Vocabulary

Absolute threshold: The smallest amount of stimulation needed for detection by a sense.
Acceptance and commitment therapy: A therapeutic approach designed to foster nonjudgmental observation of one’s own mental processes.
Action potential: A transient all-or-nothing electrical current that is conducted down the axon when the membrane potential reaches the threshold of excitation.
Afferent nerves: Nerves that carry messages to the brain or spinal cord.
Agnosia: Loss of the ability to perceive stimuli.
Agnosias: Due to damage of Wernicke’s area. An inability to recognize objects, words, or faces.
Agoraphobia: A sort of anxiety disorder distinguished by feelings that a place is uncomfortable or may be unsafe because it is significantly open or crowded.
Agreeableness: A personality trait that reflects a person’s tendency to be compassionate, cooperative, warm, and caring to others. People low in agreeableness tend to be rude, hostile, and to pursue their own interests over those of others.
Anhedonia: Loss of interest or pleasure in activities one previously found enjoyable or rewarding.
Anosmia: Loss of the ability to smell.
Anterograde amnesia: Inability to form new memories for facts and events after the onset of amnesia.
Anxiety: A mood state characterized by negative affect, muscle tension, and physical arousal in which a person apprehensively anticipates future danger or misfortune.
Aphasia: Due to damage of the Broca’s area. An inability to produce or understand words.
Arcuate fasciculus: A fiber tract that connects Wernicke’s and Broca’s speech areas.
Attitude: A way of thinking or feeling about a target that is often reflected in a person’s behavior. Examples of attitude targets are individuals, concepts, and groups.
Attraction: The psychological process of being sexually interested in another person. This can include, for example, physical attraction, first impressions, and dating rituals.
Attributional style: The tendency by which a person infers the cause or meaning of behaviors or events.
Audition: Ability to process auditory stimuli. Also called hearing.
Auditory canal: Tube running from the outer ear to the middle ear.
Auditory hair cells: Receptors in the cochlea that transduce sound into electrical potentials.
Authoritative: A parenting style characterized by high (but reasonable) expectations for children’s behavior, good communication, warmth and nurturance, and the use of reasoning (rather than coercion) as preferred responses to children’s misbehavior.
Autobiographical memory: Memory for the events of one’s life.
Automatic thoughts: Thoughts that occur spontaneously; often used to describe problematic thoughts that maintain mental disorders.
Autonomic nervous system: A part of the peripheral nervous system that connects to glands and smooth muscles. Consists of sympathetic and parasympathetic divisions.
Axon: Part of the neuron that extends off the soma, splitting several times to connect with other neurons; main output of the neuron.
Big Five: Five, broad general traits that are included in many prominent models of personality. The five traits are neuroticism (those high on this trait are prone to feeling sad, worried, anxious, and dissatisfied with themselves), extraversion (high scorers are friendly, assertive, outgoing, cheerful, and energetic), openness to experience (those high on this trait are tolerant, intellectually curious, imaginative, and artistic), agreeableness (high scorers are polite, considerate, cooperative, honest, and trusting), and conscientiousness (those high on this trait are responsible, cautious, organized, disciplined, and achievement-oriented).
Binocular disparity: Difference is images processed by the left and right eyes.
Binocular vision: Our ability to perceive 3D and depth because of the difference between the images on each of our retinas.
Biological vulnerability: A specific genetic and neurobiological factor that might predispose someone to develop anxiety disorders.
Blind to the research hypothesis: When participants in research are not aware of what is being studied.
Blocking: In classical conditioning, the finding that no conditioning occurs to a stimulus if it is combined with a previously conditioned stimulus during conditioning trials. Suggests that information, surprise value, or prediction error is important in conditioning.
Bottom-up processing: Building up to perceptual experience from individual pieces.
Broca’s area: An area in the frontal lobe of the left hemisphere. Implicated in language production.
Categorize: To sort or arrange different items into classes or categories.
Cell membrane: A bi-lipid layer of molecules that separates the cell from the surrounding extracellular fluid.
Central sulcus: The major fissure that divides the frontal and the parietal lobes.
Cerebellum: A nervous system structure behind and below the cerebrum. Controls motor movement coordination, balance, equilibrium, and muscle tone.
Cerebrum: Consists of left and right hemispheres that sit at the top of the nervous system and engages in a variety of higher-order functions.
Chemical senses: Our ability to process the environmental stimuli of smell and taste.
Chronic stress: Discrete or related problematic events and conditions which persist over time and result in prolonged activation of the biological and/or psychological stress response (e.g., unemployment, ongoing health difficulties, marital discord).
Chutes and Ladders: A numerical board game that seems to be useful for building numerical knowledge.
Cingulate gyrus: A medial cortical portion of the nervous tissue that is a part of the limbic system.
Classical conditioning: The procedure in which an initially neutral stimulus (the conditioned stimulus, or CS) is paired with an unconditioned stimulus (or US). The result is that the conditioned stimulus begins to elicit a conditioned response (CR). Classical conditioning is nowadays considered important as both a behavioral phenomenon and as a method to study simple associative learning. Same as Pavlovian conditioning.
Cochlea: Spiral bone structure in the inner ear containing auditory hair cells.
Cognitive bias modification: Using exercises (e.g., computer games) to change problematic thinking habits.
Cognitive-behavioral therapy (CBT): A family of approaches with the goal of changing the thoughts and behaviors that influence psychopathology.
Collective self-esteem: Feelings of self-worth that are based on evaluation of relationships with others and membership in social groups.
Common knowledge effect: The tendency for groups to spend more time discussing information that all members know (shared information) and less time examining information that only a few members know (unshared).
Comorbidity: Describes a state of having more than one psychological or physical disorder at a given time.
Computerized axial tomography: A noninvasive brain-scanning procedure that uses X-ray absorption around the head.
Concrete operations stage: Piagetian stage between ages 7 and 12 when children can think logically about concrete situations but not engage in systematic scientific reasoning.
Conditioned compensatory response: In classical conditioning, a conditioned response that opposes, rather than is the same as, the unconditioned response. It functions to reduce the strength of the unconditioned response. Often seen in conditioning when drugs are used as unconditioned stimuli.
Conditioned response: A learned reaction following classical conditioning, or the process by which an event that automatically elicits a response is repeatedly paired with another neutral stimulus (conditioned stimulus), resulting in the ability of the neutral stimulus to elicit the same response on its own.
Conditioned response (CR): The response that is elicited by the conditioned stimulus after classical conditioning has taken place.
Conditioned stimulus (CS): An initially neutral stimulus (like a bell, light, or tone) that elicits a conditioned response after it has been associated with an unconditioned stimulus.
Cones: Photoreceptors of the retina sensitive to color. Located primarily in the fovea.
Conformity: Changing one’s attitude or behavior to match a perceived social norm.
Confounds: Factors that undermine the ability to draw causal inferences from an experiment.
Conscience: The cognitive, emotional, and social influences that cause young children to create and act consistently with internal standards of conduct.
Conscientiousness: A personality trait that reflects a person’s tendency to be careful, organized, hardworking, and to follow rules.
Conservation problems: Problems pioneered by Piaget in which physical transformation of an object or set of objects changes a perceptually salient dimension but not the quantity that is being asked about.
Consolidation: The process occurring after encoding that is believed to stabilize memory traces.
Consolidation: Process by which a memory trace is stabilized and transformed into a more durable form.
Context: Stimuli that are in the background whenever learning occurs. For instance, the Skinner box or room in which learning takes place is the classic example of a context. However, “context” can also be provided by internal stimuli, such as the sensory effects of drugs (e.g., being under the influence of alcohol has stimulus properties that provide a context) and mood states (e.g., being happy or sad). It can also be provided by a specific period in time—the passage of time is sometimes said to change the “temporal context.”
Continuous development: Ways in which development occurs in a gradual incremental manner, rather than through sudden jumps.
Continuous distributions: Characteristics can go from low to high, with all different intermediate values possible. One does not simply have the trait or not have it, but can possess varying amounts of it.
Correlation: Measures the association between two variables, or how they go together.
Cue overload principle: The principle stating that the more memories that are associated to a particular retrieval cue, the less effective the cue will be in prompting retrieval of any one memory.
Culture of honor: A culture in which personal or family reputation is especially important.
Dark adaptation: Adjustment of eye to low levels of light.
Decay: The fading of memories with the passage of time.
Declarative memory: Conscious memories for facts and events.
Dendrite: Part of a neuron that extends away from the cell body and is the main input to the neuron.
Dependent variable: The variable the researcher measures but does not manipulate in an experiment.
Depth perception: The ability to actively perceive the distance from oneself of objects in the environment.
Dialectical behavior therapy (DBT): A treatment often used for borderline personality disorder that incorporates both cognitive-behavioral and mindfulness elements.
Dialectical worldview: A perspective in DBT that emphasizes the joint importance of change and acceptance.
Differential threshold (or difference threshold): The smallest difference needed in order to differentiate two stimuli. (See Just Noticeable Difference (JND))
Diffusion: The force on molecules to move from areas of high concentration to areas of low concentration.
Discontinuous development: Discontinuous development
Discrimination: Discrimination is behavior that advantages or disadvantages people merely based on their group membership.
Discriminative stimulus: In operant conditioning, a stimulus that signals whether the response will be reinforced. It is said to “set the occasion” for the operant response.
Dissociative amnesia: Loss of autobiographical memories from a period in the past in the absence of brain injury or disease.
Distinctiveness: The principle that unusual events (in a context of similar events) will be recalled and recognized better than uniform (nondistinctive) events.
Dorsal pathway: Pathway of visual processing. The “where” pathway.
Early adversity: Single or multiple acute or chronic stressful events, which may be biological or psychological in nature (e.g., poverty, abuse, childhood illness or injury), occurring during childhood and resulting in a biological and/or psychological stress response.
Ectoderm: The outermost layer of a developing fetus.
Efferent nerves: Nerves that carry messages from the brain to glands and organs in the periphery.
Effortful control: A temperament quality that enables children to be more successful in motivated self-regulation.
Ego defenses: Mental strategies, rooted in the ego, that we use to manage anxiety when we feel threatened (some examples include repression, denial, sublimation, and reaction formation).
Electroencephalography: A technique that is used to measure gross electrical activity of the brain by placing electrodes on the scalp.
Electrostatic pressure: The force on two ions with similar charge to repel each other; the force of two ions with opposite charge to attract to one another.
Empirical methods: Approaches to inquiry that are tied to actual measurement and observation.
Encoding: The initial experience of perceiving and learning events.
Encoding: Process by which information gets into memory.
Encoding specificity principle: The hypothesis that a retrieval cue will be effective to the extent that information encoded from the cue overlaps or matches information in the engram or memory trace.
Engrams: A term indicating the change in the nervous system representing an event; also, memory trace.
Episodic memory: Memory for events in a particular time and place.
Ethics: Professional guidelines that offer researchers a template for making decisions that protect research participants from potential harm and that help steer scientists away from conflicts of interest or other situations that might compromise the integrity of their research.
Event-related potentials: A physiological measure of large electrical change in the brain produced by sensory stimulation or motor responses.
Excitatory postsynaptic potentials: A depolarizing postsynaptic current that causes the membrane potential to become more positive and move towards the threshold of excitation.
Experimenter expectations: When the experimenter’s expectations influence the outcome of a study.
Exposure therapy: A form of intervention in which the patient engages with a problematic (usually feared) situation without avoidance or escape.
External cues: Stimuli in the outside world that serve as triggers for anxiety or as reminders of past traumatic events.
Extinction: Decrease in the strength of a learned behavior that occurs when the conditioned stimulus is presented without the unconditioned stimulus (in classical conditioning) or when the behavior is no longer reinforced (in instrumental conditioning). The term describes both the procedure (the US or reinforcer is no longer presented) as well as the result of the procedure (the learned response declines). Behaviors that have been reduced in strength through extinction are said to be “extinguished.”
Extraversion: A personality trait that reflects a person’s tendency to be sociable, outgoing, active, and assertive.
Facets: Broad personality traits can be broken down into narrower facets or aspects of the trait. For example, extraversion has several facets, such as sociability, dominance, risk-taking and so forth.
Factor analysis: A statistical technique for grouping similar things together according to how highly they are associated.
Family Stress Model: A description of the negative effects of family financial difficulty on child adjustment through the effects of economic stress on parents’ depressed mood, increased marital problems, and poor parenting.
Fear conditioning: A type of classical or Pavlovian conditioning in which the conditioned stimulus (CS) is associated with an aversive unconditioned stimulus (US), such as a foot shock. As a consequence of learning, the CS comes to evoke fear. The phenomenon is thought to be involved in the development of anxiety disorders in humans.
Fight or flight response: A biological reaction to alarming stressors that prepares the body to resist or escape a threat.
Five-Factor Model: (also called the Big Five) The Five-Factor Model is a widely accepted model of personality traits. Advocates of the model believe that much of the variability in people’s thoughts, feelings, and behaviors can be summarized with five broad traits. These five traits are Openness, Conscientiousness, Extraversion, Agreeableness, and Neuroticism.
Flashback: Sudden, intense re-experiencing of a previous event, usually trauma-related.
Flashbulb memory: Vivid personal memories of receiving the news of some momentous (and usually emotional) event.
Flavor: The combination of smell and taste.
Forebrain: A part of the nervous system that contains the cerebral hemispheres, thalamus, and hypothalamus.
Formal operations stage: Piagetian stage starting at age 12 years and continuing for the rest of life, in which adolescents may gain the reasoning powers of educated adults.
Fornix: (plural form, fornices) A nerve fiber tract that connects the hippocampus to mammillary bodies.
Free association: In psychodynamic therapy, a process in which the patient reports all thoughts that come to mind without censorship, and these thoughts are interpreted by the therapist.
Frontal lobe: The most forward region (close to forehead) of the cerebral hemispheres.
Functional magnetic resonance imaging: (or fMRI) A noninvasive brain-imaging technique that registers changes in blood flow in the brain during a given task (also see magnetic resonance imaging).
Fundamental attribution error: The tendency to emphasize another person’s personality traits when describing that person’s motives and behaviors and overlooking the influence of situational factors.
G: Short for “general factor” and is often used to be synonymous with intelligence itself.
Gender schemas: Organized beliefs and expectations about maleness and femaleness that guide children’s thinking about gender.
Generalized anxiety disorder (GAD): Excessive worry about everyday things that is at a level that is out of proportion to the specific causes of worry.
Globus pallidus: A nucleus of the basal ganglia.
Goal-directed behavior: Instrumental behavior that is influenced by the animal’s knowledge of the association between the behavior and its consequence and the current value of the consequence. Sensitive to the reinforcer devaluation effect.
Goodness of fit: The match or synchrony between a child’s temperament and characteristics of parental care that contributes to positive or negative personality development. A good “fit” means that parents have accommodated to the child’s temperamental attributes, and this contributes to positive personality growth and better adjustment.
Grandiosity: Inflated self-esteem or an exaggerated sense of self-importance and self-worth (e.g., believing one has special powers or superior abilities).
Gray matter: Composes the bark or the cortex of the cerebrum and consists of the cell bodies of the neurons (see also white matter).
Group cohesion: The solidarity or unity of a group resulting from the development of strong and mutual interpersonal bonds among members and group-level forces that unify the group, such as shared commitment to group goals.
Group polarization: The tendency for members of a deliberating group to move to a more extreme position, with the direction of the shift determined by the majority or average of the members’ predeliberation preferences.
Groupthink: A set of negative group-level processes, including illusions of invulnerability, self-censorship, and pressures to conform, that occur when highly cohesive groups seek concurrence when making a decision.
Gustation: Ability to process gustatory stimuli. Also called taste.
Gyrus: (plural form, gyri) A bulge that is raised between or among fissures of the convoluted brain.
Habit: Instrumental behavior that occurs automatically in the presence of a stimulus and is no longer influenced by the animal’s knowledge of the value of the reinforcer. Insensitive to the reinforcer devaluation effect.
HEXACO model: The HEXACO model is an alternative to the Five-Factor Model. The HEXACO model includes six traits, five of which are variants of the traits included in the Big Five (Emotionality [E], Extraversion [X], Agreeableness [A], Conscientiousness [C], and Openness [O]). The sixth factor, Honesty-Humility [H], is unique to this model.
High-stakes testing: Settings in which test scores are used to make important decisions about individuals. For example, test scores may be used to determine which individuals are admitted into a college or graduate school, or who should be hired for a job. Tests also are used in forensic settings to help determine whether a person is competent to stand trial or fits the legal definition of sanity.
Hippocampus: (plural form, hippocampi) A nucleus inside (medial) the temporal lobe implicated in learning and memory.
Homo habilis: A human ancestor, handy man, that lived two million years ago.
Homo sapiens: Modern man, the only surviving form of the genus Homo.
Honeymoon effect: The tendency for newly married individuals to rate their spouses in an unrealistically positive manner. This represents a specific manifestation of the letter of recommendation effect when applied to ratings made by current romantic partners. Moreover, it illustrates the very important role played by relationship satisfaction in ratings made by romantic partners: As marital satisfaction declines (i.e., when the “honeymoon is over”), this effect disappears.
Hypersomnia: Excessive daytime sleepiness, including difficulty staying awake or napping, or prolonged sleep episodes.
Hypothalamus: Part of the diencephalon. Regulates biological drives with pituitary gland.
Hypotheses: A logical idea that can be tested.
Hypothesis: A possible explanation that can be tested through research.
Immunocytochemistry: A method of staining tissue including the brain, using antibodies.
Implicit motives: These are goals that are important to a person, but that he/she cannot consciously express. Because the individual cannot verbalize these goals directly, they cannot be easily assessed via self-report. However, they can be measured using projective devices such as the Thematic Apperception Test (TAT).
Independent: Two characteristics or traits are separate from one another-- a person can be high on one and low on the other, or vice-versa. Some correlated traits are relatively independent in that although there is a tendency for a person high on one to also be high on the other, this is not always the case.
Independent variable: The variable the researcher manipulates and controls in an experiment.
Information processing theories: Theories that focus on describing the cognitive processes that underlie thinking at any one age and cognitive growth over time.
Inhibitory postsynaptic potentials: A hyperpolarizing postsynaptic current that causes the membrane potential to become more negative and move away from the threshold of excitation.
Instrumental conditioning: Process in which animals learn about the relationship between their behaviors and their consequences. Also known as operant conditioning.
Integrative or eclectic psychotherapy: Also called integrative psychotherapy, this term refers to approaches combining multiple orientations (e.g., CBT with psychoanalytic elements).
Integrative or eclectic psychotherapy: Also called integrative psychotherapy, this term refers to approaches combining multiple orientations (e.g., CBT with psychoanalytic elements).
Intelligence: An individual’s cognitive capability. This includes the ability to acquire, process, recall and apply information.
Interference: Other memories get in the way of retrieving a desired memory
Internal bodily or somatic cues: Physical sensations that serve as triggers for anxiety or as reminders of past traumatic events.
Interoceptive avoidance: Avoidance of situations or activities that produce sensations of physical arousal similar to those occurring during a panic attack or intense fear response.
Ion channels: Proteins that span the cell membrane, forming channels that specific ions can flow through between the intracellular and extracellular space.
Ionotropic receptor: Ion channel that opens to allow ions to permeate the cell membrane under specific conditions, such as the presence of a neurotransmitter or a specific membrane potential.
IQ: Short for “intelligence quotient.” This is a score, typically obtained from a widely used measure of intelligence that is meant to rank a person’s intellectual ability against that of others.
Just noticeable difference (JND): The smallest difference needed in order to differentiate two stimuli. (see Differential Threshold)
Lateral geniculate nucleus: (or LGN) A nucleus in the thalamus that is innervated by the optic nerves and sends signals to the visual cortex in the occipital lobe.
Lateral sulcus: The major fissure that delineates the temporal lobe below the frontal and the parietal lobes.
Law of effect: The idea that instrumental or operant responses are influenced by their effects. Responses that are followed by a pleasant state of affairs will be strengthened and those that are followed by discomfort will be weakened. Nowadays, the term refers to the idea that operant or instrumental behaviors are lawfully controlled by their consequences.
Lesion studies: A surgical method in which a part of the animal brain is removed to study its effects on behavior or function.
Letter of recommendation effect: The general tendency for informants in personality studies to rate others in an unrealistically positive manner. This tendency is due a pervasive bias in personality assessment: In the large majority of published studies, informants are individuals who like the person they are rating (e.g., they often are friends or family members) and, therefore, are motivated to depict them in a socially desirable way. The term reflects a similar tendency for academic letters of recommendation to be overly positive and to present the referent in an unrealistically desirable manner.
Levels of analysis: Complementary views for analyzing and understanding a phenomenon.
Lexical hypothesis: The lexical hypothesis is the idea that the most important differences between people will be encoded in the language that we use to describe people. Therefore, if we want to know which personality traits are most important, we can look to the language that people use to describe themselves and others.
Light adaptation: Adjustment of eye to high levels of light.
Limbic system: A loosely defined network of nuclei in the brain involved with learning and emotion.
Longitudinal study: A study that follows the same group of individuals over time.
Magnetic resonance imaging: Or MRI is a brain imaging noninvasive technique that uses magnetic energy to generate brain images (also see fMRI).
Magnification factor: Cortical space projected by an area of sensory input (e.g., mm of cortex per degree of visual field).
Mechanoreceptors: Mechanical sensory receptors in the skin that response to tactile stimulation.
Medial temporal lobes: Inner region of the temporal lobes that includes the hippocampus.
Medulla oblongata: An area just above the spinal cord that processes breathing, digestion, heart and blood vessel function, swallowing, and sneezing.
Memory traces: A term indicating the change in the nervous system representing an event.
Mindfulness: A process that reflects a nonjudgmental, yet attentive, mental state.
Mindfulness-based therapy: A form of psychotherapy grounded in mindfulness theory and practice, often involving meditation, yoga, body scan, and other features of mindfulness exercises.
Misinformation effect: When erroneous information occurring after an event is remembered as having been part of the original event.
Mnemonic devices: A strategy for remembering large amounts of information, usually involving imaging events occurring on a journey or with some other set of memorized cues.
Multimodal perception: The effects that concurrent stimulation in more than one sensory modality has on the perception of events and objects in the world.
Myelin sheath: Substance around the axon of a neuron that serves as insulation to allow the action potential to conduct rapidly toward the terminal buttons.
Nature: The genes that children bring with them to life and that influence all aspects of their development.
Need to belong: A strong natural impulse in humans to form social connections and to be accepted by others.
Neural crest: A set of primordial neurons that migrate outside the neural tube and give rise to sensory and autonomic neurons in the peripheral nervous system.
Neural induction: A process that causes the formation of the neural tube.
Neuroblasts: Brain progenitor cells that asymmetrically divide into other neuroblasts or nerve cells.
Neuroepithelium: The lining of the neural tube.
Neuropsychoanalysis: An integrative, interdisciplinary domain of inquiry seeking to integrate psychoanalytic and neuropsychological ideas and findings to enhance both areas of inquiry (you can learn more by visiting the webpage of the International Neuropsychoanalysis Society at http://www.neuropsa.org.uk/).
Neuroticism: A personality trait that reflects the tendency to be interpersonally sensitive and the tendency to experience negative emotions like anxiety, fear, sadness, and anger.
Neurotransmitters: Chemical substance released by the presynaptic terminal button that acts on the postsynaptic cell.
Nociception: Our ability to sense pain.
Norm: Assessments are given to a representative sample of a population to determine the range of scores for that population. These “norms” are then used to place an individual who takes that assessment on a range of scores in which he or she is compared to the population at large.
Nucleus: Collection of nerve cells found in the brain which typically serve a specific function.
Numerical magnitudes: The sizes of numbers.
Nurture: The environments, starting with the womb, that influence all aspects of children’s development.
Obedience: Responding to an order or command from a person in a position of authority.
Object permanence task: The Piagetian task in which infants below about 9 months of age fail to search for an object that is removed from their sight and, if not allowed to search immediately for the object, act as if they do not know that it continues to exist.
Object relations theory: A modern offshoot of the psychodynamic perspective, this theory contends that personality can be understood as reflecting mental images of significant figures (especially the parents) that we form early in life in response to interactions taking place within the family; these mental images serve as templates (or “scripts”) for later interpersonal relationships.
Observational learning: Learning by observing the behavior of others.
Observational learning: Learning by observing the behavior of others.
Obsessive-compulsive disorder (OCD): A disorder characterized by the desire to engage in certain behaviors excessively or compulsively in hopes of reducing anxiety. Behaviors include things such as cleaning, repeatedly opening and closing doors, hoarding, and obsessing over certain thoughts.
Occipital lobe: The back part of the cerebrum, which houses the visual areas.
Odorants: Chemicals transduced by olfactory receptors.
Olfaction: Ability to process olfactory stimuli. Also called smell.
Olfactory epithelium: Organ containing olfactory receptors.
Openness to Experience: A personality trait that reflects a person’s tendency to seek out and to appreciate new things, including thoughts, feelings, values, and experiences.
Operant: A behavior that is controlled by its consequences. The simplest example is the rat’s lever-pressing, which is controlled by the presentation of the reinforcer.
Operant conditioning: See instrumental conditioning.
Operational definitions: How researchers specifically measure a concept.
Opponent-process theory: Theory proposing color vision as influenced by cells responsive to pairs of colors.
Ossicles: A collection of three small bones in the middle ear that vibrate against the tympanic membrane.
Ostracism: Excluding one or more individuals from a group by reducing or eliminating contact with the person, usually by ignoring, shunning, or explicitly banishing them.
Panic disorder (PD): A condition marked by regular strong panic attacks, and which may include significant levels of worry about future attacks.
Parasympathetic nervous system: A division of the autonomic nervous system that is slower than its counterpart—that is, the sympathetic nervous system—and works in opposition to it. Generally engaged in “rest and digest” functions.
Parietal lobe: An area of the cerebrum just behind the central sulcus that is engaged with somatosensory and gustatory sensation.
Participant demand: When participants behave in a way that they think the experimenter wants them to behave.
Pavlovian conditioning: See classical conditioning.
Perception: The psychological process of interpreting sensory information.
Personality: Enduring predispositions that characterize a person, such as styles of thought, feelings and behavior.
Personality traits: Enduring dispositions in behavior that show differences across individuals, and which tend to characterize the person across varying types of situations.
Person-centered therapy: A therapeutic approach focused on creating a supportive environment for self-discovery.
Person-situation debate: The person-situation debate is a historical debate about the relative power of personality traits as compared to situational influences on behavior. The situationist critique, which started the person-situation debate, suggested that people overestimate the extent to which personality traits are consistent across situations.
Phantom limb: The perception that a missing limb still exists.
Phantom limb pain: Pain in a limb that no longer exists.
Phonemic awareness: Awareness of the component sounds within words.
Piaget’s theory: Theory that development occurs through a sequence of discontinuous stages: the sensorimotor, preoperational, concrete operational, and formal operational stages.
Pinna: Outermost portion of the ear.
Placebo effect: When receiving special treatment or something new affects human behavior.
Pons: A bridge that connects the cerebral cortex with the medulla, and reciprocally transfers information back and forth between the brain and the spinal cord.
Positron Emission Tomography: (or PET) An invasive procedure that captures brain images with positron emissions from the brain after the individual has been injected with radio-labeled isotopes.
Posttraumatic stress disorder (PTSD): A sense of intense fear, triggered by memories of a past traumatic event, that another traumatic event might occur. PTSD may include feelings of isolation and emotional numbing.
Prediction error: When the outcome of a conditioning trial is different from that which is predicted by the conditioned stimuli that are present on the trial (i.e., when the US is surprising). Prediction error is necessary to create Pavlovian conditioning (and associative learning generally). As learning occurs over repeated conditioning trials, the conditioned stimulus increasingly predicts the unconditioned stimulus, and prediction error declines. Conditioning works to correct or reduce prediction error.
Prejudice: An evaluation or emotion toward people based merely on their group membership.
Preoperational reasoning stage: Period within Piagetian theory from age 2 to 7 years, in which children can represent objects through drawing and language but cannot solve logical reasoning problems, such as the conservation problems.
Preparedness: The idea that an organism’s evolutionary history can make it easy to learn a particular association. Because of preparedness, you are more likely to associate the taste of tequila, and not the circumstances surrounding drinking it, with getting sick. Similarly, humans are more likely to associate images of spiders and snakes than flowers and mushrooms with aversive outcomes like shocks.
Primacy of the Unconscious: The hypothesis—supported by contemporary empirical research—that the vast majority of mental activity takes place outside conscious awareness.
Primary auditory cortex: Area of the cortex involved in processing auditory stimuli.
Primary Motor Cortex: A strip of cortex just in front of the central sulcus that is involved with motor control.
Primary somatosensory cortex: Area of the cortex involved in processing somatosensory stimuli.
Primary Somatosensory Cortex: A strip of cerebral tissue just behind the central sulcus engaged in sensory reception of bodily sensations.
Primary visual cortex: Area of the cortex involved in processing visual stimuli.
Principle of inverse effectiveness: The finding that, in general, for a multimodal stimulus, if the response to each unimodal component (on its own) is weak, then the opportunity for multisensory enhancement is very large. However, if one component—by itself—is sufficient to evoke a strong response, then the effect on the response gained by simultaneously processing the other components of the stimulus will be relatively small.
Projective hypothesis: The theory that when people are confronted with ambiguous stimuli (that is, stimuli that can be interpreted in more than one way), their responses will be influenced by their unconscious thoughts, needs, wishes, and impulses. This, in turn, is based on the Freudian notion of projection, which is the idea that people attribute their own undesirable/unacceptable characteristics to other people or objects.
Psychic causality: The assumption that nothing in mental life happens by chance—that there is no such thing as a “random” thought or feeling.
Psychoanalytic therapy: Sigmund Freud’s therapeutic approach focusing on resolving unconscious conflicts.
Psychodynamic therapy: Treatment applying psychoanalytic principles in a briefer, more individualized format.
Psychological vulnerabilities: Influences that our early experiences have on how we view the world.
Psychomotor agitation: Increased motor activity associated with restlessness, including physical actions (e.g., fidgeting, pacing, feet tapping, handwringing).
Psychomotor retardation: A slowing of physical activities in which routine activities (e.g., eating, brushing teeth) are performed in an unusually slow manner.
Psychosexual stage model: Probably the most controversial aspect of psychodynamic theory, the psychosexual stage model contends that early in life we progress through a sequence of developmental stages (oral, anal, Oedipal, latency, and genital), each with its own unique mode of sexual gratification.
Punisher: A stimulus that decreases the strength of an operant behavior when it is made a consequence of the behavior.
Qualitative changes: Large, fundamental change, as when a caterpillar changes into a butterfly; stage theories such as Piaget’s posit that each stage reflects qualitative change relative to previous stages.
Quantitative changes: Gradual, incremental change, as in the growth of a pine tree’s girth.
Quantitative law of effect: A mathematical rule that states that the effectiveness of a reinforcer at strengthening an operant response depends on the amount of reinforcement earned for all alternative behaviors. A reinforcer is less effective if there is a lot of reinforcement in the environment for other behaviors.
Quasi-experimental design: An experiment that does not require random assignment to conditions.
Random assignment: Assigning participants to receive different conditions of an experiment by chance.
Reappraisal, or Cognitive restructuring: The process of identifying, evaluating, and changing maladaptive thoughts in psychotherapy.
Reciprocity: The act of exchanging goods or services. By giving a person a gift, the principle of reciprocity can be used to influence others; they then feel obligated to give back.
Recoding: The ubiquitous process during learning of taking information in one form and converting it to another form, usually one more easily remembered.
Reference group effect: The tendency of people to base their self-concept on comparisons with others. For example, if your friends tend to be very smart and successful, you may come to see yourself as less intelligent and successful than you actually are. Informants also are prone to these types of effects. For instance, the sibling contrast effect refers to the tendency of parents to exaggerate the true extent of differences between their children.
Reinforced response: Following the process of operant conditioning, the strengthening of a response following either the delivery of a desired consequence (positive reinforcement) or escape from an aversive consequence.
Reinforcer: Any consequence of a behavior that strengthens the behavior or increases the likelihood that it will be performed it again.
Reinforcer devaluation effect: The finding that an animal will stop performing an instrumental response that once led to a reinforcer if the reinforcer is separately made aversive or undesirable.
Reliablility: The consistency of test scores across repeated assessments. For example, test-retest reliability examines the extent to which scores change over time.
Renewal effect: Recovery of an extinguished response that occurs when the context is changed after extinction. Especially strong when the change of context involves return to the context in which conditioning originally occurred. Can occur after extinction in either classical or instrumental conditioning.
Research confederate: A person working with a researcher, posing as a research participant or as a bystander.
Research participant: A person being studied as part of a research program.
Resting membrane potential: The voltage inside the cell relative to the voltage outside the cell while the cell is a rest (approximately -70 mV).
Retina: Cell layer in the back of the eye containing photoreceptors.
Retrieval: The process of accessing stored information.
Retrieval: Process by which information is accessed from memory and utilized.
Retroactive interference: The phenomenon whereby events that occur after some particular event of interest will usually cause forgetting of the original event.
Retrograde amnesia: Inability to retrieve memories for facts and events acquired before the onset of amnesia.
Rods: Photoreceptors of the retina sensitive to low levels of light. Located around the fovea.
Rostrocaudal: A front-back plane used to identify anatomical structures in the body and the brain.
SAD performance only: Social anxiety disorder which is limited to certain situations that the sufferer perceives as requiring some type of performance.
Schema: A mental representation or set of beliefs about something.
Security of attachment: An infant’s confidence in the sensitivity and responsiveness of a caregiver, especially when he or she is needed. Infants can be securely attached or insecurely attached.
Self-enhancement bias: The tendency for people to see and/or present themselves in an overly favorable way. This tendency can take two basic forms: defensiveness (when individuals actually believe they are better than they really are) and impression management (when people intentionally distort their responses to try to convince others that they are better than they really are). Informants also can show enhancement biases. The general form of this bias has been called the letter-of-recommendation effect, which is the tendency of informants who like the person they are rating (e.g., friends, relatives, romantic partners) to describe them in an overly favorable way. In the case of newlyweds, this tendency has been termed the honeymoon effect.
Semantic memory: The more or less permanent store of knowledge that people have.
Sensation: The physical processing of environmental stimuli by the sense organs.
Sensorimotor stage: Period within Piagetian theory from birth to age 2 years, during which children come to represent the enduring reality of objects.
Sensory adaptation: Decrease in sensitivity of a receptor to a stimulus after constant stimulation.
Shape theory of olfaction: Theory proposing that odorants of different size and shape correspond to different smells.
Shared mental model: Knowledge, expectations, conceptualizations, and other cognitive representations that members of a group have in common pertaining to the group and its members, tasks, procedures, and resources.
Sibling contrast effect: The tendency of parents to use their perceptions of all of their children as a frame of reference for rating the characteristics of each of them. For example, suppose that a mother has three children; two of these children are very sociable and outgoing, whereas the third is relatively average in sociability. Because of operation of this effect, the mother will rate this third child as less sociable and outgoing than he/she actually is. More generally, this effect causes parents to exaggerate the true extent of differences between their children. This effect represents a specific manifestation of the more general reference group effect when applied to ratings made by parents.
Signal detection: Method for studying the ability to correctly identify sensory stimuli.
Social anxiety disorder (SAD): A condition marked by acute fear of social situations which lead to worry and diminished day to day functioning.
Social attribution: The way a person explains the motives or behaviors of others.
Social cognition: The way people process and apply information about others.
Social comparison: The process of contrasting one’s personal qualities and outcomes, including beliefs, attitudes, values, abilities, accomplishments, and experiences, to those of other people.
Social facilitation: Improvement in task performance that occurs when people work in the presence of other people.
Social identity theory: A theoretical analysis of group processes and intergroup relations that assumes groups influence their members’ self-concepts and self-esteem, particularly when individuals categorize themselves as group members and identify with the group.
Social influence: When one person causes a change in attitude or behavior in another person, whether intentionally or unintentionally.
Social Learning Theory: The theory that people can learn new responses and behaviors by observing the behavior of others.
Social loafing: The reduction of individual effort exerted when people work in groups compared with when they work alone.
Social models: Authorities that are the targets for observation and who model behaviors.
Social psychology: The branch of psychological science that is mainly concerned with understanding how the presence of others affects our thoughts, feelings, and behaviors.
Social referencing: The process by which one individual consults another’s emotional expressions to determine how to evaluate and respond to circumstances that are ambiguous or uncertain.
Social zeitgeber: Zeitgeber is German for “time giver.” Social zeitgebers are environmental cues, such as meal times and interactions with other people, that entrain biological rhythms and thus sleep-wake cycle regularity.
Sociocultural theories: Theory founded in large part by Lev Vygotsky that emphasizes how other people and the attitudes, values, and beliefs of the surrounding culture influence children’s development.
Socioeconomic status (SES): A person’s economic and social position based on income, education, and occupation.
Sociometer model: A conceptual analysis of self-evaluation processes that theorizes self-esteem functions to psychologically monitor of one’s degree of inclusion and exclusion in social groups.
Sodium-potassium pump: An ion channel that uses the neuron’s energy (adenosine triphosphate, ATP) to pump three Na+ ions outside the cell in exchange for bringing two K+ ions inside the cell.
Soma: Cell body of a neuron that contains the nucleus and genetic information, and directs protein synthesis.
Somatic nervous system: A part of the peripheral nervous system that uses cranial and spinal nerves in volitional actions.
Somatosensation: Ability to sense touch, pain and temperature.
Somatotopic map: Organization of the primary somatosensory cortex maintaining a representation of the arrangement of the body.
Sound waves: Changes in air pressure. The physical stimulus for audition.
Specific vulnerabilities: How our experiences lead us to focus and channel our anxiety.
Spina bifida: A developmental disease of the spinal cord, where the neural tube does not close caudally.
Spines: Protrusions on the dendrite of a neuron that form synapses with terminal buttons of the presynaptic axon.
Spontaneous recovery: Recovery of an extinguished response that occurs with the passage of time after extinction. Can occur after extinction in either classical or instrumental conditioning.
Standardize: Assessments that are given in the exact same manner to all people . With regards to intelligence tests standardized scores are individual scores that are computed to be referenced against normative scores for a population (see “norm”).
Stereotype threat: The phenomenon in which people are concerned that they will conform to a stereotype or that their performance does conform to that stereotype, especially in instances in which the stereotype is brought to their conscious awareness.
Stereotyping: A mental process of using information shortcuts about a group to effectively navigate social situations or make decisions.
Stigmatized group: A group that suffers from social disapproval based on some characteristic that sets them apart from the majority.
Stimulus control: When an operant behavior is controlled by a stimulus that precedes it.
Storage: The stage in the learning/memory process that bridges encoding and retrieval; the persistence of memory over time.
Structural model: Developed to complement and extend the topographic model, the structural model of the mind posits the existence of three interacting mental structures called the id, ego, and superego.
Suicidal ideation: Recurring thoughts about suicide, including considering or planning for suicide, or preoccupation with suicide.
Sulcus: (plural form, sulci) The crevices or fissures formed by convolutions in the brain.
Superadditive effect of multisensory integration: The finding that responses to multimodal stimuli are typically greater than the sum of the independent responses to each unimodal component if it were presented on its own.
Sympathetic nervous system: A division of the autonomic nervous system, that is faster than its counterpart that is the parasympathetic nervous system and works in opposition to it. Generally engaged in “fight or flight” functions.
Synapse: Junction between the presynaptic terminal button of one neuron and the dendrite, axon, or soma of another postsynaptic neuron.
Synaptic gap: Also known as the synaptic cleft; the small space between the presynaptic terminal button and the postsynaptic dendritic spine, axon, or soma.
Synaptic vesicles: Groups of neurotransmitters packaged together and located within the terminal button.
Systematic observation: The careful observation of the natural world with the aim of better understanding it. Observations provide the basic data that allow scientists to track, tally, or otherwise organize information about the natural world.
Tastants: Chemicals transduced by taste receptor cells.
Taste aversion learning: The phenomenon in which a taste is paired with sickness, and this causes the organism to reject—and dislike—that taste in the future.
Taste receptor cells: Receptors that transduce gustatory information.
Teamwork: The process by which members of the team combine their knowledge, skills, abilities, and other resources through a coordinated series of actions to produce an outcome.
Temperament: Early emerging differences in reactivity and self-regulation, which constitutes a foundation for personality development.
Temporal lobe: An area of the cerebrum that lies below the lateral sulcus; it contains auditory and olfactory (smell) projection regions.
Temporally graded retrograde amnesia: Inability to retrieve memories from just prior to the onset of amnesia with intact memory for more remote events.
Terminal button: The part of the end of the axon that form synapses with postsynaptic dendrite, axon, or soma.
Thalamus: A part of the diencephalon that works as a gateway for incoming and outgoing information.
Theories: Groups of closely related phenomena or observations.
Theory of mind: Children’s growing understanding of the mental states that affect people’s behavior.
Thought-action fusion: The tendency to overestimate the relationship between a thought and an action, such that one mistakenly believes a “bad” thought is the equivalent of a “bad” action.
Threshold of excitation: Specific membrane potential that the neuron must reach to initiate an action potential.
Top-down processing: Experience influencing the perception of stimuli.
Topographic model: Freud’s first model of the mind, which contended that the mind could be divided into three regions: conscious, preconscious, and unconscious. (The “topographic” comes from the fact that topography is the study of maps.)
Transduction: The conversion of one form of energy into another.
Transduction: A process in which physical energy converts into neural energy.
Trichromatic theory: Theory proposing color vision as influenced by three different cones responding preferentially to red, green and blue.
Tympanic membrane: Thin, stretched membrane in the middle ear that vibrates in response to sound. Also called the eardrum.
Unconditional positive regard: In person-centered therapy, an attitude of warmth, empathy and acceptance adopted by the therapist in order to foster feelings of inherent worth in the patient.
Unconditioned response (UR): In classical conditioning, an innate response that is elicited by a stimulus before (or in the absence of) conditioning.
Unconditioned stimulus (US): In classical conditioning, the stimulus that elicits the response before conditioning occurs.
Validity: Evidence related to the interpretation and use of test scores. A particularly important type of evidence is criterion validity, which involves the ability of a test to predict theoretically relevant outcomes. For example, a presumed measure of conscientiousness should be related to academic achievement (such as overall grade point average).
Ventral pathway: Pathway of visual processing. The “what” pathway.
Vestibular system: Parts of the inner ear involved in balance.
Vicarious reinforcement: Learning that occurs by observing the reinforcement or punishment of another person.
Weber’s law: States that just noticeable difference is proportional to the magnitude of the initial stimulus.
Wernicke’s area: A language area in the temporal lobe where linguistic information is comprehended (Also see Broca’s area).
White matter: Regions of the nervous system that represent the axons of the nerve cells; whitish in color because of myelination of the nerve cells.
Working memory: Short transitory memory processed in the hippocampus.