Action potential.

Neuronal signaling process during which a neuron’s membrane potential polarizes rapidly along its axon, eventually triggering the release of neurotransmitters into the synaptic cleft.

Action tendency.

As defined by Arnold, a bodily response (e.g., acceleration in heart rate) that results from an emotional appraisal and that prepares the body for action. An action tendency makes appraisal-congruent behaviors more likely than appraisal-incongruent behaviors.

Addiction.

Chronically relapsing condition that is characterized by compulsive reward consumption and a negative affective tone when rewards are unavailable.

Adrenaline.

Bodily chemical that has an arousing or activating effect. It is released by the adrenal gland into the blood stream where it acts as a hormone. Adrenaline is also released in the brain where it acts as a neurotransmitter.

Affect.

Feeling states that are simpler or more basic than emotions. For example, states that can be differentiated based on valence only are typically referred to as affective.

Affect labeling.

Explicit naming of an experienced emotion. It has been shown to reduce affective responses.

Affective priming.

In an affective priming paradigm, participants are exposed to prime-target sequences, and the affective relationship between primes and targets is either congruous or incongruous. Target classifications are facilitated for congruous relative to incongruous cases.

Agonists.

Pharmacological agents that enhance the activity of a particular bodily chemical (e.g., neurotransmitter).

American Psychological Association.

A body that organizes researching and practicing psychologists in North America. Among other things, the APA sets ethical standards for their work.

Amygdala.

Small, roundish nucleus, reminiscent of an almond, that is situated in the medial temporal lobe. It is located anteriorly to the hippocampus.

Antagonists.

Pharmacological agents that inhibit the activity of a particular bodily chemical (e.g., neurotransmitter).

Antecedent-focused emotion regulation.

Emotion regulation strategy that tackles the input to a putative emotion system.

Anterior.

Front of a structure.

Anxiety.

Term that is often used to refer to fearful states. Different researchers use different criteria to define anxiety (e.g., that a threat is prospective rather than imminent). At present it is still unclear whether and how it can be distinguished from fear.

Anxiety disorder.

Condition diagnosed when individuals experience excessive fears that prevent them from leading an ordinary life. There are different types of anxiety disorders; the most common are phobias.

Appraisals.

Cognitive evaluations of an event. Depending on appraisal outcomes, individuals may feel an emotion.

Arginine vasopressin.

[Page 447]Hormone/peptide and neurotransmitter/neuropeptide that is structurally very similar to oxytocin. Whereas oxytocin seems more relevant to female emotions, vasopressin seems more relevant to male emotions. Within the context of attachment formation, these two chemicals have overlapping albeit sex-specific functions.

Attachment styles.

According to Ainsworth and colleagues, these are different forms of social bonds children develop toward their mother or other caretakers. They include secure and insecure attachments.

Autism.

Neurodevelopmental disorder characterized by marked socioemotional deficits.

Automaton.

A machine. Descartes viewed the body as an automaton that only in the case of humans is governed by a soul.

Autonomic nervous system.

Part of the peripheral nervous system. It operates involuntarily and is responsible for monitoring and regulating the function of bodily organs.

Balloon Analogue Risk Task.

Computer-based task that involves participants pumping up virtual balloons and earning money for each pump as long as the balloon remains intact. BART is used as an implicit measure for risk taking.

Basal ganglia.

Collection of nuclei situated in the basal center of the cerebrum. They form important connections with diencephalon and cortex.

Basic emotions.

Relates to Tomkins’s idea of primary affects. Basic emotions are typically identified based on a set of defining criteria (e.g., functionality, associated behaviors).

Behaviorism.

Theoretical approach that became popular in the first half of the 20th century. Its main tenet is that mental processes cannot be observed or measured, and that therefore researchers should focus instead on observing and measuring behavior.

Behavior therapy.

Clinical psychological approach for the treatment of mental disorders. It is based on the principles of classical and operant conditioning.

Benzodiazepines.

Class of drugs that facilitates the activity of GABA in the brain and therefore has a sedative effect. Benzodiazepines are often prescribed to individuals with anxiety disorders.

Beta-endorphins.

Chemical messengers that serve as endogenous opioids or “natural painkillers.”

Bottom-up.

Term that describes mental processes arising from sensory stimuli that stand out from other stimuli (e.g., brighter, louder). These stimuli are said to capture attention via bottom-up processes.

Brainstem.

The most ventral part of the brain that connects with the spinal cord.

CAMP response element binding protein.

Protein that helps transcribe the DNA sequence. It is called a transcription factor.

Catecholamines.

Chemical messengers of the monoamine family that contain the organic compound catechol. Catecholamines include dopamine, norepinephrine, and epinephrine.

Central nervous system.

Part of the nervous system that serves as the main information-processing hub. In vertebrates, it is comprised of the brain and the spinal cord.

Cerebellum.

Brain structure located at the posterior base of the cerebrum. It looks like a small replica of the cerebrum.

Cerebrum.

The brain’s largest and uppermost part. Its three main components are the basal ganglia, the white matter, and the gray matter of the cortex.

Choline.

Essential nutrient of the vitamin B family that is available in most animal products such as eggs and meat.

Chronic pain.

[Page 448]Clinical condition in which individuals suffer from pain for more than 6 months (DSM-5). The condition may be caused by tissue damage and/or psychological stress.

Cingulate gyrus.

Structure that sits medially, forming part of the inner walls of the two hemispheres. It stretches like a belt around the corpus callosum from frontal to parietal lobe.

Circumplex model.

Model of emotions developed by James Russell. It holds that emotions have a circular relationship that can be characterized by two orthogonal dimensions: valence and arousal.

Cognitive arousal theory.

Emotion theory proposed by Schachter and Singer. It holds that emotions depend on the cognitive interpretation of unspecific bodily arousal.

Cognitive restructuring.

Emotion regulation technique whereby individuals obtain new information and change the way they think about and evaluate existing information.

Component process model.

Emotion model proposed by Klaus Scherer. According to the model, emotions arise from a componential appraisal process that operates in a sequential fashion. Its main components include a relevance check, an implications check, an assessment of coping potentials, and an assessment of an event’s normative significance.

COMT gene.

Gene that regulates the production of the catechol-O-methyltransferase (COMT) protein, a protein that inactivates dopamine in the synapse. In humans, part of this gene comes in two variants (Met/Val) that make the resulting protein more or less effective.

Conditioned stimulus.

Stimulus that elicits the same response as an unconditioned stimulus with which it was previously paired. The elicited response is learned rather than innate.

Congenital adrenal hyperplasia.

Genetic disorder that impacts hormonal production in the adrenal gland. Excessive or deficient sex hormones affect the individual’s development of primary and secondary sexual characteristics.

Connectivity.

In neuroscience, this term denotes the structural or functional relation between two or more regions. Structures that are connected via fiber tracts and/or whose activity seems temporally coupled are said to show structural and/or functional connectivity, respectively.

Consolidation.

Mental process during which information previously activated in short-term or working memory becomes durable. Short-term or working memory content is moved into long-term memory.

Constructionist account.

Account of emotions that grew out of the dimensional approach. It holds that emotions are constructed from core affect and other processes including the attribution of core affect to an event, appraisals, and bodily responses.

Convergent evolution.

Describes instances in which two species evolved the same characteristic independently. This characteristic was absent in the common ancestor from which they evolved.

Core affect.

Defined by Russell as a basic affective experience that can be fully described based on valence and arousal.

Cortex.

Latin word for “tree bark.” As a neuroanatomical term, it describes the folding of neuronal layers around the brain’s white matter.

Cranial nerves.

Set of 12 nerves that emerge directly from the brain into the body without running through the spinal cord. Their name derives from the word cranium, which means “skull.”

Cultural anthropology.

[Page 449]Study of humankind as focused on culture and society.

Culture.

Group-specific practice emerging from the interaction between a group and its environment.

Cumulative learning.

Cultural phenomenon whereby individuals acquire a behavior that is then preserved and possibly enhanced within their group across several generations. It is also referred to as cultural transmission.

Cytoarchitecture.

Term with two major components: cyto- and architecture. Cyto-is a prefix specifying something as cellular. It derives from the Greek term kutos, for “hollow.” Together with the term architecture, it refers to the cellular composition of tissue.

Deception techniques.

Psychological techniques that disguise the true purpose of an experiment by giving participants false information. These techniques are ethically sensitive and have to be used with care.

Declarative memory.

The conscious, long-term memory of facts and life events that one can recount verbally.

Default network.

Brain system comprising a set of regions (e.g., medial prefrontal cortex, medial temporal cortex) that are more active during wakeful rest than effortful thought and that are possibly engaged in mind wandering.

Defense cascade.

Term that describes the behavioral responses to threat and outlines two phases. In an initial inhibitory phase, individuals orient toward and explore threat. In a subsequent activational phase, individuals avoid or, if avoidance is impossible, confront threat.

Delayed gratification.

An individual’s ability to abstain from a presently available reward in order to obtain a larger reward later. This ability depends on the extent to which an individual engages in temporal discounting.

Deoxyribonucleic acid.

Cellular storage system for genetic material. It comprises the body’s building instructions that organisms receive from their parent(s).

Depression.

In psychology/psychiatry, a mood disorder characterized by several symptoms, including increased sadness or lack of happiness. The symptoms need to be present for a period of two or more weeks.

Despair.

Term used to refer to a later stage of sadness, after individuals have lost hope. It is characterized by withdrawal.

Diencephalon.

Sits between the brainstem and the cerebrum. Its main components are the thalamus and the hypothalamus. Also called the interbrain.

Display rules.

Rules that govern emotional expression during communication. They are acquired during an individual’s lifetime and reflect internalized norms about what kinds of expressions are appropriate in what kinds of situations.

Distress.

Term used to refer to an initial stage of sadness, during which individuals attempt to restore something lost.

Dopamine.

Neurotransmitter that belongs to the monoamine and catecholamine families.

Dorsal.

Top or back of a structure.

Duchenne smile.

Type of smile named after its discoverer, Duchenne de Boulogne; also called a true smile. It involves both the mouth and the eye region. Posed smiles are often non-Duchenne in that they involve the mouth region only.

Ego-focused emotions.

Emotions that primarily concern the self and that are triggered by antecedents that are immediately relevant to the self. Original examples include anger and [Page 450]pride. Note, however, that these emotions may also concern others.

Electrocardiogram.

Measurement of the heart’s electrical activity.

Electroconvulsive therapy.

Treatment approach that uses an electric current to induce an epileptic seizure in patients with mental disorders such as depression and schizophrenia. Presumably, the treatment resets brain function. However, the exact treatment mechanisms are not yet understood.

Electrodermal measures.

Measures that record the activity of sweat glands in the skin. They comprise skin potentials, skin resistance, and skin conductance.

Electroencephalography.

Technique that uses surface electrodes to measure aspects of the brain’s electrical activity.

Embodied.

Term that describes the influence of bodily properties and states (e.g., leaning forward, being cold) on cognition.

Emotion prototypes.

Defined by Russell as best-exemplar emotions that are constructed from changes in core affect and a range of higher-order processes including appraisals, attributions, and subjective feelings.

Emotion regulation.

Mental process aimed to increase, maintain, or decrease the intensity, duration, or quality of an emotional experience. Emotion regulation comprises attentional deployment, cognitive change, and response modulation strategies.

Emotions.

Conscious or unconscious mental states elicited by events that are appraised as relevant for one’s needs and that motivate behaviors to fulfill these needs.

Encoding.

Mental process during which external or self-generated information is represented by sensory and association areas in the brain and maintained in short-term or working memory.

Enzymes.

Complex proteins that produce chemical reactions with other substances. In the context of the synapse, enzymes exist that help disintegrate superfluous neurotransmitters.

Epinephrine.

Neurotransmitter that belongs to the monoamine and catecholamine families. It is synthesized from norepinephine. See adrenaline.

Epigenetic mechanisms.

Mechanisms that regulate the transcription of DNA. They involve the modification of information that is stored together with the DNA in a cell’s nucleus. The word epigenetic is comprised of two parts: epi- and genetic. Epi- is a prefix of Greek origin, meaning “upon.” Together with the word genetic, it refers to processes acting upon genes.

Epilepsy.

Neurological disorder with recurrent episodes of excessive or hypersynchronous neuronal activity. Patients may experience sensory disturbances, a loss of consciousness, or motor spasms, among other things.

Essential amino acid.

Amino acid that is needed for the normal functioning of the body but that is not synthesized within the body itself. Instead, it must be obtained from food.

Event-related heart rate.

Measure that indicates the heart rate change caused by a particular event (e.g., an emotional stimulus). Most events first slow down and then speed up the heart. Moreover, these changes are typically enhanced when events are emotionally arousing.

Evolution.

Derives from the Latin word evolvo, which means to “unfurl” or “extricate.” Darwin used the term to describe how species emerge and change as a function of environmental conditions.

Evolutionary anthropology.

Study of humankind as focused on evolution and biology.

Experience sampling method.

Method in which participants are contacted (e.g., through a digital device) several times a day over the [Page 451]course of several days while pursuing their normal activities. Each time they are contacted, they must describe their current state (e.g., what they are doing, where they are, whom they are with, how they feel).

Explicit emotion processing.

Occurs when individuals consciously evaluate the emotional significance of a stimulus.

Explicit or declerative memories.

Memories that can be verbalized and that typically require effortful processing both during memory storage and retrieval.

Extinction (learning).

Process during which a previously conditioned response is extinguished or unlearned. For extinction to occur, a conditioned stimulus must be presented without its unconditioned stimulus (classical conditioning) or a conditioned behavior must no longer produce a previously associated reward or punishment (operant conditioning). After a number of trials, the individual will stop responding to the conditioned stimulus or stop showing the conditioned behavior.

Extinction (perception).

Phenomenon observed in patients with hemispatial neglect. When presented with one object in each side of the visual field, patients typically fail to perceive the object in contralesional space.

Facial Action Coding System.

System developed by Ekman and Friesen, who identified several action units (e.g., raising of inner eyebrows) that can be used to analyze facial expressions.

Familiarity.

Mental state resulting from incomplete memory retrieval. An individual remembers encountering a particular object/event before but has no or little additional information (e.g., location, time).

Fear.

Emotion elicited by stimuli that forecast a need and toward which an individual feels powerless.

Fear module.

Structure that plays a specific role for fear. Some researchers consider the amygdala a fear module.

5-HT transporter gene.

Gene that codes for the production of a membrane protein that removes 5-HT from the synapse by transporting it back into the presynaptic neuron. In the human genome, the gene comes in a long and a short variant.

5-hydroxytryptamine.

Neurotransmitter of the monoamine family. Also called serotonin.

Flashbulb memories.

Memories of events with great emotional significance. They are believed to differ from ordinary memories in that they are particularly vivid.

Flow.

Term used by Mihaly Csikszentmihalyi to describe a positive state of complete immersion into an activity or task.

Follicular phase.

Phase that spans across the first two weeks of the menstrual cycle, during which the woman menstruates and her follicles and their content, the egg, mature.

Forebrain.

Term that refers to the part of the central nervous system that sits before the midbrain/mesencephalon. It is composed of diencephalon and cerebrum.

Freezing.

Term that refers to an inhibition of movement that is caused by the perception of threat.

Frontotemporal dementia.

Form of dementia in which frontal and temporal cortex deteriorate. Patients undergo personality changes and become emotionally blunted.

Gametes.

Cells that enable sexual reproduction. They are typically referred to as sperm and eggs in males and females, respectively.

Gender.

Term that refers to differences between girls and boys, women and men that arise not from biological but from cultural/environmental factors. Gender and sex of a [Page 452]person do not always match. Some individuals may be biologically male or female but take on an opposite-sex gender identity.

Generalized anxiety disorder.

Disorder characterized by excessive worries about a wide range of commonplace events.

Genes.

The sections of DNA that form functional units responsible for a particular aspect of the body.

Glial cells.

Nervous system cells that support the function of neurons and that communicate with other cells through chemical pathways. Unlike neurons, they cannot communicate via action potentials.

Gliotransmitter.

Chemical messenger used by glial cells.

Globus pallidus.

Part of the basal ganglia, a subcortical gray-matter site. The globus pallidus sits medially of the striatum (i.e., more centrally within the brain).

Go/no-go task.

In such a task, participants see a series of stimuli, some of which are targets and others of which are nontargets. Participants must respond (e.g., by pushing a button) when they see a target and withhold their response when they see a nontarget.

Granule cell.

Type of neuron that can be found in the second and fourth layer of cortex as well as in other parts of the brain. Granule cells share a small size but are structurally and functionally diverse.

Gustatory cortex.

Primary sensory cortex for taste information. It is located in the dysgranular insula.

Heart-rate variability.

Range of heart periods that indicates how consistently or inconsistently the heart beats. Healthy hearts beat somewhat inconsistently.

Hebbian learning.

Term that refers to the synaptic changes thought to underpin memory formation. It is commonly paraphrased as “neurons that fire together, wire together.”

Hemispatial neglect.

Neurological syndrome arising from damage to brain tissue responsible for attention. Tissue damage is typically located in right parietal cortex. Hemispatial neglect patients show difficulties perceiving and attending to objects located in contralesional space.

Hippocampus.

Elongated structure situated in the medial temporal lobe. Its name stems from the Greek words hippos for “horse” and kampos for “sea monster,” and reflects the fact that the shape of the hippocampus resembles that of a sea horse.

Hormones.

Chemical messengers that are released by glands or other bodily tissue into the bloodstream.

Humor.

A bodily fluid in Galen’s theory of the body. He assumed that humors determined a person’s temperament.

Hypothalamus.

Subcortical structure that forms part of the diencephalon and that is situated below the thalamus.

Implicit Association Test.

Test that can be used to measure implicit affective or emotional responses to attitude objects such as insects, alcohol, and extramarital sex. The test probes the link between these objects and concepts of interest (e.g., positivity, pride, disgust) in an individual’s memory.

Implicit emotion processing.

Occurs when individuals perceive a stimulus and make no conscious attempts to evaluate its emotional significance. Any such processing occurs spontaneously and possibly unconsciously.

Implicit or procedural memories.

Memories that are difficult or impossible to verbalize. They may be stored and retrieved automatically.

Imprinting.

[Page 453]A form of attachment formation observed in the offspring of birds. During a few hours after hatching, chicks of many species will treat the first moving object they see as their mother.

Insula.

Small stretch of cortical tissue located below frontal, temporal, and parietal cortex.

International affective picture system.

Stimulus system that comprises a range of pictures that vary with respect to valence and arousal. The IAPS is often used as a means to modulate affect in research participants.

Joy.

Emotion elicited by the unexpected prospect of a reward.

Lamarckian theory.

Evolution theory developed by Jean-Baptiste Lamarck (1744–1829), according to which parents were able to pass on characteristics they had acquired during their lifetime. For example, children might be better at learning to play a particular instrument if their parents had already acquired that skill. As Darwin’s theory of evolution gained popularity, Lamarck’s theory received much critique. In the end, however, we find truth in both accounts, as nature conveniently combines genetic and experiential mechanisms of inheritance.

Lateral.

Outer sides of a structure.

Law of effect.

Law formulated by Thorndike that underpins operant conditioning. It refers to the fact that behaviors with positive consequences tend to be repeated, whereas behaviors with negative consequences tend to be avoided.

Learned helplessness.

Concept developed by Seligman and colleagues to refer to a condition in which humans and other animals have learned that they cannot avert a negative event. As a consequence of such learning, they will remain impassive when faced with the event.

Level of processing.

Concept developed within cognitive psychology to explain memory performance differences caused by different levels of engagement with to-be-remembered material. A deeper level of processing is associated with better memory performance than a shallow level of processing. In analogy, the feeling of an emotion may depend on the level of processing an emotion-eliciting event.

Limbic.

Term derived from the Latin word limbus, which means “rim” or “edge.” It was used by MacLean to refer to a circular set of structures lining the inner walls of the two hemispheres and supposedly governing emotions.

Locus coeruleus.

Latin for “blue spot.” Denotes nucleus situated in the pons of the brainstem. It is the primary brain site for the synthesis of noradrenaline.

Long-term depression.

In neuroscience, this term refers to changes in the synapse that inhibit the communication between the pre- and postsynaptic neuron. The underlying processes may be similar to long-term potentiation but occur for lower firing frequencies. LTD keeps LTP in check and enables memory pruning.

Long-term potentiation.

In neuroscience, this term refers to changes in the synapse that optimize the communication between the pre- and postsynaptic neuron. Such optimization is thought to result from the simultaneous activity of both neurons. (“Neurons that fire together, wire together.”) LTP is thought to be a primary neuronal mechanism for learning.

Luteal phase.

Phase that spans across the second half of the menstrual cycle. At the beginning of the luteal phase, an egg is released for fertilization.

Magnetic resonance imaging.

Technique that measures the energy fluctuations of hydrogen [Page 454]protons. Energy differences arising from differences in blood oxygenation form the basis for functional magnetic resonance imaging (fMRI).

Major histocompatibility complex.

A class of molecules that present incompatible (i.e., foreign) proteins to immune cells for destruction. Genes that code for MHC molecules differ widely in the human genome.

Marshmallow test.

Paradigm developed by Mischel and colleagues to examine preschoolers’ capacity for delayed gratification. Kids must decide between an unpreferred sweet that is available now and a preferred sweet that is available later. The experimenter measures whether and how long kids hold out for the preferred sweet.

Mask.

Stimulus that serves to prevent conscious processing of a target stimulus. It precedes or follows a target and typically differs from the target in that it is viewed for a longer period of time and is therefore perceptually more salient.

Medial.

Middle of a structure.

Medial forebrain bundle.

Using electrical brain stimulation, Olds identified this structure as a pleasure center. It contains dopaminergic projections spanning from the ventral tegmental area to the forebrain.

Medial prefrontal cortex.

Brain structure located in the medial walls of the hemispheres, anteriorly from the central fissure. It surrounds the anterior cingulate cortex.

Mind-body problem.

Philosophical problem concerning the relation between mind and body. It is considered a problem because, intuitively, the mind seems immaterial and thus different from the body. However, the mind depends on the body and this dependence confounds the mind’s seemingly immaterial nature.

Mindfulness training.

Form of meditation in which individuals engage in metacognition, focusing on current bodily and mental states.

Mixed longitudinal design.

Method that combines cross-sectional and longitudinal data gathering by following individuals of different ages (e.g., young, middle-aged, old) across a few years.

Monoamineoxidase (MAO) inhibitors.

Drugs that inhibit the activity of MAO. Because MAO serves to breakdown superfluous neurotransmitters in the synapse, MAO-inhibitors reduce such breakdown and allow more neurotransmitters to act on postsynaptic receptors.

Monoamines.

Chemical messengers that contain one amino group. They comprise catecholamines and tryptamines.

Monogamous.

Term that characterizes species in which most individuals form selective pair bonds after mating to jointly care for offspring. Although these individuals are bonded, they may be sexually active outside their pair bond. Moreover, of the monogamous species, only a few stay within the same pair bond for more than one breeding season.

Mood.

Prolonged affective or emotional state for which there is no single eliciting event or the eliciting event is no longer present.

Multidimensional scaling.

Statistical procedure that helps illustrate the relationship or distance between items (e.g., emotions) in a multidimensional space.

Neocortex.

Refers to cortex that has six well-defined layers and that was originally thought to have evolved in higher mammals (e.g., primates). More recent research suggests that it was present in the earliest mammal.

Nervous system.

Comprises of nerve cells and enables organisms to represent the information [Page 455]that is necessary for them to usefully interact with their environment.

Neurons.

Cells that are capable of firing an action potential. They are considered the primary constituent of a nervous system.

Neuropeptides.

Chemical messengers that contain a protein and that are active within the brain.

Neurotransmitters.

Chemical messengers that are released by a presynaptic neuron and that influence the activity of a postsynaptic neuron.

Nociceptors.

Cells dedicated to the perception of pain.

Norepinephrine.

Neurotransmitter that belongs to the monoamine and catecholamine families. It is synthesized from dopamine. Also called noradrenaline,

Oddball procedure.

Procedure that involves the presentation of a rare stimulus intermixed with a frequent stimulus. In an active oddball procedure, participants detect the rare stimulus. In a passive oddball procedure, stimulus processing is monitored through online measures such as EEG or heart rate.

Online measures.

Physiological and brain imaging measures are referred to as online measures because they measure bodily and mental processes as they unfold in time.

Operant conditioning.

Form of learning whereby the consequences of an action determine how well this action is retained.

Opioids.

Chemical messengers that bind to opioid receptors. They are referred to as endogenous opioids if they are naturally produced within the body. Opioids can also be derived from poppy (i.e., opium) or they can be synthesized.

Orbicularis occuli.

Facial muscle that surrounds the eye and that makes the eye squint when activated.

Other-focused emotions.

Emotions that arise from antecedents with primary relevance for others or for the relationship that the individual has with them. Examples include shame and guilt.

Oxytocin.

Chemical messenger that acts as a hormone or peptide and as a neurotransmitter or neuropeptide. It has multiple functions, including the regulation of attachment and social behavior.

Paleomammalian brain.

Defined by Paul MacLean as a set of brain structures present in all mammals and supporting the limbic system.

Panic disorder.

Disorder characterized by the fearful anticipation and frequent experience of panic attacks. During these attacks individuals feel intense fear (e.g., death, loss of control) and show a range of bodily arousal symptoms.

Parahippocampal gyrus.

Gray-matter structure that surrounds the hippocampus.

Parallel evolution.

Describes instances in which two species share a characteristic because that characteristic was present in a common ancestor.

Parasympathetic nervous system.

One of two efferent strands of the autonomic nervous system. It is largely associated with conserving/restoring the body’s energy.

Pathogens.

Microorganisms such as bacteria or viruses that befall a host and can cause disease.

Peer review.

A system whereby research reports are reviewed for quality by scientists unconnected to the research. The reviewers may recommend alterations in the reports. Moreover, the reviewers’ comments may form the basis for editorial decisions regarding whether reports should be published.

Perceptual bottleneck.

Term that refers to the limited bandwidth of perceptual processing. [Page 456]When two or more objects reach an individual’s senses they compete for awareness. Objects that win this competition will receive better perceptual representation than will objects that lose this competition.

Peripheral nervous system.

Part of the nervous system that is distributed across the body and that serves to connect the central nervous system with peripheral sensors (e.g., skin receptors), effectors (e.g., muscles), and internal organs (e.g., heart).

Phenomenological approach.

Has a long tradition within philosophy. It is concerned with consciousness and the first-person experience of an object.

Pheromones.

Chemicals released by the body that influence the behavior of conspecifics.

Phobia.

Anxiety disorder in which patients experience debilitating fears of specific items such as spiders, heights, or enclosed spaces.

Phylogenetically.

Refers to the evolutionary relationship between species. A species that is phylogenetically older than another species evolved at an earlier point in history.

Pictures of facial affect.

Set of facial expressions posed by actors who were asked to portray different basic emotions. Also known as the “Ekman faces.”

Pineal gland.

Small endocrine structure located in the middle of the brain. Descartes considered it the point of contact between body and soul.

Pleasure center.

Set of dopaminergic structures identified by James Olds. Individuals perceive the activation of these structures as pleasurable.

Point Subtraction Aggression Paradigm.

Task that measures aggression implicitly. Participants have to trade off earning points by pushing a button with avenging points stolen by an alleged thief.

Positive and negative affect schedule.

Self-report instrument that measures both affect and emotion. It can be used as a state (how does an individual feel now) or a trait (how does an individual feel typically) measure.

Positive psychology.

Movement within psychology that stresses the importance of an individual’s positive characteristics and resources as a means to optimize mental functioning.

Positivity effect.

Term that refers to older adults’ propensity to disengage from negative and to engage with positive information.

Positron emission tomography.

Technique in which a radioactive tracer is injected into a person’s bloodstream. When used for neuroimaging, the tracer travels to the brain where its radionuclides emit positrons. The site of positron emission gives clues about the local availability of brain chemicals.

Posterior.

Back of a structure.

Precession.

Type of rotational movement whereby a rotating body moves its rotational axis. For example, the rotational axis may move in such a way that its movements describe a cone.

Preferential looking paradigm.

Method developed by Fantz (1964) to explore stimulus preferences in preverbal infants. Infants are presented with two stimuli and the duration of orientation to either stimulus is measured.

Premotor cortex.

Forms part of the frontal cortex; sits anterior to motor cortex.

Preparedness.

Term that refers to the fact that conditioning depends on species-specific biological predispositions that make some stimulus-stimulus or stimulus-response contingencies more relevant for learning than others.

Primary affects.

[Page 457]Fundamental feeling states that differ qualitatively, with each state having their own function. Term used by Tomkins.

Principal component analysis.

Statistical technique that helps reduce a large number of variables into a smaller set of principal components. The first component produced with this technique explains most of the data, and the contribution of each following component will be weaker and weaker. Researchers decide which components to consider “principal” based on the components’ explanatory power.

Problem-based coping.

Behavioral coping strategy aimed at improving one’s situation by reducing the problem or stressor. Problem-based coping can be dissociated from appraisal or emotion-focused coping, which tackle thoughts and feelings instead.

Prospect theory.

Theory developed by Kahneman and Tversky that provides a framework for the psychological processes underlying decision making.

Prototype.

Mental representation of the average member of a category. Prototypes help categorize novel instances based on similarity to the prototype.

Psyche.

Word that derives from the Greek word psukhē, meaning breath, life, or soul.

QRS complex.

Prominent wave pattern in the electrocardiogram that comprises three waves referred to as Q, R, and S waves, respectively, by the Dutch physiologist William Einthoven. The QRS complex represents the depolarization of the heart’s ventricles.

Readiness potential.

Deflection in the event-related potential that emerges over motor cortex in the hemisphere opposite to that of an ensuing motor response. It reflects the preparation of this response.

Receptive field.

Term that refers to the property of a sensory neuron. An external stimulus that influences the likelihood of an action potential is said to fall within the neuron’s receptive field.

Recollection.

Mental state resulting from complete memory retrieval. An individual has access to critical object/event information such as when the object/event was encountered and what the individual did at the time.

Reconsolidation.

Process that helps restabilize a previously recalled memory through protein synthesis in relevant memory structures.

Remission rate.

Reflects the number of treated patients who experience a temporary relief from symptoms. It is understood that these symptoms may return at a later point. Remission rate differs from the rate of cured patients in which symptoms do not return.

Response-focused emotion regulation.

Emotion regulation strategy that tackles the output of a putative emotion system.

Retrieval.

Mental process during which information previously stored in long-term memory is accessed and made available to working memory. Depending on how completely information is retrieved, individuals may have a feeling of familiarity or knowing only, or they may be able to recollect a complete memory.

Reward prediction error.

Error that results when a reward comes unexpectedly or an expected reward fails to materialize. The brain represents such errors and uses them for learning.

Sadness.

Emotion elicited to negative events that allow little opportunity for problem-based coping and that directly or indirectly produce some sort of social loss. Sadness has an initial stage of distress that may be followed by a stage of despair.

Scalar timing theory.

[Page 458]Theory developed by John Gibbon and colleagues that outlines a psychological mechanism for time perception.

Sclerosis.

Hardening of bodily tissue that is typically associated with reduced tissue functionality.

Selective serotonin reuptake inhibitors.

Class of drugs used to treat clinical depression. They act by preventing serotonin from re-entering the presynaptic neuron and thus effectively increase serotonin availability in the synapse.

Self-actualization.

Term that refers to the highest-order need in Maslow’s pyramid of needs. Individuals fulfill this need if they are able to realize their full potential and achieve all they can possibly achieve.

Self-construal.

Concept in social psychology relating to how individuals define themselves. It is typically applied in the context of cultural comparisons, where self-construal can be independent or interdependent.

Self-reference effect.

Phenomenon in which individuals remember self-relevant information better than information that is not self-relevant.

Sentience.

Awareness of one’s mental and bodily state.

Serotonin.

Neurotransmitter that belongs to the monoamine and tryptamine families. It is synthesized from tryptophan.

Sexual dimorphism.

Structural difference between the two sexes (e.g., height, genitals).

Sham-rage.

Excited state caused by slight provocation in an animal after cortex has been surgically removed.

Single nucleotide polymorphism.

A position in a gene for which individuals differ in a single base pair.

Socioemotional selectivity theory.

Theory developed by Carstensen and colleagues to explain emotional changes in aging. It holds that a shortening life expectancy alters how individuals engage with emotional events in their environment. With less time left, emphasis shifts from the future to the “here and now,” away from negative and toward positive emotions.

Socratic thinking.

Method developed by Socrates whereby he used questions and dialogues to achieve knowledge and insight.

Somatic marker hypothesis.

Hypothesis formulated by Antonio Damasio. It holds that feedback of emotion-induced bodily processes influences decision making.

Spontaneous recovery.

Recovery of a conditioned response after this response was extinguished. For example, a fear-conditioned tone loses its power to provoke fear when it is repeatedly presented alone. If, subsequently, the tone is withheld (e.g., for a day) and then presented again, it can spontaneously trigger the old fear response without the need for additional conditioning.

Startle reflex.

Reflex that is triggered by a sudden sensory change. It involves muscle contractions that start at the head and move through the body. It is considered a defensive response.

Stereotype threat.

Phenomenon experienced by individuals who engage in activities for which they know that members of their group typically perform poorly. This knowledge, or the activated stereotype, hampers their performance.

Stoic school.

Emerged during the Hellenistic period of ancient Greece. Its name derives from the Greek word stoa, meaning “collonade.” One of its tenets was that emotions should be controlled.

Striatal beat-frequency model.

[Page 459]Model proposed by Buhushi and Meck. It pins time perception to the striatum and its connections to the frontal cortex. The striatum is thought to regulate and monitor oscillations in frontal cortex activity.

Striatum.

Part of the basal ganglia, a subcortical gray-matter site. The striatum is comprised of the putamen and the caudate nucleus, and it has a striped appearance.

Stroop task.

Cognitive interference task developed by John Ridley Stroop in 1935. Participants must name the ink color of color words printed with congruous or incongruous ink (e.g., blue printed in blue and green).

Subliminally.

In a subliminal stimulus presentation, participants cannot fully perceive the stimulus. Images may be flashed and/or followed by a masking stimulus to prevent proper recognition. Sounds may be played just below hearing threshold. Such presentations are made to explore unconscious aspects of stimulus processing.

Sympathetic nervous system.

One of two efferent strands of the autonomic nervous system. This system is largely associated with mobilizing the body for action.

Synapses.

Points of communication between two neurons. Synapses are formed between the axon terminal of one neuron and the membrane (typically at the dendrite) of another neuron. It is where neutransmitters are released and bind to receptors of the postsynaptic neuron.

Taxon.

In biology, refers to a group of individuals such as a species.

Temporal discounting.

Phenomenon whereby individuals discount the value of rewards the longer the time that elapses until they receive the reward.

Tend-and-befriend response.

Alternative to the fight-or-flight response to threat. It refers to threat-induced affiliative behaviors directed at creating or maintaining social bonds that are reproductively important (e.g., caring for offspring) or that may aid in times of need (e.g., relatives, allies).

Thalamus.

Subcortical structure (i.e., below cortex and white matter) that forms part of the diencephalon. It receives input from all the senses except olfaction. It is a key player in Cannon’s emotion theory.

Theories.

Frameworks of ideas that help understand or explain a particular phenomenon. They can be based on speculation, logical inferences, and/or empirical data. Researchers can use a theory to make predictions that they then test in an experiment.

Theory of Mind.

Mental capacity for recognizing that others have minds of their own and for understanding these minds.

Tonic changes.

In the context of neural activity, tonic changes refer to changes in firing patterns that are sustained for several seconds or more. They differ from phasic changes in that they extend over a longer time frame.

Top-down.

Term that describes mental processes arising from an intention or goal activated in working memory. The goal relevance of a particular stimulus for the individual is said to influence attentional selection via top-down processes.

Total peripheral resistance.

Blood pressure measure that takes into account both arterial and venous pressure. It was shown to differentiate fear and anger.

Transcranial magnetic stimulation (TMS).

Stimulation that uses a magnetic coil to produce an electric current that interferes with and modulates normal brain function.

Transporters.

[Page 460]In the context of a synapse, transporters are a type of protein located within the membrane of the presynaptic neuron. Transporters move superfluous neurotransmitters back into the cell.

Tricyclic antidepressants.

Drugs that have a three-ringed molecular structure and are used to treat clinical depression. They block the reuptake of monoamines into the presynaptic neuron.

Tryptophan.

Essential amino acid that forms part of most proteins and serves as a precursor for 5-HT.

Turner syndrome.

Genetic defect in which girls have only one fully intact X chromosome. The defect causes a range of dysfunctions that are both physical (e.g., webbed neck, sterility) and mental (e.g., memory).

Unconditioned stimuli.

Stimuli that elicit an innate response such as an emotion.

Universal antecedent.

Stimulus or event that reliably causes an emotion across individuals and cultures.

Vagus nerve.

The tenth cranial nerve. It connects the brain with the body’s internal organs.

Valence.

Refers to the affective value of a stimulus along a dimension, with good and bad or positive and negative as polar opposites.

Ventral.

Bottom or front of a structure.

Vicarious learning.

Occurs when an individual acquires a response (e.g., emotion) to a stimulus based on observing another individual’s encounter with that stimulus.

Viscera.

The body’s internal organs.

Vomeronasal organ.

Part of the olfactory system that serves primarily the perception of pheromones.

Von Economo neurons.

Large neurons with a spindle-shaped soma from which only two dendrites protrude in opposite directions. They are found only in large-brained species. Named after one of their discoverers, Constantin von Economo.

White matter.

Nerve tissue comprising myelinated axons. The cerebrum’s white matter is situated between the basal ganglia and the cortex.

World Medical Association.

An international body concerned with developing and preserving high ethical standards in medicine worldwide.

Zygomaticus major.

Facial muscle located around the mouth that, when activated, draws the mouth corners backward.