N.C.C. - National Certified Counselor
naloxone A drug that blocks the pain alleviation ascribed to endorphins and inhibits the effect of morphine and similar opiates by binding to opiate receptors in the brain.
nativism The view that some important aspects of perception and of other cognitive processes are innate.
natural selection the evolutionary process by which nature selects traits that best enable organisms to survive and reproduce in particular environmental niches.
natural selection The explanatory principle by which Darwin accounted for biological evolution. It refers to the greater number of offspring reaching sexual maturity shown by individual organisms possessing hereditary attributes that are advantageous in a given environment. Continued natural selection over many generations can result in wholesale changes in bodily form and behavior that may result in the development of new species.
naturalist fallacy the error of defining what is good in terms of what is observable. For example: What's typical is normal; what's normal is good.
nature-versus-nurture debate: arguments concerning the relative degree to which heredity and learning affect functioning.
Need for cognition An individual preference for and tendency to engage in effortful cognitive activities.
need to belong a motivation to bond with others in relationships that provide ongoing, positive interactions.
negative afterimage In color vision, the persistence of an image that possesses the hue complementary to that of the stimulus (e.g., seeing a yellow afterimage after staring at a blue lamp), resulting from the operation of opponent processes.
negative cognitive schema For Aaron Beck, the core cognitive component of depression, consisting of an individual’s automatic negative interpretations concerning himself, his future, and the world. See alsoexplanatory style.
negative feedbackSeefeedback system.
Negative state relief model A theory suggesting that for those in a bad mood, helping others may be a way to lift their own spirits if the perceived benefits for helping are high and the costs are low.
negative symptoms of schizophrenia Symptoms that involve deficits in normal functioning, such as apathy, impoverished speech, and emotional blunting. See alsopositive symptoms of schizophrenia.
Negativity bias The tendency for negative traits to be weighted more heavily than positive traits in impression formation.
neglect syndrome The result of certain lesions of the right parietal lobe that leave a patient inattentive to stimuli to her left (e.g., not eating food on the left side of the plate) and result in her ignoring the left side of her body (e.g., putting makeup on only the right side of her face). See alsoGerstmann syndrome.
neocortex The outermost, convoluted layer of the forebrain, often referred to merely as the cortex.
neo-Freudians A group of theorists who accept the psychoanalytic conception of unconscious conflicts but who differ with Freud in ways that can include (1) describing these conflicts in social terms rather than in terms of bodily pleasures or frustrations, (2) maintaining that many of these conflicts arise from specific cultural conditions instead of being biologically preordained.
neonatal period: the first 4 weeks of life outside the womb.
neophobia Literally "fear of the new," the term is used in the study of food selection to refer to an animal’s tendency to refuse unfamiliar foods.
nerve growth factors Neurochemicals that promote the sprouting of new neuronal connections.
nerve impulseSeeaction potential.
network model Theories of cognitive organization, especially of semantic memory, which hold that items of information are represented by a system of nodes linked through associative connections. See alsoconnectionist model, distributed representations, local representations, node.
neural networks Assemblies of associative elements that use parallel distributed processing and are hypothesized to function like neuronal circuits. See alsoparallel distributed processing.
neural plasticity The capacity for neurons to alter their functioning as a result of experience.
neural plate A small thickening, running the length of the embryo, from which the neural tube and, eventually, the nervous system, develop.
neural tube The tubular structure, formed by the fusion of the edges of the neural plate, from which the central nervous system (forebrain, midbrain, hindbrain, and spinal cord) develops.
neurodevelopmental disorder A disorder that stems from early brain abnormalities. Many researchers believe that schizophrenia is one such disorder and may originate in abnormal fetal brain development.
neuroimaging instruments Electronic devices that permit noninvasive study and depiction of brain structure or function. (See alsoCT scan, MRI scan, fMRI scan, and PET scan).
neurons: the structural and functional unit of the nervous system, consisting of the nerve cell body and all its processes, including an axon and one or more dendrites.
neuropeptide Y (NPY) A chemical found widely in the brain and periphery. In the brain, it acts as a neurotransmitter; when administered at sites in and near the hypothalamus, it is a potent elicitor of eating.
neuropsychological assessment A specialized kind of psychological testing used to pinpoint the pattern of cognitive strengths and impairments that occurs with learning disabilities, aging, brain injuries, or diseases.
neurosis A broad term once used for mental disorders whose primary symptoms are anxiety or what seem to be defenses against anxiety. Since the adoption of DSM-III, the term has been dropped as a broad diagnostic label, and what were once considered the various subcategories of neurosis (e.g., phobia, anxiety, conversion and dissociative disorders) are now classified as separate disorders.
neuroticism A trait dimension that refers to emotional instability and maladjustment.
neurotoxin Any chemical poisonous to neurons.
neurotransmitters Chemicals liberated at the terminals of an axon that cross the synaptic gap and have excitatory or inhibitory effects on the postsynaptic neuron (e.g., norepinephrine, serotonin, GABA).
nocturnal emissions: the release of semen during sleep (wet dreams).
node A point in a network at which a number of connections converge.
nodes of Ranvier The gaps occurring between the glial-cell wrappers that form the myelin sheath surrounding many kinds of axons. The nodes are crucial to the rapidity at which neural impulses travel along myelinated axons.
nominal scale A scale in which responses are ordered only into different categories. See alsocategorical scale, interval scale, ordinal scale, and ratio scale.
nondirective techniques A set of psychotherapy techniques devised by Carl Rogers. As far as possible, the counselor refrains from offering advice or interpretation but only tries to clarify the patient’s own feelings by echoing or restating what he says.
nonfluent aphasia Speech disorder in which the main difficulty is in speech production, often involving damage to Broca’s area in the frontal lobe.
nonsense syllable Two consonants with a vowel between that do not form a word. Used to study associations between relatively meaningless items.
Nonverbal behavior Communicating feelings and intentions without words.
nonviable fetus: a fetus that is unable to live on its own.
non-zero-sum games games in which outcomes need not sum to zero. With cooperation, both can win; with competition, both can lose. (Also called mixed-motive situations.)
norepinephrine (NE) The neurotransmitter found in the nerves of the sympathetic branch of the ANS. It is also one of the neurotransmitters involved in various arousal systems in the brain.
Norm An expected standard of behavior and belief established and enforced by a group.
Norm of social justice A social norm stating that we should help only when we believe that others deserve our assistance.
Norm of social responsibility A social norm stating that we should help when others are in need and dependent on us.
normal curve A symmetrical, bell-shaped curve that describes the probability of obtaining various combinations of chance events. It depicts the normal distribution, the frequency distribution of many physical and psychological attributes of humans and animals.
normal distribution A frequency distribution whose graphic representation has a symmetric, bell-shaped form — the normal curve. Its characteristics are often referred to when investigators test statistical hypotheses and make inferences about the population from a given sample.
normative influence conformity based on a person's desire to fulfill others' expectations, often to gain acceptance.
Normative social influence Conformity, compliance, or obedience due to a desire to gain rewards or avoid punishments (outcome dependence).
norms rules for accepted and expected behavior. Norms prescribe "proper" behavior. (In a different sense of the word, norms also describe what most others do-what is normal.) In intelligence testing, the scores taken from a large sample of the population against which an individual’s test scores are evaluated.
Nosology Nosology deals with the classification or listing of diseases. The most relevant nosological scheme relevant to psychotherapy is the Diagnostic and Statistical Manual of the American Psychiatric Association, the DSM.
novice phase: a phase of early adulthood, ranging from ages 17 to 33.
nucleus accumbens A dopamine-rich area in the forebrain that is critical in the physiology of reward.
null hypothesis The hypothesis that an obtained difference is merely a chance fluctuation from a population in which the true mean difference is zero. See alsoalternative hypothesis.
Obedience The performance of an action in response to a direct order.
obesity A condition of marked overweight in animals and humans produced by a large variety of factors including genetic predisposition ("thrifty" genes), metabolic factors (oversecretion of insulin), and behavioral conditions (overeating, insufficient exercise). Being 20 percent or more above one's ideal weight.
object permanence The conviction that an object remains perceptually constant over time and exists even when it is out of sight. According to Piaget, this does not develop until infants are eight months old or more.
object permanence: the knowledge that out-of-sight objects still exist, learned by infants at around 9 months.
objective personality testSeestructured personality test.
object-relations theory: Melanie Klein's theory that the inner core of personality stems from the early relationship with the mother.
observational learning A mechanism of socialization whereby a child observes another person who serves as a model and then proceeds to imitate what that model does. Learning by watching the actions of others and noting that subsequent rewards they receive. The process by which learning is achieved through observing and imitating others.
observational research: research based on the observation of subjects in laboratory or natural settings rather than on experimentation or interviews.
observational study A study in which the investigator does not manipulate any of the variables but simply observes their relationship as they occur naturally.
obsessive-compulsive disorder A disorder whose symptoms are obsessions (persistent and irrational thoughts or wishes) and compulsions (uncontrollable, repetitive acts), which seem to be defenses against anxiety. A member of a diagnostic category called anxiety disorders, which also includes generalized anxiety disorder and phobias.
occipital lobe The rearmost lobe in each cerebral hemisphere, which includes the primary visual projection area.
occlusion The partial concealment of one object by another object in front of it.
Oedipus complex In psychoanalytic theory, a general term for the cluster of impulses and conflicts that occurs during the phallic phase, at around age five. In boys, a fantasized form of intense, possessive sexual love is directed at the mother, which is soon followed by hatred for and fear of the father. As the fear mounts, the sexual feelings are pushed underground and the boy identifies with the father. An equivalent process in girls is called the Electra complex.
Oedipus conflict: the unconscious tendency of a child to be attached to the parent of the opposite sex and hostile toward the other parent. Its persistence in adult life results in neurotic disorders. Originally restricted to a son's attachment.
Old-fashioned racism Blatantly negative stereotypes based upon White racial superiority, coupled with open opposition to racial equality.
olfaction The sense of smell.
olfactory epithelium The small area at the top of the nasal cavity that contains receptors reactive to airborne chemicals.
one-trial learning In classical conditioning, the establishment of a conditioned response (CR) after only one pairing of conditioned stimulus (CS) and unconditioned stimulus (US).
only child: a child without siblings.
operant conditioning: a form of conditioning in which the desired response, when it occurs, is reinforced by a stimulus. See instrumental conditioning .
operant In Skinner’s system, an instrumental response. See alsoinstrumental conditioning.
opponent-process theory of color vision A theory of color vision that proposes three pairs of color antagonists: red-green, blue-yellow, and white-black. Excitation of one member of a pair automatically inhibits the other member.
opponent-process theory of motivation A theory that asserts that the nervous system tends to counteract any deviation from the neutral point on the pain-pleasure dimension. If the original stimulus is maintained, there is an attenuation of the emotional state one is in; if it is withdrawn, the opponent process reveals itself, and the emotional state swings sharply in the opposite direction.
optic flow The phenomenon wherein an object’s retinal image enlarges as we approach the object and shrinks as we retreat from it. It is used as a depth cue by the visual system.
optic nerve The bundle of fibers that proceeds from each eyeball to the brain, made up of axons whose cell bodies are retinal ganglion cells.
Optimistic explanatory style A habitual tendency to attribute negative events to external, unstable, and specific causes, and positive events to internal, stable, and global causes.
oral character According to Freud, a personality type based on a fixation at the oral stage of development and whose manifestations can include passive dependency or "biting" hostility. See alsooral stage.
oral stage In psychoanalytic theory, the earliest stage of psychosexual development during which the primary source of bodily pleasure is stimulation of the mouth and lips, as in sucking at the breast. The earliest stage of psychosexual development in which interest centers around sucking, feeding, and biting.
ordinal scale A scale in which responses are rank-ordered by relative magnitude but in which the intervals between successive ranks are not necessarily equal. See alsocategorical scale, interval scale, nominal scale, and ratio scale.
orexins Hormones synthesized in the lateral hypothalamus that are potent elicitors of eating.
organic brain syndrome: mental deterioration, also known as dementia. Mental disorders that are reliably associated with definitive brain damage (e.g., Alzheimer’s disease).
oscilloscope An electronic monitoring device that uses a cathode ray tube (CRT) to display electrical signals such as electrocardiograph signals or action potentials.
osmoreceptors Receptors that help to control water intake by responding to the concentrations of bodily fluids. See alsovolume receptors.
ossicles The three small bones in the ear that transmit vibrations from the eardrum to the oval window.
Outcome dependence Dependence upon others for positive outcomes or rewards (also know as normative dependence).
outcome measures In psychopathology, variables (e.g., mood ratings, work absenteeism) assessed to indicate whether a particular treatment was effective or cost-effective.
outer ear The portion of the structures of the ear that includes the earflap, the auditory canal, and the outer surface of the eardrum.
outgroup "them"-a group that people perceive as distinctively different from or apart from their ingroup. A social group with which one does not identify or to which one does not belong. Any group with which a person does not share membership.
outgroup homogeneity effect A phenomenon related to stereotyping in which a member of a group (the in-group) tends to view members of another group (the out-group) as more alike (less varied) than are members of his or her own group. Perception of outgroup members as being more similar to one another than are members of one's ingroup.
oval window The membrane separating the middle ear from the inner ear.
overconfidence phenomenon the tendency to be more confident than correct to overestimate the accuracy of one's beliefs.
overjustification effect the result of bribing people to do what they already like doing; they may then see their action as externally controlled rather than intrinsically appealing.
overregularization errors Errors in speech production in which an irregular noun or verb is treated as though it were regular (e.g., foots for feet or goed for went). These errors are often made by young children, which suggests that children discover the rules of language and do not simply imitate what they hear.
ovulate: to produce and discharge ova from the ovary.
ovum An egg cell manufactured in an ovary and contributed by the female as part of sexual reproduction.
ovum: a mature female germ cell which, only after fertilization, develops into a zygote and then a fetus.
own-race bias the tendency for people to more accurately recognize faces of their own race.
pain The aversive sensation that usually accompanies tissue damage and alerts the organism to engage in protective or reparative behavior.
paired-associate method A procedure in which research participants learn to provide particular response terms to various stimulus items.
panic attack A sudden episode consisting of terrifying bodily symptoms such as labored breathing, choking, dizziness, tingling in the hands and feet, sweating, trembling, heart palpitations, and chest pain. Panic attacks occur in a number of mental disorders and are common in phobias, panic disorder, and post-traumatic stress disorder (PTSD).
panic disorder An anxiety disorder characterized by repeated or disabling panic attacks. See alsoanxiety disorders, panic attack.
parallel distributed processing (PDP) Models of cognitive processing in which the relevant symbolic representations do not correspond to any one unit of the network but to the state of the network as a whole.
parallel search The simultaneous comparison of a target stimulus to several items in memory. See alsoserial search.
parameter One of the ways that languages can depart from a hypothesized universal linguistic structure (e.g., omission of the subject in certain sentences).
paranoia: a mental disorder characterized by systematized delusions, as of grandeur or, especially, persecution; often, except in a schizophrenic state, occurring within an otherwise relatively intact personality.
paranoid schizophrenia A subcategory of schizophrenia. Its dominant symptom is a set of delusions that are often elaborately systematized, usually of grandeur or persecution.
paraphrase The relation between two sentences whose meanings (underlying structures) are the same but whose surface structures differ (e.g., "The boy hit the ball"/"The ball was hit by the boy").
parasympathetic system A division of the autonomic nervous system that serves vegetative functions and conserves bodily energies (e.g., slowing heart rate). Its action is often antagonistic to that of the sympathetic system.
parental control: the degree to which parents are restrictive in their use of parenting techniques.
parental warmth: the degree to which parents are loving, affectionate, and approving in their use of parenting techniques.
parietal lobe The lobe in each cerebral hemisphere that lies between the occipital and frontal lobes, and that includes the primary sensory projection area.
Parkinson’s disease A degenerative neurological disorder characterized by various motor difficulties that include tremor, muscular rigidity, and slowed movement. This disease involves degeneration of dopamine-releasing neurons in the basal ganglia of the forebrain, which are crucial for motor control.
parsing The dissection of a complex stimulus into meaningful parts.
partial-reinforcement effect The fact that a response is much harder to extinguish if it was acquired during partial rather than continuous reinforcement. A condition in which repeated responses are reinforced only some of the time.
participant observation: research that requires an observer to become a member of his or her subjects' community.
parturition: the act of bringing forth young; childbirth.
parvo cells Ganglion cells found throughout the retina that, because of their sensitivity to differences in hue, are particularly suited to the perception of color and form.
passion: intense feelings of physiological arousal and excitement.
passionate love a state of intense longing for union with another. Passionate lovers are absorbed in one another, feel ecstatic at attaining their partner's love, and are disconsolate on losing it. A state of intense longing for union with another.
passive euthanasia: the deliberate withdrawal or withholding of life-sustaining treatment that may otherwise prolong the life of the dying person.
pathogen Disease-producing microbes, including viruses, fungi, and bacteria, that can trigger the production of fever. In evolutionary terms, defense against pathogens may be the driving force behind sexual reproduction.
pathology model As used in the text, the pathology model describes a general conception of mental disorders which holds that (1) one can generally distinguish signs and symptoms from their underlying causes, and (2) these causes may be regarded as a form of disease. See alsolearning model, medical model, psychoanalytic model.
pattern recognition The process by which the perceptual system matches the form of a figure against the figure as represented in memory.
pattern theory The theory that a stimulus attribute is not coded by being sent along specific sensory fibers, but rather by a specific pattern of firing of all the relevant sensory fibers.
payoff matrix (1) In a signal detection experiment, a table that shows the costs and benefits of each of the four possible outcomes: a hit, reporting the stimulus when it is present; a correct negative, reporting it as absent when it is in fact absent; a miss, failing to report it when it is present; and a false alarm, reporting it as present when it is not.
peak experience As Maslow considered it, a profound and deeply felt moment in a person’s life, sometimes said to be more common in self-actualized persons than in others. See alsohierarchy of needs, self-actualization.
pedophilia: an abnormal condition in which an adult has a sexual desire for children.
peer pressure: to be forced or compelled to do something by one's peers.
penis envy In psychoanalytic theory, the wish for a penis that normally ensues in females as part of the Elektra complex.
perceived locus of control A person’s belief about the source of outcomes that befall her. That perceived source (locus) may be internal (the result of something she did) or external (the result of forces out of her control).
percentile rank The percentage of all the scores in a distribution that lie below a given score.
perception: the psychological process by which the human brain processes the sensory data collected by the sensory organs.
perceptual adaptation The gradual adjustment to various distortions of the perceptual world.
perceptual constancies Certain constant attributes of a distal object, such as its shape and size, that we are able to perceive despite vagaries of the proximal stimulus.
perceptual hypothesis The perceiver’s assumption about what the stimulus is, tested as the perceptual system analyzes the stimulus for appropriate features.
perceptual parsing The process of grouping various visual elements of a scene appropriately, deciding which elements go together and which do not.
perineum: the region of the body between the thighs, at the outlet of the pelvis; specifically, the small area between the anus and the vulva in the female or between the anus and the scrotum in the male.
period of concrete operationsSeeconcrete operations period.
period of formal operationsSeeformal operations period.
peripheral nervous system The parts of the nervous system outside the central nervous system, including the cranial and spinal nerves that exit the skull and spinal column, respectively.
Peripheral route to persuasion Persuasion that occurs when people do not think carefully about a communication and instead are influenced by cues that are irrelevant to the content or quality of the communication. Persuasion that occurs when people are influenced by incidental cues, such as a speaker's attractiveness. The path of persuasion when the issue being discussed does not matter much to the listener or the listener is distracted. Relatively superficial factors (whether the person offering the arguments is attractive, the number of arguments offered) will determine persuasiveness. Convincing arguments are less important. See alsocentral route to persuasion.
periphery In vision, the area toward the outside of the retina that has a high concentration of rods, is sensitive to dim light, and is responsible for colorless sensations.
permastore Near-permanent retention of some kinds of items in memory, mostly involving semantic or general knowledge (e.g., multiplication tables, names of family members).
permissive parents: parents who demonstrate high parental warmth and low parental control when interacting with their children. A parental style in which parents try not to assert their authority and impose few restrictions or demands on their children.
perseveration The tendency to repeat the same response inappropriately, typically accompanying the defects in strategy formation often observed with prefrontal lesions.
Personal distress An unpleasant state of arousal in which people are preoccupied with their own emotions of anxiety, fear, or helplessness upon viewing a victim's plight.
personal space the buffer zone we like to maintain around our bodies. Its size depends on our familiarity with whoever is near us. The physical region all around us whose intrusion we guard against. This aspect of human behavior has been likened to territoriality in animals.
personality inventories Paper-and-pencil tests of personality that ask questions about feelings, desires, or customary behavior.
personality: habitual patterns and qualities of behavior of any individual as expressed by physical and mental activities and attitudes; distinctive individual qualities.
person-by-situation interaction A view of influences on personality which holds that a person’s behavior is the joint outcome of his predis-positions and the particular situations he encounters. Thus, some people may on average be equally fearful, but while one is afraid of meeting people but unafraid of large animals, another may be afraid of large animals but be unafraid of meeting people. See alsoreciprocal interaction, situationism.
persuasion the process by which a message induces change in beliefs, attitudes, or behaviors. The process of consciously attempting to change attitudes through the transmission of some message.
persuasive communications Messages that openly try to convince us to act a certain way or to hold a particular belief.
PET (positron emission tomography) scan A technique for examining brain function by observing the degree of metabolic activity of different regions of the brain.
petting: sexual activities other than intercourse.
Ph.D.- Doctor of Philosophy - usually a Psychologist
phallic stage In psychoanalytic theory, the stage of psychosexual development during which the child begins to regard his or her genitals as a major source of gratification. Designating or of the third stage of psychosexual development in which interest centers around the genital organs.
phenothiazines A kind of classical antipsychotic medication, such as Thorazine, that seems to be effective in alleviating the major positive signs and symptoms of schizophrenia.
phenotype The overt appearance and behavior of an organism, regardless of its genetic blueprint. See alsogenotype.
phenylalanine An amino acid that cannot be transformed due to an enzyme deficiency in those with phenylketonuria (PKU). In an infant with PKU, phenylalanine is converted into a toxic agent that accumulates in an infant’s bloodstream and damages the developing nervous system.
phenylketonuria (PKU) A condition in which one lacks the gene that enables one to metabolize phenylalanine. If detected early enough, this condition can be treated by means of a special diet. If not detected early, this disorder can cause a severe form of retardation. A genetic disorder of phenylalanine metabolism, which, if untreated, causes severe mental retardation in infants through the accumulation of toxic metabolic products.
pheromones Special chemicals secreted by many animals that trigger particular reactions in members of the same species. Humans seem to have a pheromone that regulates the timing of menstruation in females.
phi phenomenonSeeapparent movement.
phobia An anxiety disorder that is characterized by an intense and, at least on the surface, irrational fear. See alsoanxiety disorders, social phobia, specific phobia.
phoneme The smallest significant unit of sound in a language. In English, it corresponds roughly to a letter of the alphabet (e.g., apt, tap, and pat are all made up of the same phonemes).
phonology The rules in a language that govern the sequence in which phonemes can be arranged.
photoreceptor One of the visual pigment-filled light-sensitive cells at the back of the retina, whether rods or cones.
phrase A sequence of words within a sentence that functions as a unit.
phrase structure description A tree diagram that shows the hierarchical structure of a sentence. The descending branches of the tree correspond to smaller and smaller units of sentence structure.
phrase structure The organization of sentences into phrases. Surface structure is the phrase organization of sentences as they are spoken or written. Underlying structure is the phrase organization that describes the meaning of parts of the sentence, such as doer, action, and done-to.
phrenology An early nineteenth-century fad that involved palpating bumps and indentations on the head in order to judge the examinee’s intellectual and personality traits. A forerunner of modern theories of cerebral localization, phrenology nonetheless had no validity.
Physical attractiveness stereotype The belief that physically attractive individuals possess socially desirable personality traits and lead happier lives than less attractive persons.
physical development: the biological changes that humans undergo as they age.
physical disability: any physical defect, change, difficulty, or condition that has the potential to disrupt daily living.
physical intimacy: mutual affection and sexual activity.
physical-attractiveness stereotype the presumption that physically attractive people possess other socially desirable traits as well: What is beautiful is good.
pictorial cues The monocular depth cues (such as, interposition, linear perspective, and relative size) that the eye exploits as an optical consequence of the projection of a three-dimensional world on a flat surface.
piloerection Erection of the hairs on the surface of the skin, used by furry animals to conserve heat and by some animals (e.g., cats) as a threat display. In humans, piloerection is manifest as "goosebumps," although, since humans lack full body hair, the response is largely vestigial.
pitch The psychological dimension of sound that corresponds to frequency; as frequency increases, pitch appears to rise.
pituitary gland An endocrine gland that is actually a functional extension of the hypothalamus. The pituitary gland is often called the master gland because many of its secretions trigger hormone secretions in other glands.
place theory A theory of pitch proposed by Hermann von Helmholtz which states that different regions of the basilar membrane in the cochlea respond to different sound frequencies. The nervous system interprets the excitation from different basilar regions as different pitches.
Placebo effect A situation where people experience some change or improvement from an empty, fake, or ineffectual treatment. The actual medical or psychological benefits of a treatment administered to a patient who believes it has therapeutic powers even though it actually has none. In medical practice, a term for a chemically inert substance that produces real medical benefits because the patient believes it will help her.
placenta: a vascular organ that is connected to the embryo by the umbilical cord and that is discharged shortly after birth; the structure serves to provide nourishment for and eliminate wastes from the fetus.
placental lactogen: a hormone produced by the placenta that prepares the mammary glands to secrete milk.
plasticity The changeability of a trait or behavior with experience (e.g., eye color shows little plasticity, while hair color shows considerably more).
pleasure center According to some theorists, a special region of the brain that is triggered whenever any motive is satisfied.
pleasure principle In Freud’s theory, the id’s sole law, that of obtaining immediate satisfaction regardless of the circumstances and whatever the cost.
pluralistic ignorance a false impression of how other people are thinking, feeling, or responding. A situation in which individuals in a group don’t know that there are others in the group who share their feelings.
polyandry A type of polygamous mating system in which one female monopolizes the reproductive efforts of several males.
polygamy Any mating system, including polyandry and polygymy, in which one member of a sex monopolizes the reproductive efforts of several members of the other sex.
polygenic inheritance Inheritance of an attribute whose expression is controlled not by one but by many gene pairs.
polygraph A device for measuring heart rate, respiration, and galvanic skin response. Sometimes called a "lie detector," the polygraph can only detect signs of physiological stress; whether one is lying is an interpretation made by the polygraph examiner.
polygyny A type of polygamous mating system in which one male monopolizes the reproductive efforts of several females.
pons The topmost portion of the hindbrain just above the medulla and in front of the cerebellum; it is involved in coordinating facial sensations and muscular actions, and in regulating sleep and arousal.
population The entire group of research participants (or test trials) about which the investigator wants to draw conclusions. See alsosample. A body of persons having qualities or characteristics in common.
Pornography The combination of sexual material with abuse or degradation in a manner that appears to endorse, condone, or encourage such behavior.
positive feedbackSeefeedback system.
positive reinforcement The process whereby the delivery of a stimulus contingent upon an operant response acts to increase the subsequent probability of that response. It also refers to the procedure in which consequences are arranged to produce increases in operant responding. T he rewarding of acceptable behaviors.
positive symptoms of schizophrenia Symptoms that involve behavior or thinking that is either less pronounced or nonexistent in normal individuals, such as hallucinations, delusions, or bizarre behavior. See alsonegative symptoms of schizophrenia.
Positivity bias The tendency for people to evaluate individual human beings more positively than groups or impersonal objects.
positron emission tomography scanSeePET scan.
possible selves images of what we dream of or dread becoming in the future.
postconventional morality: moral reasoning and behavior characterized by accepting the relative and changeable nature of rules and laws, and conscience-directed concern with human rights.
postformal thinking: the objective use of practical common sense to deal with unclear problems.
postmature baby: an infant who is born 2 or more weeks after its due date.
postpartum stage: the period following childbirth.
postsynaptic membrane The membrane of the receiving cell across the synaptic gap that contains specialized receptor sites.
postsynaptic neuron The cell receiving a neural message at the synapse.
post-traumatic stress disorder (PTSD) A chronic, sometimes lifelong disorder that has its onset some time after an especially stressful traumatic event. Symptoms include dissociation, recurrent nightmares, flashbacks, and sleep disturbances. See alsoacute stress disorder, anxiety disorders, dissociation.
potentiation In motivation, the tendency to make some behaviors, perceptions, and feelings more probable than others. See alsolong-term potentiation.
practical intelligence The intelligence required to solve everyday problems.
preadolescence: the period of childhood between ages 10 and 11.
preconventional morality: moral reasoning and behavior based on rules and fear of punishment and nonempathetic self-interest.
precursor A substance required for the chemical manufacture of a neurotransmitter.
predictive validity A measure of whether a test assesses what is intended that is based on the correlation between the test score and some external criterion (e.g., a correlation between a scholastic aptitude test score and college grades).
prefrontal area The frontmost portion of the frontal lobes, which is involved in working memory, strategy formation, and response inhibition.
prefrontal cortex: the most anterior (front) portion of the frontal lobes; appears to be responsible for personality.
prefrontal lobotomy A neurosurgical treatment that surgically cuts the connections between the prefrontal areas of the frontal lobes and the rest of the brain. Once used widely (and mostly unsuccessfully) for many mental disorders but now performed very rarely.
pregnancy: the condition, quality, or period of having (an) offspring developing in the uterus.
Prejudice A negative attitude directed toward people simply because they are members of a specific social group. A negative prejudgment of a group and its individual members. Suspicion, intolerance, or irrational hatred of other races, creeds, regions, occupations, and so on.
premature (preterm) birth: a birth that occurs before a gestation of 37 weeks.
premise An assumption or stipulation that precedes deductive reasoning.
preoperational period In Piaget’s theory, the period from about ages two to six during which children come to represent actions and objects internally but cannot systematically manipulate these representations or relate them to each other. The child is therefore unable to conserve quantity across perceptual transformations and also is unable to take points of view other than his own.
preoperational stage: according to Piaget, the stage of cognitive development that occurs between ages 2 and 7.
preparedness A built-in predisposition to form certain associations more readily than others.
preparedness theory of phobias The theory that phobias grow out of a built-in predisposition (preparedness) to learn to fear certain stimuli (e.g., snakes and spiders) that may have posed serious dangers to our primate ancestors.
presbycusis: difficulty hearing high-pitched sounds.
presbyopia: a form of farsightedness occurring after middle age, caused by a diminished elasticity of the crystalline lens.
prescriptionism The view that psychotherapeutic treatments for mental disorders may ultimately be like prescriptions for medications: tailored to both the disorder and the individual patient.
prescriptive rules Rules prescribed by "authorities" about how people ought to speak and write that often fail to conform to the facts about how people actually talk and understand. This is in contrast to the structural principles of a language, which describe (rather than prescribe) the principles native speakers of a language actually use when arranging their words into sentences.
presynaptic facilitation A process that underlies many kinds of learning, documented in studies of Aplysia. It occurs when learning results in the increased readiness of presynaptic neurons to fire.
presynaptic neuron The cell that shoots a neurotransmitter across the synaptic gap.
primacy effect In free recall, the tendency to recall the first items on a list more readily than those in the middle. In forming an impression of another person, the tendency to give greater weight to attributes noted at the outset than to those noted later. Other things being equal, information presented first usually has the most influence. The tendency for the first information received to carry more weight than later information on one's overall impression.
primary messenger The neurochemicals responsible for neuron-to-neuron communication in chemical synapses, i.e., neurotransmitters. Primary messengers are contrasted with second messengers, those neurochemicals responsible for communication within neurons.
primary motor projection area A strip of cortex located at the back of the frontal lobe just ahead of the primary sensory projection area in the parietal lobe. This region is the primary projection area for muscular movements.
primary projection areas Regions of the cortex that serve as receiving stations for sensory information or as dispatching stations for motor commands.
primary sex characteristics: any of the physical characteristics differentiating male and female individuals; directly responsible for reproduction.
primary somatosensory projection area A strip of cortex located at the front of the parietal lobe just behind the primary motor area in the frontal lobe. This region is the primary projection area for bodily sensations, including touch, pain, and temperature.
priming activating particular associations in memory.
priming effect Phenomenon wherein giving a participant advance knowledge about or exposure to a stimulus can increase the ease of its subsequent recall or recognition.
primitive features Attributes of an object (such as its location, contour, color, and shape) that are first detected separately and then coordinated to enable identification of the object.
prisoner’s dilemma A particular arrangement of payoffs in a two-person situation in which each individual has to choose between two alternatives without knowing the other’s choice. The payoff structure is arranged such that the optimal strategy for each person depends upon whether she can trust the other or not. If trust is possible, the payoffs for each will be considerably higher than if there is no trust.
Private self-awareness A psychological state in which one is aware of one's hidden private self-aspects.
Private self-consciousness The tendency to be aware of the covert, private aspects of the self.
proactive inhibition The lessened ability to recall new material because of material learned previously. See alsoretroactive inhibition.
probability of response The likelihood of the occurrence of a response; it is a common measure of response strength in classical and operant conditioning.
procedural knowledgeSeedeclarative knowledge.
Process: the living expression of the organism in the moment - i.e. what you are feeling, sensing, experiencing in the immediate present.
productive language: an ability to use the spoken or written word.
progesterone A female sex hormone that dominates the latter phase of the female cycle during which the uterine walls thicken to receive the embryo. A hormone secreted by the corpus luteum, active in preparing the uterus for the reception and development of the fertilized ovum and the mammary glands for milk secretion.
projection areasSeeprimary projection areas.
projection In psychoanalytic theory, a mechanism of defense in which various forbidden thoughts and impulses are attributed to another person rather than the self, thus warding off some anxiety (e.g., "I hate you" becomes "You hate me").
projective techniques Sometimes called unstructured personality tests. Methods of assessing personality that use relatively ambiguous stimuli in order to elicit responses that are unguarded and authentic. The most common projective techniques are the TAT and the Rorschach inkblot test. See alsopersonality inventories.
promiscuity: characterized by a lack of discrimination; specifically, engaging in sexual intercourse indiscriminately or with many persons.
propagation The spread of the action potential down an axon, caused by successive destabilizations of the neuronal membrane.
prosocial behavior positive, constructive, helpful social behavior; the opposite of antisocial behavior. Voluntary behavior that is carried out to benefit another person. The capacity to help, cooperate, and share with others.
prosopagnosia The inability to recognize faces, usually produced by lesions in the parietal lobes.
prototype The typical example of a category of (e.g., a robin is a prototypical bird).
prototype theory of meaning The theory that concepts are formed around average exemplars rather than lists of single attributes.
proximal stimulusSeedistal stimulus.
proximate cause The immediate cause in a chain of causation. The proximate cause of a person’s death might be a stroke, but why he suffered a stroke requires further investigation. See alsoultimate cause.
proximity (1) In perception, the closeness of two figures. The closer together they are, the more they will tend to be grouped together perceptually; (2) the nearness of people, which is one of the most important determinants of attraction and liking. Geographical nearness. Proximity (more precisely, "functional distance") powerfully predicts liking. The location of people relative to one another.
pseudohermaphroditism The most common kind of intersexuality, in which individuals have ambiguous genitalia. See alsointersexual.
psychiatric disability: a mental illness or psychological disturbance, causing a person to struggle with mild to incapacitating emotional problems and limitations that are often caused by either anxiety or affective disorders.
psychoanalysis (1) A theory of both normal and abnormal human personality development, formulated by Freud, whose key assertions include unconscious conflict and early psychosexual development. (2) A method of therapy that draws heavily on this theory of personality. Its main aim is to have the patient gain insight into her own, presently unconscious, thoughts and feelings. Therapeutic tools employed toward this end include free association, interpretation, and the appropriate use of the transference relationship between patient and analyst. See alsofree association, transference.
psychoanalytic model As defined in the text, a subcategory of the pathology model which holds (1) that the underlying pathology is a constellation of unconscious conflicts and defenses against anxiety, usually rooted in early childhood, and (2) that treatment should be by some form of psychotherapy based on psychoanalytic principles.
psychodynamic approach to personality An approach to personality originally derived from psychoanalytic theory that asserts that personality differences are based on unconscious (dynamic) conflicts within the individual. See alsobehavioral-cognitive approach, humanistic approach, situationism, sociocultural approach, trait theory.
psychodynamic model An approach to mental disorders which holds that they are the end-products of internal psychological conflicts that generally originate in one’s childhood experiences. See alsolearning model, medical model, pathology model.
psychogenic disorders Disorders whose origins are psychological rather than organic (e.g., phobias). See alsosomatogenic mental disorders.
psychogenic symptoms Symptoms believed to result from some psychological cause rather than from actual tissue damage.
psycholinguists: specialists in the study of language.
psychological intensity The magnitude of a stimulus as it is perceived, not in terms of its physical attributes.
psychological intimacy: the sharing of feelings and thoughts.
Psychological Structure "...We have learned that no dynamics of forces alone can explain what a human being does. We know from biology and from social studies also, that functions, once established, structuralize, i.e., they form steady states which are resistive to change. In psychololgical life too we find such automatized functions, which do not have to be created anew, which behave like structures. The most common ones of these are know under the names ego, superego, but grammar, syntax, logic as well as concepts, anticipations and organized bodies of knowledge, whether about abstractions or material matters also belong here"
psychometric approach to intelligence An attempt to understand the nature of intelligence by studying the pattern of results obtained on intelligence tests.
psychopathology (1) The study of mental disorders, or (2) mental disorder itself.
psychophysics An approach to understanding perception that relates the characteristics of physical stimuli to attributes of the sensory experience they produce.
psychophysiological disorders In these disorders (formerly called psychosomatic), the primary manifestations involve genuine organic damage, but their onset or severity is heavily influenced by psychological factors (e.g., coronary heart disease).
psychosexual development In psychoanalytic theory, the description of the progressive stages in the way the child gains pleasure as he grows into adulthood, defined by the zone of the body through which maximal pleasure is derived (oral, anal, genital) and by the object toward which this pleasurable feeling is directed (mother, father, adult sexual partner). See alsoanal stage, genital stage, oral stage, phallic stage.
psychosexual development: Freud's theory that children systematically move through oral, anal, phallic, and latency stages before reaching mature adult sexuality in the genital stage.
psychosis Loss of contact with reality (most often evidenced as delusions or hallucinations), as can occur in severe cases of many kinds of mental disorders such as mania, major depression, or schizophrenia.
psychosocial crises In Erik Erikson’s theory, a series of crises through which all persons must pass as they go through their life cycle (e.g., the identity crisis during which adolescents or young adults try to establish the separation between themselves and their parents).
psychosocial: of or pertaining to the psychological development of the individual in relation to his or her social environment.
psychosomatic disordersSeepsychophysiological disorders.
psychosurgery Neurosurgery performed to alleviate manifestations of mental disorders that cannot be brought under control using psychotherapy, medication, or other standard treatments. Psychosurgery can be helpful in severe cases of, for example, obsessive-compulsive disorder.
psychotherapy As used here, a collective term for all forms of treatment that use psychological rather than somatic methods.
psychoticism In Hans Eysenck’s personality system, a trait dimension related to aggressiveness, antisocial actions, coldness, impulsivity, and self-centeredness.
PsyD - Doctor of Psychology
puberty: the stage of physical development when secondary sex characteristics develop and sexual reproduction first becomes possible: in common law, the age of puberty is generally fixed at fourteen for boys and twelve for girls.
Public self-awareness A psychological state in which one is aware of one's public self-aspects.
Public self-consciousness The tendency to be aware of the publicly displayed aspects of the self.
Punishment Adverse stimuli offered following a given behavior that decreases the probability that the behavior will be repeated.
punishment training An instrumental training procedure in which a response is suppressed by having its occurrence followed by an aversive event. See alsoavoidance learning, escape learning.
punishment: the infliction of some penalty on a wrongdoer.
puzzle box An apparatus used by Edward Thorndike to demonstrate trial-and-error learning in cats. Animals were required to perform a simple action in order to escape the puzzle box and obtain food.
pyramidal system One of the two motor systems that originates in the motor cortex of the brain and sends its tracts directly to the motoneurons that activate the muscles. The pyramidal system is more recent in evolutionary terms and orchestrates the body’s more precise movements.
pyrogens Chemicals released into the bloodstream at sites of bacterial or viral invasion that stimulate special receptors in the anterior part of the hypothalamus and produce fever, which probably represents the body’s effort to kill off the invading pathogens by temporarily overheating.
qualitative research: research in which information collected from respondents takes the form of verbal descriptions or direct observations of events. Research in which information is collected from respondents and converted into numbers.
questionnaire: a written or printed form used in gathering information on some subject or subjects, consisting of a set of questions to be submitted to one or more persons.
quickening: the stage of pregnancy in which the movement of the fetus can be felt for the first time.