Vocabulary

5α-reductase: An enzyme required to convert testosterone to 5α-dihydrotestosterone.
Ablation: Surgical removal of brain tissue.
Action potential: A transient all-or-nothing electrical current that is conducted down the axon when the membrane potential reaches the threshold of excitation.
Action Potential: A transient all-or-nothing electrical current that is conducted down the axon when the membrane potential reaches the threshold of excitation.
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.
Aggression: A form of social interaction that includes threat, attack, and fighting.
Agonists: A drug that increases or enhances a neurotransmitter’s effect.
Alogia: A reduction in the amount of speech and/or increased pausing before the initiation of speech.
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.
Amygdala: Two almond-shaped structures located in the medial temporal lobes of the brain.
Anhedonia/amotivation: A reduction in the drive or ability to take the steps or engage in actions necessary to obtain the potentially positive outcome.
Antagonist: A drug that blocks a neurotransmitter’s effect.
Aromatase: An enzyme that converts androgens into estrogens.
Autobiographical memory: Memory for the events of one’s life.
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.
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.
Axon: Part of the neuron that extends off the soma, splitting several times to connect with other neurons; main output of the neuron.
Basal ganglia: Subcortical structures of the cerebral hemispheres involved in voluntary movement.
Behavioral genetics: The empirical science of how genes and environments combine to generate behavior.
Blood Alcohol Content (BAC): Blood Alcohol Content (BAC): a measure of the percentage of alcohol found in a person’s blood. This measure is typically the standard used to determine the extent to which a person is intoxicated, as in the case of being too impaired to drive a vehicle.
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.
Brain Stem: The “trunk” of the brain comprised of the medulla, pons, midbrain, and diencephalon.
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.
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 Nervous System: The portion of the nervous system that includes the brain and spinal cord.
Cerebellum: The distinctive structure at the back of the brain, Latin for “small brain.”
Cerebellum: The distinctive structure at the back of the brain, Latin for “small brain.”
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: Usually refers to the cerebral cortex and associated white matter, but in some texts includes the subcortical structures.
Chromosomal sex: The sex of an individual as determined by the sex chromosomes (typically XX or XY) received at the time of fertilization.
Circadian Rhythm: Circadian Rhythm: The physiological sleep-wake cycle. It is influenced by exposure to sunlight as well as daily schedule and activity. Biologically, it includes changes in body temperature, blood pressure and blood sugar.
Consciousness: Consciousness: the awareness or deliberate perception of a stimulus
Consolidation: The process occurring after encoding that is believed to stabilize memory traces.
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).
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).
Converging evidence: Similar findings reported from multiple studies using different methods.
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.
Corpus Callosum: The thick bundle of nerve cells that connect the two hemispheres of the brain and allow them to communicate.
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.
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.
Cues: Cues: a stimulus that has a particular significance to the perceiver (e.g., a sight or a sound that has special relevance to the person who saw or heard it)
Defeminization: The removal of the potential for female traits.
Delusions: False beliefs that are often fixed, hard to change even in the presence of conflicting information, and often culturally influenced in their content.
Demasculinization: The removal of the potential for male traits.
Dendrite: Part of a neuron that extends away from the cell body and is the main input to the neuron.
Dendrites: 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.
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.
Depressants: Depressants: a class of drugs that slow down the body’s physiological and mental processes.
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).
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.
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.
Dihydrotestosterone (DHT): A primary androgen that is an androgenic steroid product of testosterone and binds strongly to androgen receptors.
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.
Dissociation: Dissociation: the heightened focus on one stimulus or thought such that many other things around you are ignored; a disconnect between one’s awareness of their environment and the one object the person is focusing on
Distinctiveness: The principle that unusual events (in a context of similar events) will be recalled and recognized better than uniform (nondistinctive) events.
DNA methylation: Covalent modifications of mammalian DNA occurring via the methylation of cytosine, typically in the context of the CpG dinucleotide.
DNA methyltransferases (DNMTs): Enzymes that establish and maintain DNA methylation using methyl-group donor compounds or cofactors. The main mammalian DNMTs are DNMT1, which maintains methylation state across DNA replication, and DNMT3a and DNMT3b, which perform de novo methylation.
Dopamine: A neurotransmitter in the brain that is thought to play an important role in regulating the function of other neurotransmitters.
Drive state: Affective experiences that motivate organisms to fulfill goals that are generally beneficial to their survival and reproduction.
Electroencephalogram: A measure of electrical activity generated by the brain’s neurons.
Electroencephalography (EEG): A neuroimaging technique that measures electrical brain activity via multiple electrodes on the scalp.
Electroencephalography (EEG): A neuroimaging technique that measures electrical brain activity via multiple electrodes on the scalp.
Electrostatic pressure: The force on two ions with similar charge to repel each other; the force of two ions with opposite charge to attract to one another.
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.
Endocrine gland: A ductless gland from which hormones are released into the blood system in response to specific biological signals.
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.
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.
Epigenetics: Heritable changes in gene activity that are not caused by changes in the DNA sequence. http://en.wikipedia.org/wiki/Epigenetics
Epigenetics: The study of heritable changes in gene expression or cellular phenotype caused by mechanisms other than changes in the underlying DNA sequence. Epigenetic marks include covalent DNA modifications and posttranslational histone modifications.
Epigenome: The genome-wide distribution of epigenetic marks.
Episodic memory: The ability to learn and retrieve new information or episodes in one’s life.
Episodic memory: Memory for events in a particular time and place.
Estrogen: Any of the C18 class of steroid hormones, so named because of the estrus-generating properties in females. Biologically important estrogens include estradiol and estriol.
Euphoria: Euphoria: an intense feeling of pleasure, excitement or happiness.
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.
Excitatory postsynaptic potentials: A depolarizing postsynaptic current that causes the membrane potential to become more positive and move towards the threshold of excitation.
Feminization: The induction of female traits.
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.
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.
Flexible Correction Model: Flexible Correction Model: the ability for people to correct or change their beliefs and evaluations if they believe these judgments have been biased (e.g., if someone realizes they only thought their day was great because it was sunny, they may revise their evaluation of the day to account for this “biasing” influence of the weather)
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 front most (anterior) part of the cerebrum; anterior to the central sulcus and responsible for motor output and planning, language, judgment, and decision-making.
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 (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): 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.
Gene: A specific deoxyribonucleic acid (DNA) sequence that codes for a specific polypeptide or protein or an observable inherited trait.
Genome-wide association study (GWAS): A study that maps DNA polymorphisms in affected individuals and controls matched for age, sex, and ethnic background with the aim of identifying causal genetic variants.
Genotype: The DNA content of a cell’s nucleus, whether a trait is externally observable or not.
Gonadal sex: The sex of an individual as determined by the possession of either ovaries or testes. Females have ovaries, whereas males have testes.
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.
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).
Hallucinogens: Hallucinogens: substances that, when ingested, alter a person’s perceptions, often by creating hallucinations that are not real or distorting their perceptions of time.
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.
Histone acetyltransferases (HATs) and histone deacetylases (HDACs): HATs are enzymes that transfer acetyl groups to specific positions on histone tails, promoting an “open” chromatin state and transcriptional activation. HDACs remove these acetyl groups, resulting in a “closed” chromatin state and transcriptional repression.
Histone modifications: Posttranslational modifications of the N-terminal “tails” of histone proteins that serve as a major mode of epigenetic regulation. These modifications include acetylation, phosphorylation, methylation, sumoylation, ubiquitination, and ADP-ribosylation.
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.
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.
Hormone: An organic chemical messenger released from endocrine cells that travels through the blood to interact with target cells at some distance to cause a biological response.
Hormones: Chemicals released by cells in the brain or body that affect cells in other parts of the brain or body.
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.
Hypnosis: Hypnosis: the state of consciousness whereby a person is highly responsive to the suggestions of another; this state usually involves a dissociation with one’s environment and an intense focus on a single stimulus, which is usually accompanied by a sense of relaxation
Hypnotherapy: Hypnotherapy: The use of hypnotic techniques such as relaxation and suggestion to help engineer desirable change such as lower pain or quitting smoking.
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 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: A brain structure located below the thalamus and above the brain stem.
Identical twins: Two individual organisms that originated from the same zygote and therefore are genetically identical or very similar. The epigenetic profiling of identical twins discordant for disease is a unique experimental design as it eliminates the DNA sequence-, age-, and sex-differences from consideration.
Implicit Associations Test: Implicit Associations Test (IAT): A computer reaction time test that measures a person’s automatic associations with concepts. For instance, the IAT could be used to measure how quickly a person makes positive or negative evaluations of members of various ethnic groups.
Ingroup: A social group to which an individual identifies or belongs.
Inhibitory postsynaptic potentials: A hyperpolarizing postsynaptic current that causes the membrane potential to become more negative and move away from the threshold of excitation.
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.
Jet Lag: Jet Lag: The state of being fatigued and/or having difficulty adjusting to a new time zone after traveling a long distance (across multiple time zones).
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.
Lesions: Abnormalities in the tissue of an organism usually caused by disease or trauma.
Lesions: Damage or tissue abnormality due, for example, to an injury, surgery, or a vascular problem.
Limbic system: Includes the subcortical structures of the amygdala and hippocampal formation as well as some cortical structures; responsible for aversion and gratification.
Limbic System: Includes the subcortical structures of the amygdala and hippocampal formation as well as some cortical structures; responsible for aversion and gratification.
Lordosis: A physical sexual posture in females that serves as an invitation to mate.
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.
Masculinization: The induction of male traits.
Maternal behavior: Parental behavior performed by the mother or other female.
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.
Melatonin: Melatonin: A hormone associated with increased drowsiness and sleep.
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.
Metabolism: Breakdown of substances.
Metabolite: A substance necessary for a living organism to maintain life.
Mindfulness: Mindfulness: a state of heightened focus on the thoughts passing through one’s head, as well as a more controlled evaluation of those thoughts (e.g., do you reject or support the thoughts you’re having?)
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.
Motor cortex: Region of the frontal lobe responsible for voluntary movement; the motor cortex has a contralateral representation of the human body.
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.
Myelin Sheath: Fatty tissue, that insulates the axons of the neurons; myelin is necessary for normal conduction of electrical impulses among neurons.
Nervous System: The body’s network for electrochemical communication. This system includes all the nerves cells in the body.
Neural plasticity: The ability of synapses and neural pathways to change over time and adapt to changes in neural process, behavior, or environment.
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.
Neurons: Individual brain cells
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.
Neurotransmitter: A chemical messenger that travels between neurons to provide communication. Some neurotransmitters, such as norepinephrine, can leak into the blood system and act as hormones.
Neurotransmitters: Chemical substance released by the presynaptic terminal button that acts on the postsynaptic cell.
Neurotransmitters: Chemical substance released by the presynaptic terminal button that acts on the postsynaptic cell.
Nomenclature: Naming conventions.
Noninvasive procedure: A procedure that does not require the insertion of an instrument or chemical through the skin or into a body cavity.
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.
Occipital lobe: The back most (posterior) part of the cerebrum; involved in vision.
Occipital Lobe: The back most (posterior) part of the cerebrum; involved in vision.
Orbital frontal cortex: A region of the frontal lobes of the brain above the eye sockets.
Outgroup: A social group to which an individual does not identify or belong.
Oxygenated hemoglobin: Hemoglobin carrying oxygen.
Oxytocin: A nine amino acid mammalian neuropeptide. Oxytocin is synthesized primarily in the brain, but also in other tissues such as uterus, heart and thymus, with local effects. Oxytocin is best known as a hormone of female reproduction due to its capacity to cause uterine contractions and eject milk. Oxytocin has effects on brain tissue, but also acts throughout the body in some cases as an antioxidant or anti-inflammatory.
Oxytocin: A peptide hormone secreted by the pituitary gland to trigger lactation, as well as social bonding.
Parasympathetic nervous system (PNS): One of the two major divisions of the autonomic nervous system, responsible for stimulation of “rest and digest” activities.
Parental behavior: Behaviors performed in relation to one’s offspring that contributes directly to the survival of those offspring
Parietal Lobe: The part of the cerebrum between the frontal and occipital lobes; involved in bodily sensations, visual attention, and integrating the senses.
Parietal lobe: The part of the cerebrum between the frontal and occipital lobes; involved in bodily sensations, visual attention, and integrating the senses.
Paternal behavior: Parental behavior performed by the father or other male.
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.
Peripheral Nervous System: All of the nerve cells that connect the central nervous system to all the other parts of the body.
Pharmacokinetics: The action of a drug through the body, including absorption, distribution, metabolism, and excretion.
Phenotype: The pattern of expression of the genotype or the magnitude or extent to which it is observably expressed—an observable characteristic or trait of an organism, such as its morphology, development, biochemical or physiological properties, or behavior.
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.
Polypharmacy: The use of many medications.
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 (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.
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.
Preoptic area: A region in the anterior hypothalamus involved in generating and regulating male sexual behavior.
Preoptic region: A part of the anterior hypothalamus.
Priming: Priming: the activation of certain thoughts or feelings that make them easier to think of and act upon
Processing speed: The speed with which an individual can perceive auditory or visual information and respond to it.
Progesterone: A primary progestin that is involved in pregnancy and mating behaviors.
Progestin: A class of C21 steroid hormones named for their progestational (pregnancy-supporting) effects. Progesterone is a common progestin.
Prohormone: A molecule that can act as a hormone itself or be converted into another hormone with different properties. For example, testosterone can serve as a hormone or as a prohormone for either dihydrotestosterone or estradiol.
Prolactin: A protein hormone that is highly conserved throughout the animal kingdom. It has many biological functions associated with reproduction and synergistic actions with steroid hormones.
Psychoactive drugs: A drug that changes mood or the way someone feels.
Psychopathology: Illnesses or disorders that involve psychological or psychiatric symptoms.
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.).
Quantitative genetics: Scientific and mathematical methods for inferring genetic and environmental processes based on the degree of genetic and environmental similarity among organisms.
Receptor: A chemical structure on the cell surface or inside of a cell that has an affinity for a specific chemical configuration of a hormone, neurotransmitter, or other compound.
Recoding: The ubiquitous process during learning of taking information in one form and converting it to another form, usually one more easily remembered.
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: 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.
Reward value: A neuropsychological measure of an outcome’s affective importance to an organism.
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.
Satiation: The state of being full to satisfaction and no longer desiring to take on more.
Semantic memory: The more or less permanent store of knowledge that people have.
Sex determination: The point at which an individual begins to develop as either a male or a female. In animals that have sex chromosomes, this occurs at fertilization. Females are XX and males are XY. All eggs bear X chromosomes, whereas sperm can either bear X or Y chromosomes. Thus, it is the males that determine the sex of the offspring.
Sex differentiation: The process by which individuals develop the characteristics associated with being male or female. Differential exposure to gonadal steroids during early development causes sexual differentiation of several structures including the brain.
Simulation: Imaginary or real imitation of other people’s behavior or feelings.
Social brain: The set of neuroanatomical structures that allows us to understand the actions and intentions of other people.
Social categorization: The act of mentally classifying someone into a social group (e.g., as female, elderly, a librarian).
Social support: A subjective feeling of psychological or physical comfort provided by family, friends, and others.
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.
Soma: Cell body of a neuron that contains the nucleus and genetic information, and directs protein synthesis.
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.
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.
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.
Spatial resolution: The degree to which one can separate a single object in space from another.
Spines: Protrusions on the dendrite of a neuron that form synapses with terminal buttons of the presynaptic axon.
Split-brain patient: A patient who has had most or all of his or her corpus callosum severed.
Split-brain Patient: A patient who has had most or all of his or her corpus callosum severed.
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.
Stimulants: Stimulants: a class of drugs that speed up the body’s physiological and mental processes.
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.
Subcortical: Structures that lie beneath the cerebral cortex, but above the brain stem.
Sulci: (plural) Grooves separating folds of the cortex.
Sulcus: A groove separating folds of the cortex.
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.
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 (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.
Synapses: Junction between the presynaptic terminal button of one neuron and the dendrite, axon, or soma of another postsynaptic neuron.
Synaptic gap: Also known as the synaptic cleft; the small space between the presynaptic terminal button and the postsynaptic dendritic spine, axon, or soma.
Synaptic 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.
Target cell: A cell that has receptors for a specific chemical messenger (hormone or neurotransmitter).
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 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.
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.
Terminal button: The part of the end of the axon that form synapses with postsynaptic dendrite, axon, or soma.
Testosterone: The primary androgen secreted by the testes of most vertebrate animals, including men.
Thalamus: A structure in the midline of the brain located between the midbrain and the cerebral cortex.
Threshold of excitation: Specific membrane potential that the neuron must reach to initiate an action potential.
Trance States: Trance: a state of consciousness characterized by the experience of “out-of-body possession,” or an acute dissociation between one’s self and the current, physical environment surrounding them.
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.
Transverse plane: See “horizontal plane.”
Twin studies: A behavior genetic research method that involves comparison of the similarity of identical (monozygotic; MZ) and fraternal (dizygotic; DZ) twins.
Vagus nerve: The 10th cranial nerve. The mammalian vagus has an older unmyelinated branch which originates in the dorsal motor complex and a more recently evolved, myelinated branch, with origins in the ventral vagal complex including the nucleus ambiguous. The vagus is the primary source of autonomic-parasympathetic regulation for various internal organs, including the heart, lungs and other parts of the viscera. The vagus nerve is primarily sensory (afferent), transmitting abundant visceral input to the central nervous system.
Vasopressin: A nine amino acid mammalian neuropeptide. Vasopressin is synthesized primarily in the brain, but also may be made in other tissues. Vasopressin is best known for its effects on the cardiovascular system (increasing blood pressure) and also the kidneys (causing water retention). Vasopressin has effects on brain tissue, but also acts throughout the body.
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.
Voltage: The difference in electric charge between two points.
White matter: The inner whitish regions of the cerebrum comprised of the myelinated axons of neurons in the cerebral cortex.
Working memory: The ability to maintain information over a short period of time, such as 30 seconds or less.