Vocabulary

Abducens nucleus: A group of excitatory motor neurons in the medial brainstem that send projections through the VIth cranial nerve to control the ipsilateral lateral rectus muscle. In addition, abducens interneurons send an excitatory projection across the midline to a subdivision of cells in the ipsilateral oculomotor nucleus, which project through the IIIrd cranial nerve to innervate the ipsilateral medial rectus muscle.
Ablation: Surgical removal of brain tissue.
Acetylcholine: An organic compound neurotransmitter consisting of acetic acid and choline. Depending upon the receptor type, acetycholine can have excitatory, inhibitory, or modulatory effects.
Action potential: A transient all-or-nothing electrical current that is conducted down the axon when the membrane potential reaches the threshold of excitation.
Adaptation: The fact that after people first react to good or bad events, sometimes in a strong way, their feelings and reactions tend to dampen down over time and they return toward their original level of subjective well-being.
Adaptations: Evolved solutions to problems that historically contributed to reproductive success.
Adoption study: A behavior genetic research method that involves comparison of adopted children to their adoptive and biological parents.
Affect: An emotional process; includes moods, subjective feelings, and discrete emotions.
Affective forecasting: Predicting how one will feel in the future after some event or decision.
Afferent nerve fibers: Single neurons that innervate the receptor hair cells and carry vestibular signals to the brain as part of the vestibulocochlear nerve (cranial nerve VIII).
Afferent nerves: Nerves that carry messages to the brain or spinal cord.
A-fibers: Fast-conducting sensory nerves with myelinated axons. Larger diameter and thicker myelin sheaths increases conduction speed. Aβ-fibers conduct touch signals from low-threshold mechanoreceptors with a velocity of 80 m/s and a diameter of 10 μm; Aδ-fibers have a diameter of 2.5 μm and conduct cold, noxious, and thermal signals at 12 m/s. The third and fastest conducting A-fiber is the Aα, which conducts proprioceptive information with a velocity of 120 m/s and a diameter of 20 μm.
Age identity: How old or young people feel compared to their chronological age; after early adulthood, most people feel younger than their chronological age.
Agender: An individual who may have no gender or may describe themselves as having a neutral gender.
Aggression: Any behavior intended to harm another person who does not want to be harmed.
Agnosias: Due to damage of Wernicke’s area. An inability to recognize objects, words, or faces.
Agonists: A drug that increases or enhances a neurotransmitter’s effect.
Allodynia: Pain due to a stimulus that does not normally provoke pain, e.g., when a light, stroking touch feels painful.
Alogia: A reduction in the amount of speech and/or increased pausing before the initiation of speech.
Ambivalent sexism: A concept of gender attitudes that encompasses both positive and negative qualities.
Ambulatory assessment: An overarching term to describe methodologies that assess the behavior, physiology, experience, and environments of humans in naturalistic settings.
Amygdala: Two almond-shaped structures located in the medial temporal lobes of the brain.
Amygdala: A region located deep within the brain in the medial area (toward the center) of the temporal lobes (parallel to the ears). If you could draw a line through your eye sloping toward the back of your head and another line between your two ears, the amygdala would be located at the intersection of these lines. The amygdala is involved in detecting relevant stimuli in our environment and has been implicated in emotional responses.
Analgesia: Pain relief.
Anchoring: The bias to be affected by an initial anchor, even if the anchor is arbitrary, and to insufficiently adjust our judgments away from that anchor.
Anhedonia/amotivation: A reduction in the drive or ability to take the steps or engage in actions necessary to obtain the potentially positive outcome.
Animism: The belief that everyone and everything had a “soul” and that mental illness was due to animistic causes, for example, evil spirits controlling an individual and his/her behavior.
Anomalous face overgeneralization hypothesis: Proposes that the attractiveness halo effect is a by-product of reactions to low fitness. People overgeneralize the adaptive tendency to use low attractiveness as an indicator of negative traits, like low health or intelligence, and mistakenly use higher-than-average attractiveness as an indicator of high health or intelligence.
Antagonist: A drug that blocks a neurotransmitter’s effect.
Anterograde amnesia: Inability to form new memories for facts and events after the onset of amnesia.
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.
Aspartate: An excitatory amino acid neurotransmitter that is widely used by vestibular receptors, afferents, and many neurons in the brain.
Asylum: A place of refuge or safety established to confine and care for the mentally ill; forerunners of the mental hospital or psychiatric facility.
Attitude: A psychological tendency that is expressed by evaluating a particular entity with some degree of favor or disfavor.
Attractiveness halo effect: The tendency to associate attractiveness with a variety of positive traits, such as being more sociable, intelligent, competent, and healthy.
Audience design: Constructing utterances to suit the audience’s knowledge.
Autobiographical memory: Memory for the events of one’s life.
Autobiographical narratives: A qualitative research method used to understand characteristics and life themes that an individual considers to uniquely distinguish him- or herself from others.
Automatic: A behavior or process has one or more of the following features: unintentional, uncontrollable, occurring outside of conscious awareness, and cognitively efficient.
Automatic empathy: A social perceiver unwittingly taking on the internal state of another person, usually because of mimicking the person’s expressive behavior and thereby feeling the expressed emotion.
Automatic process: When a thought, feeling, or behavior occurs with little or no mental effort. Typically, automatic processes are described as involuntary or spontaneous, often resulting from a great deal of practice or repetition.
Autonomic nervous system: A part of the peripheral nervous system that connects to glands and smooth muscles. Consists of sympathetic and parasympathetic divisions.
Availability heuristic: The tendency to judge the frequency or likelihood of an event by the ease with which relevant instances come to mind.
Availability heuristic: A heuristic in which the frequency or likelihood of an event is evaluated based on how easily instances of it come to mind.
Average life expectancy: Mean number of years that 50% of people in a specific birth cohort are expected to survive. This is typically calculated from birth but is also sometimes re-calculated for people who have already reached a particular age (e.g., 65).
Awareness: A conscious experience or the capability of having conscious experiences, which is distinct from self-awareness, the conscious understanding of one’s own existence and individuality.
Axial plane: See “horizontal plane.”
Axon: Part of the neuron that extends off the soma, splitting several times to connect with other neurons; main output of the neuron.
Balancing between goals: Shifting between a focal goal and other goals or temptations by putting less effort into the focal goal—usually with the intention of coming back to the focal goal at a later point in time.
Basal ganglia: Subcortical structures of the cerebral hemispheres involved in voluntary movement.
Basic-level category: The neutral, preferred category for a given object, at an intermediate level of specificity.
Behavioral genetics: The empirical science of how genes and environments combine to generate behavior.
Behaviorism: The study of behavior.
Benevolent sexism: The “positive” element of ambivalent sexism, which recognizes that women are perceived as needing to be protected, supported, and adored by men.
Biases: The systematic and predictable mistakes that influence the judgment of even very talented human beings.
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).
Bigender: An individual who identifies as two genders.
Binary: The idea that gender has two separate and distinct categories (male and female) and that a person must be either one or the other.
Binocular advantage: Benefits from having two eyes as opposed to a single eye.
Biopsychosocial model: A model in which the interaction of biological, psychological, and sociocultural factors is seen as influencing the development of the individual.
Blood-oxygen-level-dependent (BOLD): The signal typically measured in fMRI that results from changes in the ratio of oxygenated hemoglobin to deoxygenated hemoglobin in the blood.
“Bottom-up” or external causes of happiness: Situational factors outside the person that influence his or her subjective well-being, such as good and bad events and circumstances such as health and wealth.
Bouncing balls illusion: The tendency to perceive two circles as bouncing off each other if the moment of their contact is accompanied by an auditory stimulus.
Bounded awareness: The systematic ways in which we fail to notice obvious and important information that is available to us.
Bounded ethicality: The systematic ways in which our ethics are limited in ways we are not even aware of ourselves.
Bounded rationality: Model of human behavior that suggests that humans try to make rational decisions but are bounded due to cognitive limitations.
Bounded self-interest: The systematic and predictable ways in which we care about the outcomes of others.
Bounded willpower: The tendency to place greater weight on present concerns rather than future concerns.
Brain stem: The “trunk” of the brain comprised of the medulla, pons, midbrain, and diencephalon.
Broca’s area: An area in the frontal lobe of the left hemisphere. Implicated in language production.
Callosotomy: Surgical procedure in which the corpus callosum is severed (used to control severe epilepsy).
Case study: A thorough study of a patient (or a few patients) with naturally occurring lesions.
Catatonia: Behaviors that seem to reflect a reduction in responsiveness to the external environment. This can include holding unusual postures for long periods of time, failing to respond to verbal or motor prompts from another person, or excessive and seemingly purposeless motor activity.
Category: A set of entities that are equivalent in some way. Usually the items are similar to one another.
Catharsis: Greek term that means to cleanse or purge. Applied to aggression, catharsis is the belief that acting aggressively or even viewing aggression purges angry feelings and aggressive impulses into harmless channels.
Cathartic method: A therapeutic procedure introduced by Breuer and developed further by Freud in the late 19th century whereby a patient gains insight and emotional relief from recalling and reliving traumatic events.
Cause-and-effect: Related to whether we say one variable is causing changes in the other variable, versus other variables that may be related to these two variables.
Cell membrane: A bi-lipid layer of molecules that separates the cell from the surrounding extracellular fluid.
Central nervous system: The part of the nervous system that consists of the brain and spinal cord.
Central sulcus: The major fissure that divides the frontal and the parietal lobes.
Cerebellum: The distinctive structure at the back of the brain, Latin for “small brain.”
Cerebellum: A nervous system structure behind and below the cerebrum. Controls motor movement coordination, balance, equilibrium, and muscle tone.
Cerebral cortex: The outermost gray matter of the cerebrum; the distinctive convoluti characteristic of the mammalian brain.
Cerebral hemispheres: The cerebral cortex, underlying white matter, and subcortical structures.
Cerebrum: Usually refers to the cerebral cortex and associated white matter, but in some texts includes the subcortical structures.
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.
C-fibers: C-fibers: Slow-conducting unmyelinated thin sensory afferents with a diameter of 1 μm and a conduction velocity of approximately 1 m/s. C-pain fibers convey noxious, thermal, and heat signals; C-tactile fibers convey gentle touch, light stroking.
Chameleon effect: The tendency for individuals to nonconsciously mimic the postures, mannerisms, facial expressions, and other behaviors of one’s interaction partners.
Chronic pain: Persistent or recurrent pain, beyond usual course of acute illness or injury; sometimes present without observable tissue damage or clear cause.
Chunk: The process of grouping information together using our knowledge.
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.
Cisgender: A term used to describe individuals whose gender matches their biological sex.
Classical conditioning: Describes stimulus-stimulus associative learning.
Cochlea: Snail-shell-shaped organ that transduces mechanical vibrations into neural signals.
Cognitive psychology: The study of mental processes.
Cohort: Group of people typically born in the same year or historical period, who share common experiences over time; sometimes called a generation (e.g., Baby Boom Generation).
Commitment: The sense that a goal is both valuable and attainable
Common ground: Information that is shared by people who engage in a conversation.
Compensatory reflexes: A stabilizing motor reflex that occurs in response to a perceived movement, such as the vestibuloocular reflex, or the postural responses that occur during running or skiing.
Computerized axial tomography: A noninvasive brain-scanning procedure that uses X-ray absorption around the head.
Concept: The mental representation of a category.
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.
Cones: Photoreceptors that operate in lighted environments and can encode fine visual details. There are three different kinds (S or blue, M or green and L or red) that are each sensitive to slightly different types of light. Combined, these three types of cones allow you to have color vision.
Confidence interval: An interval of plausible values for a population parameter; the interval of values within the margin of error of a statistic.
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.
Conscious experience: The first-person perspective of a mental event, such as feeling some sensory input, a memory, an idea, an emotion, a mood, or a continuous temporal sequence of happenings.
Conscious goal activation: When a person is fully aware of contextual influences and resulting goal-directed behavior.
Consciousness: Awareness of ourselves and our environment.
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: Process by which a memory trace is stabilized and transformed into a more durable form.
Consolidation: The process occurring after encoding that is believed to stabilize memory traces.
Contemplative science: A research area concerned with understanding how contemplative practices such as meditation can affect individuals, including changes in their behavior, their emotional reactivity, their cognitive abilities, and their brains. Contemplative science also seeks insights into conscious experience that can be gained from first-person observations by individuals who have gained extraordinary expertise in introspection.
Continuous development: Ways in which development occurs in a gradual incremental manner, rather than through sudden jumps.
Contralateral: Literally “opposite side”; used to refer to the fact that the two hemispheres of the brain process sensory information and motor commands for the opposite side of the body (e.g., the left hemisphere controls the right side of the body).
Contrast: Relative difference in the amount and type of light coming from two nearby locations.
Contrast gain: Process where the sensitivity of your visual system can be tuned to be most sensitive to the levels of contrast that are most prevalent in the environment.
Converging evidence: Similar findings reported from multiple studies using different methods.
Convoy Model of Social Relations: Theory that proposes that the frequency, types, and reciprocity of social exchanges change with age. These social exchanges impact the health and well-being of the givers and receivers in the convoy.
Coronal plane: A slice that runs from head to foot; brain slices in this plane are similar to slices of a loaf of bread, with the eyes being the front of the loaf.
Correlation: Measures the association between two variables, or how they go together.
Cortisol: A hormone made by the adrenal glands, within the cortex. Cortisol helps the body maintain blood pressure and immune function. Cortisol increases when the body is under stress.
C-pain or Aδ-fibers: C-pain fibers convey noxious, thermal, and heat signals
Crossmodal phenomena: Effects that concern the influence of the perception of one sensory modality on the perception of another.
Crossmodal receptive field: A receptive field that can be stimulated by a stimulus from more than one sensory modality.
Crossmodal stimulus: A stimulus with components in multiple sensory modalties that interact with each other.
Cross-sectional studies: Research method that provides information about age group differences; age differences are confounded with cohort differences and effects related to history and time of study.
Crowds: Adolescent peer groups characterized by shared reputations or images.
Crystallized intelligence: Type of intellectual ability that relies on the application of knowledge, experience, and learned information.
C-tactile fibers: C-tactile fibers convey gentle touch, light stroking
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.
Cultural relativism: The idea that cultural norms and values of a society can only be understood on their own terms or in their own context.
Cutaneous senses: The senses of the skin: tactile, thermal, pruritic (itchy), painful, and pleasant.
Daily Diary method: A methodology where participants complete a questionnaire about their thoughts, feelings, and behavior of the day at the end of the day.
Dark adaptation: Process that allows you to become sensitive to very small levels of light, so that you can actually see in the near-absence of light.
Day reconstruction method (DRM): A methodology where participants describe their experiences and behavior of a given day retrospectively upon a systematic reconstruction on the following day.
Decay: The fading of memories with the passage of time.
Declarative memory: Conscious memories for facts and events.
Deliberative phase: The first of the two basic stages of self-regulation in which individuals decide which of many potential goals to pursue at a given point in time.
Delusions: False beliefs that are often fixed, hard to change even in the presence of conflicting information, and often culturally influenced in their content.
Dendrite: Part of a neuron that extends away from the cell body and is the main input to the neuron.
Deoxygenated hemoglobin: Hemoglobin not carrying oxygen.
Dependent variable: The variable the researcher measures but does not manipulate in an experiment.
Depolarization: A change in a cell’s membrane potential, making the inside of the cell more positive and increasing the chance of an action potential.
Depolarized: When receptor hair cells have mechanically gated channels open, the cell increases its membrane voltage, which produces a release of neurotransmitter to excite the innervating nerve fiber.
Depth perception: The ability to actively perceive the distance from oneself of objects in the environment.
Descending pain modulatory system: A top-down pain-modulating system able to inhibit or facilitate pain. The pathway produces analgesia by the release of endogenous opioids. Several brain structures and nuclei are part of this circuit, such as the frontal lobe areas of the anterior cingulate cortex, orbitofrontal cortex, and insular cortex; and nuclei in the amygdala and the hypothalamus, which all project to a structure in the midbrain called the periaqueductal grey (PAG). The PAG then controls ascending pain transmission from the afferent pain system indirectly through the rostral ventromedial medulla (RVM) in the brainstem, which uses ON- and OFF-cells to inhibit or facilitate nociceptive signals at the spinal dorsal horn.
Descriptive norm: The perception of what most people do in a given situation.
Detection thresholds: The smallest amount of head motion that can be reliably reported by an observer.
Developmental intergroup theory: A theory that postulates that adults’ focus on gender leads children to pay attention to gender as a key source of information about themselves and others, to seek out possible gender differences, and to form rigid stereotypes based on gender.
Deviant peer contagion: The spread of problem behaviors within groups of adolescents.
Diagnostic criteria: The specific criteria used to determine whether an individual has a specific type of psychiatric disorder. Commonly used diagnostic criteria are included in the Diagnostic and Statistical Manual of Mental Disorder, 5th Edition (DSM-5) and the Internal Classification of Disorders, Version 9 (ICD-9).
Dichotic listening: An experimental task in which two messages are presented to different ears.
Dichotic listening: A task in which different audio streams are presented to each ear. Typically, people are asked to monitor one stream while ignoring the other.
Differential susceptibility: Genetic factors that make individuals more or less responsive to environmental experiences.
Diffuse optical imaging (DOI): A neuroimaging technique that infers brain activity by measuring changes in light as it is passed through the skull and surface of the brain.
Diffusion: The force on molecules to move from areas of high concentration to areas of low concentration.
Directional goals: The motivation to reach a particular outcome or judgment.
Directional tuning: The preferred direction of motion that hair cells and afferents exhibit where a peak excitatory response occurs and the least preferred direction where no response occurs. Cells are said to be “tuned” for a best and worst direction of motion, with in-between motion directions eliciting a lesser but observable response.
Discontinuous development: Discontinuous development
Disorganized behavior: Behavior or dress that is outside the norm for almost all subcultures. This would include odd dress, odd makeup (e.g., lipstick outlining a mouth for 1 inch), or unusual rituals (e.g., repetitive hand gestures).
Disorganized speech: Speech that is difficult to follow, either because answers do not clearly follow questions or because one sentence does not logically follow from another.
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.
Distribution: The pattern of variation in data.
Divided attention: The ability to flexibly allocate attentional resources between two or more concurrent tasks.
Dopamine: A neurotransmitter in the brain that is thought to play an important role in regulating the function of other neurotransmitters.
Double flash illusion: The false perception of two visual flashes when a single flash is accompanied by two auditory beeps.
Drive state: Affective experiences that motivate organisms to fulfill goals that are generally beneficial to their survival and reproduction.
Durability bias: A bias in affective forecasting in which one overestimates for how long one will feel an emotion (positive or negative) after some event.
Ecological momentary assessment: An overarching term to describe methodologies that repeatedly sample participants’ real-world experiences, behavior, and physiology in real time.
Ecological validity: The degree to which a study finding has been obtained under conditions that are typical for what happens in everyday life.
Ectoderm: The outermost layer of a developing fetus.
Efferent nerves: Nerves that carry messages from the brain to glands and organs in the periphery.
Ego-depletion: The exhaustion of physiological and/or psychological resources following the completion of effortful self-control tasks, which subsequently leads to reduction in the capacity to exert more self-control.
Electroencephalogram: A measure of electrical activity generated by the brain’s neurons.
Electroencephalography: A technique that is used to measure gross electrical activity of the brain by placing electrodes on the scalp.
Electroencephalography (EEG): A neuroimaging technique that measures electrical brain activity via multiple electrodes on the scalp.
Electronically activated recorder, or EAR: A methodology where participants wear a small, portable audio recorder that intermittently records snippets of ambient sounds around them.
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.
Empiricism: The belief that knowledge comes from experience.
Encoding: Process by which information gets into memory.
Encoding: The pact of putting information into memory.
Encoding: The initial experience of perceiving and learning events.
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.
Endophenotypes: A characteristic that reflects a genetic liability for disease and a more basic component of a complex clinical presentation. Endophenotypes are less developmentally malleable than overt behavior.
Endorphin: An endogenous morphine-like peptide that binds to the opioid receptors in the brain and body; synthesized in the body’s nervous system.
Engrams: A term indicating the change in the nervous system representing an event; also, memory trace.
Enzyme: A protein produced by a living organism that allows or helps a chemical reaction to occur.
Enzyme induction: Process through which a drug can enhance the production of an enzyme.
Episodic memory: Memory for events in a particular time and place.
Episodic memory: The ability to learn and retrieve new information or episodes in one’s life.
Error management theory (EMT): A theory of selection under conditions of uncertainty in which recurrent cost asymmetries of judgment or inference favor the evolution of adaptive cognitive biases that function to minimize the more costly errors.
Etiology: The causal description of all of the factors that contribute to the development of a disorder or illness.
Eugenics: The practice of selective breeding to promote desired traits.
Evaluative priming task: An implicit attitude task that assesses the extent to which an attitude object is associated with a positive or negative valence by measuring the time it takes a person to label an adjective as good or bad after being presented with an attitude object.
Event-related potentials: A physiological measure of large electrical change in the brain produced by sensory stimulation or motor responses.
Event-related potentials (ERP): Measures the firing of groups of neurons in the cortex. As a person views or listens to specific types of information, neuronal activity creates small electrical currents that can be recorded from non-invasive sensors placed on the scalp. ERP provides excellent information about the timing of processing, clarifying brain activity at the millisecond pace at which it unfolds.
Evolution: Change over time. Is the definition changing?
Excitatory postsynaptic potentials: A depolarizing postsynaptic current that causes the membrane potential to become more positive and move towards the threshold of excitation.
Exemplar: An example in memory that is labeled as being in a particular category.
Experience-sampling method: A methodology where participants report on their momentary thoughts, feelings, and behaviors at different points in time over the course of a day.
Experimenter expectations: When the experimenter’s expectations influence the outcome of a study.
Explicit attitude: An attitude that is consciously held and can be reported on by the person holding the attitude.
External validity: The degree to which a finding generalizes from the specific sample and context of a study to some larger population and broader settings.
Exteroception: The sense of the external world, of all stimulation originating from outside our own bodies.
Extrinsic motivation: Motivation stemming from the benefits associated with achieving a goal such as obtaining a monetary reward.
False memories: Memory for an event that never actually occurred, implanted by experimental manipulation or other means.
False-belief test: An experimental procedure that assesses whether a perceiver recognizes that another person has a false belief—a belief that contradicts reality.
Fight or flight response: The physiological response that occurs in response to a perceived threat, preparing the body for actions needed to deal with the threat.
First-person perspective: Observations made by individuals about their own conscious experiences, also known as introspection or a subjective point of view. Phenomenology refers to the description and investigation of such observations.
Flashbulb memory: A highly detailed and vivid memory of an emotionally significant event.
Flashbulb memory: Vivid personal memories of receiving the news of some momentous (and usually emotional) event.
Flat affect: A reduction in the display of emotions through facial expressions, gestures, and speech intonation.
Fluid intelligence: Type of intelligence that relies on the ability to use information processing resources to reason logically and solve novel problems.
Foils: Any member of a lineup (whether live or photograph) other than the suspect.
Folk explanations of behavior: People’s natural explanations for why somebody did something, felt something, etc. (differing substantially for unintentional and intentional behaviors).
Forebrain: A part of the nervous system that contains the cerebral hemispheres, thalamus, and hypothalamus.
Foreclosure: Individuals commit to an identity without exploration of options.
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.
Framing: The bias to be systematically affected by the way in which information is presented, while holding the objective information constant.
Frontal lobe: The front most (anterior) part of the cerebrum; anterior to the central sulcus and responsible for motor output and planning, language, judgment, and decision-making.
Frontal lobe: The most forward region (close to forehead) of the cerebral hemispheres.
Full-cycle psychology: A scientific approach whereby researchers start with an observational field study to identify an effect in the real world, follow up with laboratory experimentation to verify the effect and isolate the causal mechanisms, and return to field research to corroborate their experimental findings.
Functional capacity: The ability to engage in self-care (cook, clean, bathe), work, attend school, and/or engage in social relationships.
Functional magnetic resonance imaging: A measure of changes in the oxygenation of blood flow as areas in the brain become active.
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).
Functional magnetic resonance imaging (fMRI): Functional magnetic resonance imaging (fMRI): A neuroimaging technique that infers brain activity by measuring changes in oxygen levels in the blood.
Functional magnetic resonance imaging (fMRI): Entails the use of powerful magnets to measure the levels of oxygen within the brain that vary with changes in neural activity. That is, as the neurons in specific brain regions “work harder” when performing a specific task, they require more oxygen. By having people listen to or view social percepts in an MRI scanner, fMRI specifies the brain regions that evidence a relative increase in blood flow. In this way, fMRI provides excellent spatial information, pinpointing with millimeter accuracy, the brain regions most critical for different social processes.
Functional neuroanatomy: Classifying how regions within the nervous system relate to psychology and behavior.
Functionalism: A school of American psychology that focused on the utility of consciousness.
g or general mental ability: The general factor common to all cognitive ability measures, “a very general mental capacity that, among other things, involves the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly, and learn from experience. It is not merely book learning, a narrow academic skill, or test-taking smarts. Rather, it reflects a broader and deeper capability for comprehending our surroundings—‘catching on,’ ‘making sense of things,’ or ‘figuring out’ what to do” (Gottfredson, 1997, p. 13).
Gamma-aminobutyric acid: A major inhibitory neurotransmitter in the vestibular commissural system.
Gaze stability: A combination of eye, neck, and head responses that are all coordinated to maintain visual fixation (fovea) upon a point of interest.
Gender: The cultural, social, and psychological meanings that are associated with masculinity and femininity.
Gender constancy: The awareness that gender is constant and does not change simply by changing external attributes; develops between 3 and 6 years of age.
Gender discrimination: Differential treatment on the basis of gender.
Gender identity: A person’s psychological sense of being male or female.
Gender roles: The behaviors, attitudes, and personality traits that are designated as either masculine or feminine in a given culture.
Gender schema theory: This theory of how children form their own gender roles argues that children actively organize others’ behavior, activities, and attributes into gender categories or schemas.
Gender stereotypes: The beliefs and expectations people hold about the typical characteristics, preferences, and behaviors of men and women.
Genderfluid: An individual who may identify as male, female, both, or neither at different times and in different circumstances.
Genderqueer or gender nonbinary: An umbrella term used to describe a wide range of individuals who do not identify with and/or conform to the gender binary.
Gene Selection Theory: The modern theory of evolution by selection by which differential gene replication is the defining process of evolutionary change.
Generalizability: Related to whether the results from the sample can be generalized to a larger population.
Generalize: Generalizing, in science, refers to the ability to arrive at broad conclusions based on a smaller sample of observations. For these conclusions to be true the sample should accurately represent the larger population from which it is drawn.
Gestalt psychology: An attempt to study the unity of experience.
Global subjective well-being: Individuals’ perceptions of and satisfaction with their lives as a whole.
Globus pallidus: A nucleus of the basal ganglia.
Glutamate: An excitatory amino acid neurotransmitter that is widely used by vestibular receptors, afferents, and many neurons in the brain.
Goal: The cognitive representation of a desired state (outcome).
Good genes hypothesis: Proposes that certain physical qualities, like averageness, are attractive because they advertise mate quality—either greater fertility or better genetic traits that lead to better offspring and hence greater reproductive success.
Gray matter: Composes the bark or the cortex of the cerebrum and consists of the cell bodies of the neurons (see also white matter).
Gray matter: The outer grayish regions of the brain comprised of the neurons’ cell bodies.
Gyri: (plural) Folds between sulci in the cortex.
Gyrus: A fold between sulci in the cortex.
Gyrus: (plural form, gyri) A bulge that is raised between or among fissures of the convoluted brain.
Habituation: Occurs when the response to a stimulus decreases with exposure.
Hair cells: The receptor cells of the vestibular system. They are termed hair cells due to the many hairlike cilia that extend from the apical surface of the cell into the gelatin membrane. Mechanical gated ion channels in the tips of the cilia open and close as the cilia bend to cause membrane voltage changes in the hair cell that are proportional to the intensity and direction of motion.
Hallucinations: Perceptual experiences that occur even when there is no stimulus in the outside world generating the experiences. They can be auditory, visual, olfactory (smell), gustatory (taste), or somatic (touch).
Happiness: The popular word for subjective well-being. Scientists sometimes avoid using this term because it can refer to different things, such as feeling good, being satisfied, or even the causes of high subjective well-being.
Hawthorne Effect: An effect in which individuals change or improve some facet of their behavior as a result of their awareness of being observed.
Hawthorne Studies: A series of well-known studies conducted under the leadership of Harvard University researchers, which changed the perspective of scholars and practitioners about the role of human psychology in relation to work behavior.
Hedonic well-being: Component of well-being that refers to emotional experiences, often including measures of positive (e.g., happiness, contentment) and negative affect (e.g., stress, sadness).
Hemoglobin: The oxygen-carrying portion of a red blood cell.
Heritability coefficient: An easily misinterpreted statistical construct that purports to measure the role of genetics in the explanation of differences among individuals.
Heterogeneity: Inter-individual and subgroup differences in level and rate of change over time.
Heuristics: A mental shortcut or rule of thumb that reduces complex mental problems to more simple rule-based decisions.
Heuristics: cognitive (or thinking) strategies that simplify decision making by using mental short-cuts
Highlighting a goal: Prioritizing a focal goal over other goals or temptations by putting more effort into the focal goal.
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.
Homeostasis: The tendency of an organism to maintain a stable state across all the different physiological systems in the body.
Homeostatic set point: An ideal level that the system being regulated must be monitored and compared to.
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.
Homophily: Adolescents tend to associate with peers who are similar to themselves.
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.
Horizontal plane: A slice that runs horizontally through a standing person (i.e., parallel to the floor); slices of brain in this plane divide the top and bottom parts of the brain; this plane is similar to slicing a hamburger bun.
Hormones: Chemicals released by cells in the brain or body that affect cells in other parts of the brain or body.
Hostile attribution bias: The tendency to perceive ambiguous actions by others as aggressive.
Hostile expectation bias: The tendency to assume that people will react to potential conflicts with aggression.
Hostile perception bias: The tendency to perceive social interactions in general as being aggressive.
Hostile sexism: The negative element of ambivalent sexism, which includes the attitudes that women are inferior and incompetent relative to men.
Hot cognition: The mental processes that are influenced by desires and feelings.
Humorism (or humoralism): A belief held by ancient Greek and Roman physicians (and until the 19th century) that an excess or deficiency in any of the four bodily fluids, or humors—blood, black bile, yellow bile, and phlegm—directly affected their health and temperament.
Hyperpolarization: A change in a cell’s membrane potential, making the inside of the cell more negative and decreasing the chance of an action potential.
Hyperpolarizes: When receptor hair cells have mechanically gated channels close, the cell decreases its membrane voltage, which produces less release of neurotransmitters to inhibit the innervating nerve fiber.
Hypothalamic-pituitary-adrenal (HPA) axis: A system that involves the hypothalamus (within the brain), the pituitary gland (within the brain), and the adrenal glands (at the top of the kidneys). This system helps maintain homeostasis (keeping the body’s systems within normal ranges) by regulating digestion, immune function, mood, temperature, and energy use. Through this, the HPA regulates the body’s response to stress and injury.
Hypothalamus: A brain structure located below the thalamus and above the brain stem.
Hypothalamus: A portion of the brain involved in a variety of functions, including the secretion of various hormones and the regulation of hunger and sexual arousal.
Hypothalamus: Part of the diencephalon. Regulates biological drives with pituitary gland.
Hysteria: Term used by the ancient Greeks and Egyptians to describe a disorder believed to be caused by a woman’s uterus wandering throughout the body and interfering with other organs (today referred to as conversion disorder, in which psychological problems are expressed in physical form).
Identity achievement: Individuals have explored different options and then made commitments.
Identity diffusion: Adolescents neither explore nor commit to any roles or ideologies.
Immunocytochemistry: A method of staining tissue including the brain, using antibodies.
Impact bias: A bias in affective forecasting in which one overestimates the strength or intensity of emotion one will experience after some event.
Implemental phase: The second of the two basic stages of self-regulation in which individuals plan specific actions related to their selected goal.
Implicit Association Test: An implicit attitude task that assesses a person’s automatic associations between concepts by measuring the response times in pairing the concepts.
Implicit attitude: An attitude that a person cannot verbally or overtly state.
Implicit learning: Occurs when we acquire information without intent that we cannot easily express.
Implicit measures of attitudes: Measures of attitudes in which researchers infer the participant’s attitude rather than having the participant explicitly report it.
Implicit memory: A type of long-term memory that does not require conscious thought to encode. It's the type of memory one makes without intent.
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).
Inattentional blindness: The failure to notice a fully visible object when attention is devoted to something else.
Inattentional blindness: The failure to notice a fully visible, but unexpected, object or event when attention is devoted to something else.
Inattentional deafness: The auditory analog of inattentional blindness. People fail to notice an unexpected sound or voice when attention is devoted to other aspects of a scene.
Incidental learning: Any type of learning that happens without the intention to learn.
Independent variable: The variable the researcher manipulates and controls in an experiment.
Individual differences: Ways in which people differ in terms of their behavior, emotion, cognition, and development.
Industrial/Organizational psychology: Scientific study of behavior in organizational settings and the application of psychology to understand work behavior.
Information processing theories: Theories that focus on describing the cognitive processes that underlie thinking at any one age and cognitive growth over time.
Informational influence: Conformity that results from a concern to act in a socially approved manner as determined by how others act.
Ingroup: A social group to which an individual identifies or belongs.
Ingroup: Group to which a person belongs.
Inhibitory functioning: Ability to focus on a subset of information while suppressing attention to less relevant information.
Inhibitory postsynaptic potentials: A hyperpolarizing postsynaptic current that causes the membrane potential to become more negative and move away from the threshold of excitation.
Integrated: The process by which the perceptual system combines information arising from more than one modality.
Intention: An agent’s mental state of committing to perform an action that the agent believes will bring about a desired outcome.
Intentional learning: Any type of learning that happens when motivated by intention.
Intentionality: The quality of an agent’s performing a behavior intentionally—that is, with skill and awareness and executing an intention (which is in turn based on a desire and relevant beliefs).
Interaural differences: Differences (usually in time or intensity) between the two ears.
Interference: Other memories get in the way of retrieving a desired memory
Internal validity: The degree to which a cause-effect relationship between two variables has been unambiguously established.
Interoception: The sense of the physiological state of the body. Hunger, thirst, temperature, pain, and other sensations relevant to homeostasis. Visceral input such as heart rate, blood pressure, and digestive activity give rise to an experience of the body’s internal states and physiological reactions to external stimulation. This experience has been described as a representation of “the material me,” and it is hypothesized to be the foundation of subjective feelings, emotion, and self-awareness.
Intersexual selection: A process of sexual selection by which evolution (change) occurs as a consequences of the mate preferences of one sex exerting selection pressure on members of the opposite sex.
Intra- and inter-individual differences: Different patterns of development observed within an individual (intra-) or between individuals (inter-).
Intrasexual competition: A process of sexual selection by which members of one sex compete with each other, and the victors gain preferential mating access to members of the opposite sex.
Intrinsic motivation: Motivation stemming from the benefits associated with the process of pursuing a goal such as having a fulfilling experience.
Introspection: A method of focusing on internal processes.
Invasive Procedure: A procedure that involves the skin being broken or an instrument or chemical being introduced into a body cavity.
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.
Joint attention: Two people attending to the same object and being aware that they both are attending to it.
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 inhibition: A signal produced by a neuron aimed at suppressing the response of nearby neurons.
Lateral rectus muscle: An eye muscle that turns outward in the horizontal plane.
Lateral sulcus: The major fissure that delineates the temporal lobe below the frontal and the parietal lobes.
Lateral vestibulo-spinal tract: Vestibular neurons that project to all levels of the spinal cord on the ipsilateral side to control posture and balance movements.
Lateralized: To the side; used to refer to the fact that specific functions may reside primarily in one hemisphere or the other (e.g., for the majority individuals, the left hemisphere is most responsible for language).
Lesion: A region in the brain that suffered damage through injury, disease, or medical intervention.
Lesion studies: A surgical method in which a part of the animal brain is removed to study its effects on behavior or function.
Lesions: Damage or tissue abnormality due, for example, to an injury, surgery, or a vascular problem.
Lesions: Abnormalities in the tissue of an organism usually caused by disease or trauma.
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.
Lexicon: Words and expressions.
Life course theories: Theory of development that highlights the effects of social expectations of age-related life events and social roles; additionally considers the lifelong cumulative effects of membership in specific cohorts and sociocultural subgroups and exposure to historical events.
Life satisfaction: A person reflects on their life and judges to what degree it is going well, by whatever standards that person thinks are most important for a good life.
Life span theories: Theory of development that emphasizes the patterning of lifelong within- and between-person differences in the shape, level, and rate of change trajectories.
Limbic system: A loosely defined network of nuclei in the brain involved with learning and emotion.
Limbic system: Includes the subcortical structures of the amygdala and hippocampal formation as well as some cortical structures; responsible for aversion and gratification.
Limited capacity: The notion that humans have limited mental resources that can be used at a given time.
Linguistic inquiry and word count: A quantitative text analysis methodology that automatically extracts grammatical and psychological information from a text by counting word frequencies.
Linguistic intergroup bias: A tendency for people to characterize positive things about their ingroup using more abstract expressions, but negative things about their outgroups using more abstract expressions.
Lived day analysis: A methodology where a research team follows an individual around with a video camera to objectively document a person’s daily life as it is lived.
Longitudinal studies: Research method that collects information from individuals at multiple time points over time, allowing researchers to track cohort differences in age-related change to determine cumulative effects of different life experiences.
Longitudinal study: A study that follows the same group of individuals over time.
Lordosis: A physical sexual posture in females that serves as an invitation to mate.
Magnetic resonance imaging: Or MRI is a brain imaging noninvasive technique that uses magnetic energy to generate brain images (also see fMRI).
Magnetic resonance imaging: A set of techniques that uses strong magnets to measure either the structure of the brain (e.g., gray matter and white matter) or how the brain functions when a person performs cognitive tasks (e.g., working memory or episodic memory) or other types of tasks.
Magnification factor: Cortical space projected by an area of sensory input (e.g., mm of cortex per degree of visual field).
Maladaptive: Term referring to behaviors that cause people who have them physical or emotional harm, prevent them from functioning in daily life, and/or indicate that they have lost touch with reality and/or cannot control their thoughts and behavior (also called dysfunctional).
Margin of error: The expected amount of random variation in a statistic; often defined for 95% confidence level.
McGurk effect: An effect in which conflicting visual and auditory components of a speech stimulus result in an illusory percept.
Mechanically gated ion channels: Ion channels located in the tips of the stereocilia on the receptor cells that open/close as the cilia bend toward the tallest/smallest cilia, respectively. These channels are permeable to potassium ions, which are abundant in the fluid bathing the top of the hair cells.
Medial prefrontal cortex: An area of the brain located in the middle of the frontal lobes (at the front of the head), active when people mentalize about the self and others.
Medial temporal lobes: Inner region of the temporal lobes that includes the hippocampus.
Medial vestibulo-spinal tract: Vestibular nucleus neurons project bilaterally to cervical spinal motor neurons for head and neck movement control. The tract principally functions in gaze direction and stability during motion.
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.
Mentalizing: The act of representing the mental states of oneself and others. Mentalizing allows humans to interpret the intentions, beliefs, and emotional states of others.
Mere-exposure effect: The tendency to prefer stimuli that have been seen before over novel ones. There also is a generalized mere-exposure effect shown in a preference for stimuli that are similar to those that have been seen before.
Mesmerism: Derived from Franz Anton Mesmer in the late 18th century, an early version of hypnotism in which Mesmer claimed that hysterical symptoms could be treated through animal magnetism emanating from Mesmer’s body and permeating the universe (and later through magnets); later explained in terms of high suggestibility in individuals.
Metabolism: Breakdown of substances.
Metabolite: A substance necessary for a living organism to maintain life.
Metacognition: Describes the knowledge and skills people have in monitoring and controlling their own learning and memory.
Mimicry: Copying others’ behavior, usually without awareness.
Mirror neurons: Neurons identified in monkey brains that fire both when the monkey performs a certain action and when it perceives another agent performing that action.
Misinformation effect: A memory error caused by exposure to incorrect information between the original event (e.g., a crime) and later memory test (e.g., an interview, lineup, or day in court).
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.
Mock witnesses: A research subject who plays the part of a witness in a study.
Mood-congruent memory: The tendency to be better able to recall memories that have a mood similar to our current mood.
Moratorium: State in which adolescents are actively exploring options but have not yet made identity commitments.
Morph: A face or other image that has been transformed by a computer program so that it is a mixture of multiple images.
Motivated skepticism: A form of bias that can result from having a directional goal in which one is skeptical of evidence despite its strength because it goes against what one wants to believe.
Motivation: The psychological driving force that enables action in the course of goal pursuit.
Motor cortex: Region of the frontal lobe responsible for voluntary movement; the motor cortex has a contralateral representation of the human body.
Multimodal: Of or pertaining to multiple sensory modalities.
Multimodal perception: The effects that concurrent stimulation in more than one sensory modality has on the perception of events and objects in the world.
Multimodal phenomena: Effects that concern the binding of inputs from multiple sensory modalities.
Multisensory convergence zones: Regions in the brain that receive input from multiple unimodal areas processing different sensory modalities.
Multisensory enhancement: See “superadditive effect of multisensory integration.”
Myelin: Fatty tissue, produced by glial cells (see module, “Neurons”) that insulates the axons of the neurons; myelin is necessary for normal conduction of electrical impulses among neurons.
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.
Natural selection: Differential reproductive success as a consequence of differences in heritable attributes.
Nature: The genes that children bring with them to life and that influence all aspects of their development.
Need for closure: The desire to come to a decision that will resolve ambiguity and conclude an issue.
Negative feelings: Undesirable and unpleasant feelings that people tend to avoid if they can. Moods and emotions such as depression, anger, and worry are examples.
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 impulse: An electro-chemical signal that enables neurons to communicate.
Neural induction: A process that causes the formation of the neural tube.
Neural plasticity: The ability of synapses and neural pathways to change over time and adapt to changes in neural process, behavior, or environment.
Neuroblasts: Brain progenitor cells that asymmetrically divide into other neuroblasts or nerve cells.
Neurodevelopmental: Processes that influence how the brain develops either in utero or as the child is growing up.
Neuroendocrinology: The study of how the brain and hormones act in concert to coordinate the physiology of the body.
Neuroepithelium: The lining of the neural tube.
Neuroscience: The study of the nervous system.
Neuroscience methods: A research method that deals with the structure or function of the nervous system and brain.
Neurotransmitter: A chemical substance produced by a neuron that is used for communication between neurons.
Neurotransmitters: A chemical compound used to send signals from a receptor cell to a neuron, or from one neuron to another. Neurotransmitters can be excitatory, inhibitory, or modulatory and are packaged in small vesicles that are released from the end terminals of cells.
Neurotransmitters: Chemical substance released by the presynaptic terminal button that acts on the postsynaptic cell.
Nociception: The neural process of encoding noxious stimuli, the sensory input from nociceptors. Not necessarily painful, and crucially not necessary for the experience of pain.
Nociceptors: High-threshold sensory receptors of the peripheral somatosensory nervous system that are capable of transducing and encoding noxious stimuli. Nociceptors send information about actual or impending tissue damage to the brain. These signals can often lead to pain, but nociception and pain are not the same.
Nomenclature: Naming conventions.
Nonassociative learning: Occurs when a single repeated exposure leads to a change in behavior.
Nonconscious goal activation: When activation occurs outside a person’s awareness, such that the person is unaware of the reasons behind her goal-directed thoughts and behaviors.
Noninvasive procedure: A procedure that does not require the insertion of an instrument or chemical through the skin or into a body cavity.
Normative influence: Conformity that results from a concern for what other people think of us.
Noxious stimulus: A stimulus that is damaging or threatens damage to normal tissues.
Nucleus: Collection of nerve cells found in the brain which typically serve a specific function.
Nucleus accumbens: A region of the basal forebrain located in front of the preoptic region.
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.
Occipital lobe: The back most (posterior) part of the cerebrum; involved in vision.
Occipital lobe: The back part of the cerebrum, which houses the visual areas.
Ocial touch hypothesis: Proposes that social touch is a distinct domain of touch. C-tactile afferents form a special pathway that distinguishes social touch from other types of touch by selectively firing in response to touch of social-affective relevance; thus sending affective information parallel to the discriminatory information from the Aβ-fibers. In this way, the socially relevant touch stands out from the rest as having special positive emotional value and is processed further in affect-related brain areas such as the insula.
Oculomotor nuclei: Includes three neuronal groups in the brainstem, the abducens nucleus, the oculomotor nucleus, and the trochlear nucleus, whose cells send motor commands to the six pairs of eye muscles.
Oculomotor nucleus: A group of cells in the middle brainstem that contain subgroups of neurons that project to the medial rectus, inferior oblique, inferior rectus, and superior rectus muscles of the eyes through the 3rd cranial nerve.
O*Net: A vast database of occupational information containing data on hundreds of jobs.
Operant conditioning: Describes stimulus-response associative learning.
Operational definitions: How researchers specifically measure a concept.
Opponent Process Theory: Theory of color vision that assumes there are four different basic colors, organized into two pairs (red/green and blue/yellow) and proposes that colors in the world are encoded in terms of the opponency (or difference) between the colors in each pair. There is an additional black/white pair responsible for coding light contrast.
Orbital frontal cortex: A region of the frontal lobes of the brain above the eye sockets.
Otoconia: Small calcium carbonate particles that are packed in a layer on top of the gelatin membrane that covers the otolith receptor hair cell stereocilia.
Otolith receptors: Two inner ear vestibular receptors (utricle and saccule) that transduce linear accelerations and head tilt relative to gravity into neural signals that are then transferred to the brain.
Outgroup: A social group to which an individual does not identify or belong.
Outgroup: Group to which a person does not belong.
Overconfident: The bias to have greater confidence in your judgment than is warranted based on a rational assessment.
Oxygenated hemoglobin: Hemoglobin carrying oxygen.
Pain: Defined as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage,” according to the International Association for the Study of Pain.
Parameter: A numerical result summarizing a population (e.g., mean, proportion).
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.
Parasympathetic nervous system (PNS): One of the two major divisions of the autonomic nervous system, responsible for stimulation of “rest and digest” activities.
Parietal lobe: An area of the cerebrum just behind the central sulcus that is engaged with somatosensory and gustatory sensation.
Parietal lobe: The part of the cerebrum between the frontal and occipital lobes; involved in bodily sensations, visual attention, and integrating the senses.
Participant demand: When participants behave in a way that they think the experimenter wants them to behave.
Perceptual learning: Occurs when aspects of our perception changes as a function of experience.
Periaqueductal gray: The gray matter in the midbrain near the cerebral aqueduct.
Peripheral nervous system: The part of the nervous system that is outside the brain and spinal cord.
Phantom pain: Pain that appears to originate in an amputated limb.
Pharmacokinetics: The action of a drug through the body, including absorption, distribution, metabolism, and excretion.
Phonemic awareness: Awareness of the component sounds within words.
Photo spreads: A selection of normally small photographs of faces given to a witness for the purpose of identifying a perpetrator.
Photoactivation: A photochemical reaction that occurs when light hits photoreceptors, producing a neural signal.
Phrenology: A now-discredited field of brain study, popular in the first half of the 19th century that correlated bumps and indentations of the skull with specific functions of the brain.
Piaget’s theory: Theory that development occurs through a sequence of discontinuous stages: the sensorimotor, preoperational, concrete operational, and formal operational stages.
Pinna: Visible part of the outer ear.
Placebo effect: Effects from a treatment that are not caused by the physical properties of a treatment but by the meaning ascribed to it. These effects reflect the brain’s own activation of modulatory systems, which is triggered by positive expectation or desire for a successful treatment. Placebo analgesia is the most well-studied placebo effect and has been shown to depend, to a large degree, on opioid mechanisms. Placebo analgesia can be reversed by the pharmacological blocking of  opioid receptors. The word “placebo” is probably derived from the Latin word “placebit” (“it will please”).
Placebo effect: When receiving special treatment or something new affects human behavior.
Planning fallacy: A cognitive bias in which one underestimates how long it will take to complete a task.
Polypharmacy: The use of many medications.
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.
Population: A larger collection of individuals that we would like to generalize our results to.
Positive feelings: Desirable and pleasant feelings. Moods and emotions such as enjoyment and love are examples.
Positron: A particle having the same mass and numerically equal but positive charge as an electron.
Positron emission tomography: A technique that uses radio-labelled ligands to measure the distribution of different neurotransmitter receptors in the brain or to measure how much of a certain type of neurotransmitter is released when a person is given a specific type of drug or does a particularly cognitive task.
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.
Positron emission tomography (PET): A neuroimaging technique that measures brain activity by detecting the presence of a radioactive substance in the brain that is initially injected into the bloodstream and then pulled in by active brain tissue.
Practitioner-Scholar Model: A model of training of professional psychologists that emphasizes clinical practice.
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.
Preoptic area: A region in the anterior hypothalamus involved in generating and regulating male sexual behavior.
Preoptic region: A part of the anterior hypothalamus.
Prevention focus: One of two self-regulatory orientations emphasizing safety, responsibility, and security needs, and viewing goals as “oughts.” This self-regulatory focus seeks to avoid losses (the presence of negatives) and approach non-losses (the absence of negatives).
Primary auditory cortex: A region of the cortex devoted to the processing of simple auditory information.
Primary Motor Cortex: A strip of cortex just in front of the central sulcus that is involved with motor control.
Primary Somatosensory Cortex: A strip of cerebral tissue just behind the central sulcus engaged in sensory reception of bodily sensations.
Primary visual cortex: A region of the cortex devoted to the processing of simple visual information.
Primary visual cortex (V1): Brain region located in the occipital cortex (toward the back of the head) responsible for processing basic visual information like the detection, thickness, and orientation of simple lines, color, and small-scale motion.
Primed: A process by which a concept or behavior is made more cognitively accessible or likely to occur through the presentation of an associated concept.
Priming: A stimulus presented to a person reminds him or her about other ideas associated with the stimulus.
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.
Processing speed: The time it takes individuals to perform cognitive operations (e.g., process information, react to a signal, switch attention from one task to another, find a specific target object in a complex picture).
Processing speed: The speed with which an individual can perceive auditory or visual information and respond to it.
Progress: The perception of reducing the discrepancy between one’s current state and one’s desired state in goal pursuit.
Projection: A social perceiver’s assumption that the other person wants, knows, or feels the same as the perceiver wants, know, or feels.
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.
Promotion focus: One of two self-regulatory orientations emphasizing hopes, accomplishments, and advancement needs, and viewing goals as “ideals.” This self-regulatory focus seeks to approach gains (the presence of positives) and avoid non-gains (the absence of positives).
Proprioceptive: Sensory information regarding muscle position and movement arising from receptors in the muscles, tendons, and joints.
Prototype: A typical, or average, member of a category. Averageness increases attractiveness.
Psychoactive drugs: A drug that changes mood or the way someone feels.
Psychogenesis: Developing from psychological origins.
Psychological adaptations: Mechanisms of the mind that evolved to solve specific problems of survival or reproduction; conceptualized as information processing devices.
Psychological control: Parents’ manipulation of and intrusion into adolescents’ emotional and cognitive world through invalidating adolescents’ feelings and pressuring them to think in particular ways.
Psychological essentialism: The belief that members of a category have an unseen property that causes them to be in the category and to have the properties associated with it.
Psychometric approach: Approach to studying intelligence that examines performance on tests of intellectual functioning.
Psychopathology: Illnesses or disorders that involve psychological or psychiatric symptoms.
Psychophysics: Study of the relationships between physical stimuli and the perception of those stimuli.
Psychophysiological methods: Any research method in which the dependent variable is a physiological measure and the independent variable is behavioral or mental (such as memory).
Psychotropic drug: A drug that changes mood or emotion, usually used when talking about drugs prescribed for various mental conditions (depression, anxiety, schizophrenia, etc.).
Punishment: Inflicting pain or removing pleasure for a misdeed. Punishment decreases the likelihood that a behavior will be repeated.
P-value: The probability of observing a particular outcome in a sample, or more extreme, under a conjecture about the larger population or process.
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 genetics: Scientific and mathematical methods for inferring genetic and environmental processes based on the degree of genetic and environmental similarity among organisms.
Quasi-experimental design: An experiment that does not require random assignment to conditions.
Random assignment: Using a probability-based method to divide a sample into treatment groups.
Random assignment: Assigning participants to receive different conditions of an experiment by chance.
Random sampling: Using a probability-based method to select a subset of individuals for the sample from the population.
Realism: A point of view that emphasizes the importance of the senses in providing knowledge of the external world.
Recall: Type of memory task where individuals are asked to remember previously learned information without the help of external cues.
Receptive field: The portion of the world to which a neuron will respond if an appropriate stimulus is present there.
Recoding: The ubiquitous process during learning of taking information in one form and converting it to another form, usually one more easily remembered.
Recognition: Type of memory task where individuals are asked to remember previously learned information with the assistance of cues.
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.
Relational aggression: Intentionally harming another person’s social relationships, feelings of acceptance, or inclusion within a group.
Reliablility: The consistency of test scores across repeated assessments. For example, test-retest reliability examines the extent to which scores change over time.
Representativeness heuristic: A heuristic in which the likelihood of an object belonging to a category is evaluated based on the extent to which the object appears similar to one’s mental representation of the category.
Resting membrane potential: The voltage inside the cell relative to the voltage outside the cell while the cell is a rest (approximately -70 mV).
Retrieval: Process by which information is accessed from memory and utilized.
Retrieval: The process of accessing stored information.
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.
Reward value: A neuropsychological measure of an outcome’s affective importance to an organism.
Rods: Photoreceptors that are very sensitive to light and are mostly responsible for night vision.
Rostrocaudal: A front-back plane used to identify anatomical structures in the body and the brain.
Rubber hand illusion: The false perception of a fake hand as belonging to a perceiver, due to multimodal sensory information.
Sagittal plane: A slice that runs vertically from front to back; slices of brain in this plane divide the left and right side of the brain; this plane is similar to slicing a baked potato lengthwise.
Sample: The collection of individuals on which we collect data.
Sapir-Whorf hypothesis: The hypothesis that the language that people use determines their thoughts.
Satiation: The state of being full to satisfaction and no longer desiring to take on more.
Satisfaction: Correspondence between an individual’s needs or preferences and the rewards offered by the environment.
Satisfactoriness: Correspondence between an individual’s abilities and the ability requirements of the environment.
Schema: A mental model or representation that organizes the important information about a thing, person, or event (also known as a script).
Schema (plural: schemata): A memory template, created through repeated exposure to a particular class of objects or events.
Schemas: The gender categories into which, according to gender schema theory, children actively organize others’ behavior, activities, and attributes.
Scientist-practitioner model: A model of training of professional psychologists that emphasizes the development of both research and clinical skills.
Scientist-practitioner model: The dual focus of I/O psychology, which entails practical questions motivating scientific inquiry to generate knowledge about the work-person interface and the practitioner side applying this scientific knowledge to organizational problems.
Selective attention: The ability to select certain stimuli in the environment to process, while ignoring distracting information.
Selective listening: A method for studying selective attention in which people focus attention on one auditory stream of information while deliberately ignoring other auditory information.
Self-control: The capacity to control impulses, emotions, desires, and actions in order to resist a temptation and adhere to a valued goal.
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.
Self-perceptions of aging: An individual’s perceptions of their own aging process; positive perceptions of aging have been shown to be associated with greater longevity and health.
Self-regulation: The processes through which individuals alter their emotions, desires, and actions in the course of pursuing a goal.
Semantic memory: The more or less permanent store of knowledge that people have.
Semicircular canals: A set of three inner ear vestibular receptors (horizontal, anterior, posterior) that transduce head rotational accelerations into head rotational velocity signals that are then transferred to the brain. There are three semicircular canals in each ear, with the major planes of each canal being orthogonal to each other.
Sensitization: Increased responsiveness of nociceptive neurons to their normal input and/or recruitment of a response to normally subthreshold inputs. Clinically, sensitization may only be inferred indirectly from phenomena such as hyperalgesia or allodynia. Sensitization can occur in the central nervous system (central sensitization) or in the periphery (peripheral sensitization).
Sensitization: Occurs when the response to a stimulus increases with exposure
Sensorimotor stage: Period within Piagetian theory from birth to age 2 years, during which children come to represent the enduring reality of objects.
Sensory modalities: A type of sense; for example, vision or audition.
Sex: Biological category of male or female as defined by physical differences in genetic composition and in reproductive anatomy and function.
Sexual harassment: A form of gender discrimination based on unwanted treatment related to sexual behaviors or appearance.
Sexual orientation: Refers to the direction of emotional and erotic attraction toward members of the opposite sex, the same sex, or both sexes.
Sexual selection: The evolution of characteristics because of the mating advantage they give organisms.
Sexual strategies theory: A comprehensive evolutionary theory of human mating that defines the menu of mating strategies humans pursue (e.g., short-term casual sex, long-term committed mating), the adaptive problems women and men face when pursuing these strategies, and the evolved solutions to these mating problems.
Shadowing: A task in which the individual is asked to repeat an auditory message as it is presented.
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.
Simulation: Imaginary or real imitation of other people’s behavior or feelings.
Simulation: The process of representing the other person’s mental state.
Situation model: A mental representation of an event, object, or situation constructed at the time of comprehending a linguistic description.
Social brain: The set of neuroanatomical structures that allows us to understand the actions and intentions of other people.
Social brain hypothesis: The hypothesis that the human brain has evolved, so that humans can maintain larger ingroups.
Social categorization: The act of mentally classifying someone into a social group (e.g., as female, elderly, a librarian).
Social cognition: The study of how people think about the social world.
Social learning theory: This theory of how children form their own gender roles argues that gender roles are learned through reinforcement, punishment, and modeling.
Social network: Network of people with whom an individual is closely connected; social networks provide emotional, informational, and material support and offer opportunities for social engagement.
Social networks: Networks of social relationships among individuals through which information can travel.
Social support: A subjective feeling of psychological or physical comfort provided by family, friends, and others.
Social touch hypothesis: Proposes that social touch is a distinct domain of touch. C-tactile afferents form a special pathway that distinguishes social touch from other types of touch by selectively firing in response to touch of social-affective relevance; thus sending affective information parallel to the discriminatory information from the Aβ-fibers. In this way, the socially relevant touch stands out from the rest as having special positive emotional value and is processed further in affect-related brain areas such as the insula.
Society for Industrial and Organizational Psychology (SIOP): A professional organization bringing together academics and practitioners who work in I/O psychology and related areas. It is Division 14 of the American Psychological Association (APA).
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.
Socioemotional Selectivity Theory: Theory proposed to explain the reduction of social partners in older adulthood; posits that older adults focus on meeting emotional over information-gathering goals, and adaptively select social partners who meet this need.
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.
Somatogenesis: Developing from physical/bodily origins.
Somatosensory (body sensations) cortex: The region of the parietal lobe responsible for bodily sensations; the somatosensory cortex has a contralateral representation of the human body.
Somatosensory cortex: Consists of primary sensory cortex (S1) in the postcentral gyrus in the parietal lobes and secondary somatosensory cortex (S2), which is defined functionally and found in the upper bank of the lateral sulcus, called the parietal operculum. Somatosensory cortex also includes parts of the insular cortex.
Somatotopically organized: When the parts of the body that are represented in a particular brain region are organized topographically according to their physical location in the body (see Figure 2 illustration).
Spatial principle of multisensory integration: The finding that the superadditive effects of multisensory integration are observed when the sources of stimulation are spatially related to one another.
Spatial resolution: The degree to which one can separate a single object in space from another.
Spatial resolution: A term that refers to how small the elements of an image are; high spatial resolution means the device or technique can resolve very small elements; in neuroscience it describes how small of a structure in the brain can be imaged.
Specific abilities: Cognitive abilities that contain an appreciable component of g or general ability, but also contain a large component of a more content-focused talent such as mathematical, spatial, or verbal ability; patterns of specific abilities channel development down different paths as a function of an individual’s relative strengths and weaknesses.
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.
Spinothalamic tract: Runs through the spinal cord’s lateral column up to the thalamus. C-fibers enter the dorsal horn of the spinal cord and form a synapse with a neuron that then crosses over to the lateral column and becomes part of the spinothalamic tract.
Split-brain patient: A patient who has had most or all of his or her corpus callosum severed.
Statistic: A numerical result computed from a sample (e.g., mean, proportion).
Statistical significance: A result is statistically significant if it is unlikely to arise by chance alone.
Stereocilia: Hairlike projections from the top of the receptor hair cells. The stereocilia are arranged in ascending height and when displaced toward the tallest cilia, the mechanical gated channels open and the cell is excited (depolarized). When the stereocilia are displaced toward the smallest cilia, the channels close and the cell is inhibited (hyperpolarized).
Stereotypes: Our general beliefs about the traits or behaviors shared by group of people.
Stereotypes: The beliefs or attributes we associate with a specific social group. Stereotyping refers to the act of assuming that because someone is a member of a particular group, he or she possesses the group’s attributes. For example, stereotyping occurs when we assume someone is unemotional just because he is man, or particularly athletic just because she is African American.
Storage: The stage in the learning/memory process that bridges encoding and retrieval; the persistence of memory over time.
Stress: A threat or challenge to our well-being. Stress can have both a psychological component, which consists of our subjective thoughts and feelings about being threatened or challenged, as well as a physiological component, which consists of our body’s response to the threat or challenge (see “fight or flight response”).
Stria terminalis: A band of fibers that runs along the top surface of the thalamus.
Structuralism: A school of American psychology that sought to describe the elements of conscious experience.
Subcortical: Structures that lie beneath the cerebral cortex, but above the brain stem.
Subjective age: A multidimensional construct that indicates how old (or young) a person feels and into which age group a person categorizes him- or herself
Subjective well-being: The name that scientists give to happiness—thinking and feeling that our lives are going very well.
Subjective well-being scales: Self-report surveys or questionnaires in which participants indicate their levels of subjective well-being, by responding to items with a number that indicates how well off they feel.
Subliminal perception: The ability to process information for meaning when the individual is not consciously aware of that information.
Successful aging: Includes three components: avoiding disease, maintaining high levels of cognitive and physical functioning, and having an actively engaged lifestyle.
Sulci: (plural) Grooves separating folds of the cortex.
Sulcus: A groove separating folds of the cortex.
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.
Superior temporal sulcus: The sulcus (a fissure in the surface of the brain) that separates the superior temporal gyrus from the middle temporal gyrus. Located in the temporal lobes (parallel to the ears), it is involved in perception of biological motion or the movement of animate objects.
Supernatural: Developing from origins beyond the visible observable universe.
Sympathetic nervous system: A branch of the autonomic nervous system that controls many of the body’s internal organs. Activity of the SNS generally mobilizes the body’s fight or flight response.
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.
Sympathetic nervous system (SNS): One of the two major divisions of the autonomic nervous system, responsible for stimulation of “fight or flight” activities.
Synapse: Junction between the presynaptic terminal button of one neuron and the dendrite, axon, or soma of another postsynaptic neuron.
Synapse: The tiny space separating neurons.
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.
Synchrony: Two people displaying the same behaviors or having the same internal states (typically because of mutual mimicry).
Syndrome: Involving a particular group of signs and symptoms.
Synesthesia: The blending of two or more sensory experiences, or the automatic activation of a secondary (indirect) sensory experience due to certain aspects of the primary (direct) sensory stimulation.
Syntax: Rules by which words are strung together to form sentences.
System 1: Our intuitive decision-making system, which is typically fast, automatic, effortless, implicit, and emotional.
System 2: Our more deliberative decision-making system, which is slower, conscious, effortful, explicit, and logical.
Temporal lobe: An area of the cerebrum that lies below the lateral sulcus; it contains auditory and olfactory (smell) projection regions.
Temporal lobe: The part of the cerebrum in front of (anterior to) the occipital lobe and below the lateral fissure; involved in vision, auditory processing, memory, and integrating vision and audition.
Temporal parietal junction: The area where the temporal lobes (parallel to the ears) and parieta lobes (at the top of the head toward the back) meet. This area is important in mentalizing and distinguishing between the self and others.
Temporal resolution: A term that refers to how small a unit of time can be measured; high temporal resolution means capable of resolving very small units of time; in neuroscience it describes how precisely in time a process can be measured in the brain.
Temporal resolution: The degree to which one can separate a single point in time from another.
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.
Thalamus: A structure in the midline of the brain located between the midbrain and the cerebral cortex.
Theory of mind: The human capacity to understand minds, a capacity that is made up of a collection of concepts (e.g., agent, intentionality) and processes (e.g., goal detection, imitation, empathy, perspective taking).
Third-person perspective: Observations made by individuals in a way that can be independently confirmed by other individuals so as to lead to general, objective understanding. With respect to consciousness, third-person perspectives make use of behavioral and neural measures related to conscious experiences.
Threshold of excitation: Specific membrane potential that the neuron must reach to initiate an action potential.
Tip-of-the-tongue phenomenon: The inability to pull a word from memory even though there is the sensation that that word is available.
“Top-down” or internal causes of happiness: The person’s outlook and habitual response tendencies that influence their happiness—for example, their temperament or optimistic outlook on life.
Torsion: A rotational eye movement around the line of sight that consists of a clockwise or counterclockwise direction.
“Traitement moral” (moral treatment): A therapeutic regimen of improved nutrition, living conditions, and rewards for productive behavior that has been attributed to Philippe Pinel during the French Revolution, when he released mentally ill patients from their restraints and treated them with compassion and dignity rather than with contempt and denigration.
Transcranial direct current stimulation (tDCS): A neuroscience technique that passes mild electrical current directly through a brain area by placing small electrodes on the skull.
Transcranial magnetic stimulation (TMS): A neuroscience technique whereby a brief magnetic pulse is applied to the head that temporarily induces a weak electrical current that interferes with ongoing activity.
Transduction: The mechanisms that convert stimuli into electrical signals that can be transmitted and processed by the nervous system. Physical or chemical stimulation creates action potentials in a receptor cell in the peripheral nervous system, which is then conducted along the axon to the central nervous system.
Transduction: A process in which physical energy converts into neural energy.
Transfer-appropriate processing: A principle that states that memory performance is superior when a test taps the same cognitive processes as the original encoding activity.
Transgender: A term used to describe individuals whose gender does not match their biological sex.
Transverse plane: See “horizontal plane.”
Trephination: The drilling of a hole in the skull, presumably as a way of treating psychological disorders.
Trichromacy theory: Theory that proposes that all of your color perception is fundamentally based on the combination of three (not two, not four) different color signals.
Twin studies: A behavior genetic research method that involves comparison of the similarity of identical (monozygotic; MZ) and fraternal (dizygotic; DZ) twins.
Tympanic membrane: Ear drum, which separates the outer ear from the middle ear.
Typicality: The difference in “goodness” of category members, ranging from the most typical (the prototype) to borderline members.
Under-determined or misspecified causal models: Psychological frameworks that miss or neglect to include one or more of the critical determinants of the phenomenon under analysis.
Unimodal: Of or pertaining to a single sensory modality.
Unimodal components: The parts of a stimulus relevant to one sensory modality at a time.
Unimodal cortex: A region of the brain devoted to the processing of information from a single sensory modality.
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).
Vergence angle: The angle between the line of sight for the two eyes. Low vergence angles indicate far-viewing objects, whereas large angles indicate viewing of near objects.
Vestibular compensation: Following injury to one side of vestibular receptors or the vestibulocochlear nerve, the central vestibular nuclei neurons gradually recover much of their function through plasticity mechanisms. The recovery is never complete, however, and extreme motion environments can lead to dizziness, nausea, problems with balance, and spatial memory.
Vestibular efferents: Nerve fibers originating from a nucleus in the brainstem that project from the brain to innervate the vestibular receptor hair cells and afferent nerve terminals. Efferents have a modulatory role on their targets, which is not well understood.
Vestibular system: Consists of a set of motion and gravity detection receptors in the inner ear, a set of primary nuclei in the brainstem, and a network of pathways carrying motion and gravity signals to many regions of the brain.
Vestibulocochlear nerve: The VIIIth cranial nerve that carries fibers innervating the vestibular receptors and the cochlea.
Vestibulo-ocular reflex: Coordination of motion information with visual information that allows you to maintain your gaze on an object while you move.
Vestibuloocular reflex: Eye movements produced by the vestibular brainstem that are equal in magnitude and opposite in direction to head motion. The VOR functions to maintain visual stability on a point of interest and is nearly perfect for all natural head movements.
Violence: Aggression intended to cause extreme physical harm, such as injury or death.
Visual cortex: The part of the brain that processes visual information, located in the back of the brain.
Visual hemifield: The half of visual space (what we see) on one side of fixation (where we are looking); the left hemisphere is responsible for the right visual hemifield, and the right hemisphere is responsible for the left visual hemifield.
Visual perspective taking: Can refer to visual perspective taking (perceiving something from another person’s spatial vantage point) or more generally to effortful mental state inference (trying to infer the other person’s thoughts, desires, emotions).
Voltage: The difference in electric charge between two points.
Wernicke’s area: A language area in the temporal lobe where linguistic information is comprehended (Also see Broca’s area).
What pathway: Pathway of neural processing in the brain that is responsible for your ability to recognize what is around you.
Where-and-How pathway: Pathway of neural processing in the brain that is responsible for you knowing where things are in the world and how to interact with them.
White coat hypertension: A phenomenon in which patients exhibit elevated blood pressure in the hospital or doctor’s office but not in their everyday lives.
White matter: The inner whitish regions of the cerebrum comprised of the myelinated axons of neurons in the cerebral cortex.
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.
Work and organizational psychology: Preferred name for I/O psychology in Europe.
Working memory: Short transitory memory processed in the hippocampus.
Working memory: The ability to maintain information over a short period of time, such as 30 seconds or less.
Working memory: The form of memory we use to hold onto information temporarily, usually for the purposes of manipulation.
Working memory: Memory system that allows for information to be simultaneously stored and utilized or manipulated.