions of the independent variable were applied to the same subject.

Q: What were the independent and dependent variables in DiMascio's experiment on treatments for depression?  Why were the subjects randomly assigned to the different treatments rather than allowed to choose their own treatment?
A: In Alberto DiMascio's classic experiment in clinical psychology, the independent variable was the kind of treatment given (psycotherapy, drug therapy, or both), and the dependent variable was the degree of depression after 16 weeks of treatment.  This is a between-groups experiment, because the manipulations of the independent variable were applied to different groups of subjects.  The subjects were randomly assigned to the different treatments because otherwise the results could be attributed to a property causing subjects to choose one group over another, rather than to the independent variable.  If  random assignment is used instead, the effects not due to the independent variable could only be due to chance, which can be reduced to arbitrarily low levels by increasing the sample size sufficiently.

Q: What are the differences between a correlational study and an experiment, in procedure and in types of conclusions that can be drawn?
A: Unlike experiments, correlational studies do not manipulate any variable, but instead try to measure or observe existing variables and find relationships between them.  Such studies cannot directly establish causal relationships.

Q: How does an analysis of Diana Baumrind's classic study of parental disciplinary styles illustrate the difficulty of trying to infer cause and effect from correlation?
A: Baumrind's study is compatible with each of these causal hypotheses:
1. Differences in children's behavior may cause differences in parents' disciplinary style, rather than the other way around.
2. The causal relationship may go in both directions, with parents and children influencing each other's behavior.
3. A third variable, not measured in Baumrind's study, may influence both parental style and children's behavior in such a way as to cause the observed correlation.

Q: How do descriptive studies differ, in method and purpose, from experiments and from correlational studies?
A: Descriptive studies seek to describe the behavior of an individual or set of individuals without assessing relationships between different variables.

Q: What are the relative advantages and disadvantages of laboratory studies and field studies?
A: Laboratory studies and field studies offer opposite sets of advantages and disadvantages.  The laboratory allows the researcher to collect data under more uniform, controlled conditions than are possible in the field.  However, the strangeness or artificiality of the laboratory may induce behaviors that distort those that the researcher wants to study.  For this reason, when laboratory and field studies reach the same conclusion, researchers can be reasonably confident that the conclusions are true.

Q: How do self-report methods, naturalistic observations, and tests differ from one another?  What are some advantages and disadvantages of each?
A: Questionnaires and interviews (the two types of self-report methods) can provide information that researchers would not be able to obtain by watching subjects directly.  However, the validity of such data is limited by the subjects' ability to observe and remember their own behaviors or mental states and by their willingness to report those observations sincerely.  Naturalistic observations (a type of observational method) allow researchers to learn firsthand about their subjects' natural behaviors, but the practicality of such methods is limited by the great amount of time they take, the difficulty of observing ongoing behavior without interfering with it, and the difficulty of coding results in a form that can be used for statistical analysis.  Tests (another type of observational method) are convenient and easily scored but are by nature artificial, and their relevance to everyday behavior is not always clear.

Q: How do the mean, median, and standard deviation help describe a set of numbers?
A: The mean and median describe the central tendency of a set of numbers; the standard deviation describes variability of the numbers.

Q: How does a correlation coefficient describe the direction and strength of a correlation?  How can correlations be depicted in scatter plots?
A: A positive correlation coefficient indicates that an increase in one variable coincides with a tendency for the other variable to increase; a negative correlation coefficient indicates that an increase in one variable coincides with a tendency for the other variable to decrease.  The absolute value of the correlation coefficient indicates the strength of the corration; to the degree that a correlation is strong (close to +1.00 or -1.00), one can predict the value of one variable by knowing the other.

Q: Why is it necessary to perform inferential statistics before drawing conclusions from the data in a research study?
A: Any set of data collected in a research study contains some degree of variability that can be attributed to chance, i.e., random effects caused by uncontrollable variables.  This is the main reason why inferential statistics are necessary.

Q: What does it mean to say that a result from a research study is statistically significant at the 5 percent level?
A: In the casae of comparing two means in an experiment, the level of statistical significance (p) is the probability that a difference as large as or larger than that observed would occur if the independent variable had no real effect on the scores.In the case of a correlational study, p is the probability that a correlation coefficient as large as or larger than that observed would occur by chance if, in the larger population, the two variables were uncorrelated.

Q: How is statistical significance affected by the size of the effect, the number of subjects or observations, and the variability of the scores within each group?
A: Other things equal, a large effect is more significant than a small one.  For example, the larger the difference found between the mean scores for one group compared to another in an experiment, the more likely it is that the effect is statistically significant.  Other things equal, the more subjects or observations included in a research study, the more significant are the results.  And other things equal, the less the variability within each group, the more significant the results.

Q: What is the difference between error and bias, and why is bias the more serious problem?
A: Error is random variability in results.  Because error is random, its consequences tend to disappear when averages are calculated, especially when the data set is large; and because error can be quantified precisely, by calculating the standard deviation, researchers can take it into account in their inferential statistics.  By contrast, bias does not tend to disappear when averages are computed and sample sizes increased, nor can it be measured with precision.

Q: What are the main types of bias?
A: Sampling bias, measurement bias, and expectancy bias.

Q: How can a nonrepresentative selection of research subjects introduce bias into (a) an experiment and (b) a descriptive study?
A: In experiments, sampling bias is introduced by not assigning subjects randomly to different groups.  In descriptive studies, sampling bias is introduced by polling subjects who are not representative of the larger population, as the Literary Digest's when surveying voters in the 1936 US election.

Q: What is the difference between the reliability and the validity of a measurement procedure? How can lack of validity contribute to bias?
A: A measure is reliable to the degree that it yields similar results each time it is used with a particular subject under a particular set of conditions.  A measure is valid if it explains or predicts what it is inteded to measure or predict.  If common sense tells us that a measurement procedure assesses the intended characteristics, we say the procedure has face validity.

Q: How can the validity of a measurement procedure be assessed?
A: The validity of a measurement is best assessed by correlating it with another, more direct index of the same characteristic.  This more direct index is called the criterion, and the validity is called criterion validity.

Q: How can the supposed phenomenon of facilitated communication by people with autism be explained as an observer-expectancy effect?
A: In a typical experiment, pairs consisting of a facilitator and an autistic person were tested under two conditions.  In one condition, the item of information that the autistic person was asked to communicate was also shown to the facilitator, and in the other condition it was not.  The inevitable result was that many correct responses were typed in the first condition but not in the second.

Q: What are two ways by which an observer's expectations can bias results in a typical experiment?  How does blind observation prevent such bias?
A: Observers' expectations can both influence subjects' behavior and observers' perceptions or judgments concerning that behavior.  By blinding the observer to those aspects of the study that could create expectations, both biases are avoided.

Q: How can subjects' expectancies bias the results of an experiment?  How does a double-blind procedure control both subjects' and observers' expectancies?
A: If a subject knows that he is receiving a certain type of treatment, he or she migh form expectations that could potentially affect the treatment's outcome.  Double-blind procedures keep observers and subjects uninformed about the treatment that is being administered, and as a consequence the corresponding observer- and subject-expectancy biases are avoided.

Q: What are the ethical concerns pertaining to privacy, discomfort, deception, and animal welfare in psychological research?  How do researchers strive to minimize problems related to these concerns?
A: 1. Privacy: adequate safeguards must be taken to protect subjects' privacy.
2. Discomfort or harm: studies involving some risk of discomfor or harm to subjects can only be conducted when the research question could not be answered by a study involving less risk; when the risk is minimal and outweighed by the human benefits of the study; and when subjects are advised that they are free to quit at any time.
3. Deception: there is disagreement over the extent to which depcetion is acceptable.
4. Animals: most researchers agree that some procedures that would be unethical to use with humans can be used ethically with other animal species.

Q: How can genes affect behavioral traits through their role in protein synthesis?
A: Genes affet the body's development only through their influence on the production of protein molecules.  Some genes, called coding genes, code for unique protein molecules, whereas other genes, called regulatory genes, work through various biological means to help activate or suppress specific coding genes.

Q: What does it mean to say that genes can influence behavioral traits only through interaction with the environment?  How, in general, are genes involved in long-term behavioral changes that derive from experience?
A: Genes build proteins, which form or alter the body's physiological systems (including brain systems), which, in turn, produce behavior.  Each step in this process involves interaction with the environment (which refers to every aspect of an individual and his or her surroundings except the genes themselves).  Aspects of the internal environment control gene activation, and aspects of both the internal and the external environments act on physiological systems to control behavior.  Behavior, in turn, can affect gene activation through direct and indirect effecs on the internal environment.

Q: How can the same genotype produce various phenotypes?
A: Two individuals with the same genotype can be quite different in phenotype as a result of differences in their environments.

Q: How does meiosis produce egg or sperm cells that are all genetically different from one another?
A: When cells divide to produce egg or sperm cells, they do so by a process called meiosis.  During meiosis, each chromosome replicates itself once, but then the cell divides twice.  Before the first cell division, the chromosomes of each pair line up next to one another and exchange genetic material in a random manner.  As a consequence of this and the subsequent cell division, each egg or sperm cell produced is genetically different from any other egg or sperm cell, and contains only half of the full number of chromosomes.

Q: What is the advantage of producing genetically diverse offspring?
A: In an environment that is constantly changing, genes have a better chance of surviving if they are reshuffled at each generation.  By producing diverse offspring, parents are reducing the chance that all their descendants will die as a result of some unforeseen change.

Q: What is the difference between a dominant and a recessive gene (or allele)?
A: A dominant gene (or allele) is one that will produce its observable effects in either the homozygous or the heterogyzous condition; a recessive gene (or allele) is one that will produce its effects in the homozygous condition only.

Q: Why do three-fourths of the offspring of two heterozygous parents show the dominant trait and one-fourth show the recessive trait?
A: When two individuals that are heterozygous at a given locus are crossed, four possible gene combinations occur in the offspring.  Of these four, three will contain at least  one dominant allele, and as a consequece three fourths of the offspring will will exhibit the dominant trait.  The remaining combination will contain both recessive alleles, and as a consequence one fourth of the offpsring will exhibit the recessive trait.

Q: How did Scott and Fuller show that the difference in fearfulness between cocker spaniels and basenji hounds is controled by a single gene locus, with the "fear" allele dominant over the "non-fear" allele?
A: The researchers first mated cocker spaniels with basenjis, and observed that all puppies exhibited typical fearful behavior.  They then mated these hybrids with each other, and observed a 3:1 raio of fearful versus fearlessness, in line with prediction.  They also mated hybrids with purebred cockers and the result was that about half the offspring were fearful and half were fearless, again confirming the hypothesis that this trait was controlled by a single gene locus.

Q: Why would it be a mistake to conclude, from Scott and Fuller's work, that fear in dogs is caused just by one gene or that it is caused just by genes and not the environment?
A: The phenomenon was observed in only a couple of dog breeds; it is unreasonable to assume that a complex emotion such as fear will be controlled by a single gene in all dog breeds.  Moreover, throughout the experiment the environement was kept constant, so the study provides no evidence about the relative contribution of genetic and environmental influences.

Q: How did the pattern of inheritance of a disorder in language ability, in a particular family, show that the disorder is caused by a single dominant gene?  Also, what other general ideas about genetic influences are  illustrated by this example?
A: In the example, when neither parent had the speicifc language impairment, no child had it, and when one parent had it, about half of the offspring had it.  This is just what one would expect if the impariment results from a single dominant gene.  More generally, the example illustrates that
* Genes can influence behavior by influencing the development of particular areas of the brain.
* A single gene can have multiple effects.
* Some genes exert their effects by activating sets of other genes, thereby controlling the production of several or many different protein molecules.
* The evolution of human beings (and of other species) involves alterations in anatomy and behavior that derive from alterations in genes.

Q: How does the distribution of scores for a polygenic trait differ from that usually obtained for a single-gene trait?
A: Characteristics that derive from variation at a single gene locus are typically categorical in nature.  Most measurable anatomical and behavioral differences among individuals, however, are differences in degree, not in type; they are continuous.  Most often, the set of scores obtained on such measures approximate a normal distribution. Characteristics that vary in a continuous way are generally affected by many genes and are therefore called polygenic characteristics.

Q: How are the characteristics of animals shaped through selective breeding?
A: The members of each generation that best approximated the desired type were mated to produce the next generation, resulting in a continuous genetic molding tward the varieties we see today.

Q: How did Tryon produce "maze bright" and "maze dull" strains of rats?  How did he show that the difference was the result of genes, not rearing?
A: Tryon tested a group of rats for their ability to learn a particular maze, put the rats who had made the fewest and most errors in separate groups, and mated the members within each group, repeating this process over many generations.  The groups become progressively more distinct, until there was hardly any overlap between them.  To control for the possibility that the offspring were somehow learning to be bright or dull from their mothers, Tryon also cross-fostered the rats so that some of the offspring from each strain were raised by mothers in the other strain.

Q: Why is the strain difference produced by Tryon not properly characterized in terms of "brightness" or "dullness"?
A: Researchers tested Tryon's "dull" rats at other learning tasks and found that they were no worse, and sometimes even better, than the "bright" rats.  The differences between the two groups of rats are therefore not differences in general cognitive ability.

Q: What insight led Darwin to his theory of evolution?  How is natural selection similar to and different from artificial selection?
A: The idea that plants and animals can be modified by selective breeding was understood long before Darwin was born.  Darwin's true, original insight was that breeding in nature is also selective and can also produce changes in living things over generations.

Q: What was Darwin's essential point?
A: Individuals of a species vary in the number of offspring they produce.  Some produce none, because they die early or fail to mate; others produce many.  Any inherited trait that increases the number of offspring that an individual produces is automatically "selected for," as the trait is passed on to those offpsring.  Conversely, any inherited trait that decreases the number of one's offpsring is automatically 'selected against," appearing in fewer members of the next generation.  Thus, as long as inheritable differences exist among individuals in an interbreeding population, and as long as some of those differences affect survival and reproduction, evolution will occur.

Q: How are genes involved in evolution?  What are the sources of genetic diversity on which natural selection operates?
A: Genes are the units of heredity, and evolution works by producing changes, from generation to generation, in the frequencies of particular genes in an interbreeding population.  Genes that improve an individual's ability to survive and reproduce in the existing environment increase from generation to generation, and genes that impede this ability decrease from generation to generation.

Q: How does change in the environment affect the direction and speed of evolution?  How did a study of finches illustrate the role of environmental change in evolution?
A: Evolution can occur rapidly, slowly, or almost not at all, depending on the rate and nature of environmental change and on the degreee to which genetic variability already exists in a population.  In the 1970s, a severe drought lasting many years caused most of the finches in one of the Galápagos Islands to die because the plants that produce the seeds they eat failed to grow.  The birds that survived and produced offspring were those thathappened to have thicker, more powerful beaks.

Q: What are three mistaken beliefs about evolution, all related to the misconception that foresight is involved?
A: 1. The belief that evolution could produce changes for some future purpose, even though they are useless or harmful at the time that the change occurs.  This belief is false because evolution is a blind process which has no foresight.
2. The belief that present-day organisms can be ranked according to the distance they have moved along a set evolutionary route, toward some planned end.  This belief is false, because evolution has no set route or planned end.
3. The belief that natural selection is a moral force, that its operation and its products are in some sense right or good.  This belief is false becausenature is neither good nor bad, moral nor immoral.

Q: How does an understanding of evolution provide a basis for functionalism in psychology?
A: The mechanisms underlying behavior are products of natural selection, and as such they came about because they promoted survival and reproduction.  This evolutionary origin of the mechanisms for behavior provides the basis for functionalism in psychology, which attempts to explain behavior in terms of what it accomplishes for the behaving individual.

Q: How are ultimate explanations of behavior different from, but complementary to, proximate explanations?
A: Ultimate explanations are functional explanations at the evolutionary level.  Proximate explanations are explanations that deal not with function but with mechanism; they are statements of the immediate conditions, both inside and outside the animal, that bring on the behavior.

Q: What are four reasons for the existence of traits or behaviors that do not serve survival and reproduction functions?
A: 1. Some traits are vestigial. Some traits that evolved to serve the needs of our ancestors remain despite no longer being functional today.  An example is the grasp reflex by which newborn infants close their fingers tightly around objects in their hands.  The concept of vestigial traits becomes especially relevant to psychologists when applied to our inherited drives, or motives.  An example is our appetite for sugar.
2. Some traits are side effects of natural selection for other traits.  Useless changes can come about in evolution as by-products of natural selection for other, useful changes. An example is the belly button, which serves no function but is simply a remnant of the umbilical cord.
3. Some traits result simply from chance.  Some inheirtable characteristics that result from just one or two mutations are inconsequential for survival and reproduction.  A possible example is variation in nose shapes: maybe the small group of people who migrated to a specific part of the world, and who were the ancestors of a particular racial group, just happened to carry along genes for a nose shapethat was different from the average for the group they left (a process known as genetic drift).
4. Evolved mechanis cannot deal effectively with every situation.  Our traits evolved because they promoted survival and reproduction better than preexisting traits on balance.  It doesn't follow, however, that such traits promote survival and reproduction always.  An example is guilt, which serves the ultimate function of helping us to preserve our relationships with people whose help we need for survival and reproduction.  It is clear, however, that some instances of guilt do not adequately serve this function.

Q: What evidence supports the idea that many human emotional expressions are examples of species-typical behavior?
A: There are six basic emotional expressions in people--surprise, fear, disgust, anger, happiness, and sadness--which have been observed in every culture and which members of every culture recognize as such in other cultures.  Such expressions are also observed in congenitally blind people, who clearly could not have learned them from observing their environment.