Glossary
Abuse.
In addiction the use of drugs which leads to problems for the individual.
Acetylcholine.
A neurotransmitter that acts at nicotine receptors.
Action potential.
Sometimes called a nerve impulse or spike. It is the explosion of electrical activity that is created by a depolarizing current as a result of a change in the cellular membrane and the movement of ions inside and outside of the cell.
ADD.
Attention Deficit Disorder.
Adderall.
Brand name for mixed amphetamine/dextroamphetamine. A medication used to treat ADHD. It increases dopamine and noradrenaline at the synapse.
Addiction.
The extreme or psychopathological state where control over drug use is lost.
ADHD-C.
From DSM-IV criteria – a subtype of ADHD called the combined type which is a combination of ADHD-H and ADHD-I.
ADHD-H.
From DSM-IV criteria – a subtype of ADHD with predominantly hyperactive/impulsivity symptoms.
ADHD-I.
From DSM-IV criteria – a subtype of ADHD with predominantly inattentive symptoms.
Agonists.
In pharmacology, a drug that acts on a neural system to facilitate a response.
Allele.
An alternative form of a gene (one of a pair) that is located at a specific position on a specific chromosome, e.g. the different types of DRD4 genes.
Amphetamine.
A psychostimulant drug used in the treatment of ADHD. It increases the amount of dopamine in the synapse.
Amygdala.
The almond-shaped group of nuclei involved in emotions.
Anemia.
A condition that occurs when there is a reduced number of red blood cells or concentration of hemoglobin. The most common cause is an iron deficiency.
Animal model.
The use of an animal to mimic part or all of a human disorder or disease, e.g. the SHR model of ADHD.
Anoxia.
A condition characterized by an absence of oxygen supply to an organ or a tissue.
Anterior cingulate cortex.
The frontal part of the cingulate cortex. It is involved in controlling numerous cognitive functions.
Atomoxetine.
(Brand name Strattera.) A non-stimulant medication for ADHD that is a noradrenergic reuptake blocker. It increased the levels of noradrenaline at the synapse.
Attention Deficit Hyperactivity Disorder (ADHD).
The current name used in the DSM-IV for the collection of symptoms that are inattention, impulsivity, and hyperactivity. Compare with Hyperkinetic Disorder (HKD) from the ICD-10.
Attentional blink paradigm.
A measure of attention and focus in which two targets are visually displayed in rapid serial succession and people cannot identify the second target. It is as though the mind’s eye must “blink” in order to attend to two temporally distinct meaningful items.
Automaticity.
A cognitive process in which an organism has learnt to respond in a particular way to a stimulus. Thus it appears that they act impulsively.
Autoreceptors.
These are presynaptic receptors that provide feedback about activity in the synapse and therefore regulate the release of neurotransmitter.
Axon.
The part of a nerve cell that conducts electrical impulses away from the neuron’s cell body.
Basal ganglia.
A subcortical collection of cells comprising the striatum, the globus pallidus, and the substantia nigra.
Behavioral Approach System (BAS).
In Gray’s theory a system which is activated when the environment is indicating reward or punishment.
Behavioral genetics.
A scientific discipline which examines the role of genetics in behavior. It often uses twin studies or adoption studies to evaluate genetic and environmental influences on behavior.
Behavioral inhibition (BI).
The ability to stop a response. Considered by many to be the central deficit in ADHD.
Behavioral Inhibition System (BIS).
In Gray’s theory a system which detects mismatches between the environment and the person’s expectations by stopping ongoing behavior and directing cognitive resources to the mismatch.
Benzedrine.
Brand name for amphetamine.
BI.
See behavioral inhibition.
Catapres.
Brand name for Clonidine.
Catechol-O-methyl-transferase.
An enzyme that degrades dopamine, adrenaline, and noradrenaline and turns them into metabolites, thereby reducing their activity.
Cell body (or soma).
The area of a cell/neuron that contains the nucleus and therefore the genetic code for the cell.
Central executive.
In working memory the central executive is a theoretical cognitive system that controls and manages other subordinate cognitive processes.
Cerebral commisures.
The connections between the two cerebral hemispheres.
Chromosomes.
In genetics these are the organized structures comprising DNA wrapped around proteins to form an X-shape.
Cingulate cortex.
Part of the frontal lobes.
Clinical trials.
Studies in humans that are conducted to evaluate the safety and efficacy of new drugs or medical devices.
Clonidine.
(Brand name Catapres.) An agonist at the noradrenergic Alpha2 receptor.
Cocaine.
A highly addictive psychoactive drug with a similar pharmacology to methylphenidate. It increases dopamine in the synapse by blocking the dopamine transporter.
Cognitive behavioral therapy (CBT).
A psychotherapeutic method that helps the individual to change how they think (cognitive) and what they do (behavior).
Comorbidity.
The presence of one or more disorders (or diseases) in addition to the primary disease or disorder, e.g. ADHD and anxiety.
Concerta.
Brand name of methylphenidate. Slow-release formulation.
Conduct Disorder (CD).
A frequently comorbid diagnosis with ADHD.
Confidence intervals.
In statistics, confidence intervals aid interpretation of clinical-trial data by putting upper and lower limits on the likely size of any true effect. They provide more information that a straightforward p value as they give an idea of effect size.
Construct validity.
In animal models this refers to whether a model of behavior measures or correlates with the theorized psychological construct (e.g. behavioral inhibition/working memory) that it is said to measure.
Control group.
A comparison group in an experiment that is used to determine if the intervention alone has been effective and is not the result of other unspecified variables.
Corpus callosum.
The structure of the brain that connects and facilitates communication between the left and right cerebral hemispheres.
Cortex.
A sheet of neural tissue that is the outermost part of the brain. In evolutionary terms this is the most recent addition to the brain.
Cylert.
Brand name for pemoline.
DA.
See dopamine.
DAT.
See dopamine transporter.
DAT knockout mice.
Mice bred specifically not to have the dopamine transporter.
Delay discounting.
The extent to which consequences, or outcomes, decrease in effectiveness to control behavior as a function of there being a delay to their delivery. Higher rates of delay discounting are often operationalized as an index of impulsivity. In ADHD there is a tendency to work for small immediate rewards rather than larger rewards delivered later in time.
Dendrites.
The branched projections of a neuron that act to conduct the stimulation received from other cells to the cell body.
Deoxyribonucleic acid.
See DNA.
Dependence.
In addiction this is the state of needing a drug to operate within normal limits.
Depolarization.
The change in a cell’s membrane potential, making it more positive leading to an action potential.
Dexmethylphenidate.
(Brand name Focalin.) The D-isomer of methylphenidate.
Diagnosis.
In medicine, diagnosis is a label given for a medical condition or disease identified by its signs and symptoms.
Diagnostic criteria.
A set of requirements that need to be met prior to receiving a diagnosis.
Differential diagnosis.
A form of diagnosis which involves a process of elimination.
Dizygotic twins (DZ).
Sometimes called fraternal twins or non-identical twins, they occur when two eggs are fertilized by two sperm cells and are implanted in the uterus at the same time.
DNA (deoxyribonucleic acid).
A nucleic acid that contains the genetic instructions used in the development and functioning of all living organisms.
Dominant trait.
From Mendelian genetics. A characteristic that is observed whenever present in the genotype.
DOPA (dihydroxyphenylalanine).
A precursor to dopamine in its synthesis.
DOPAC (3, 4-dihydroxyphenylacetic acid).
A metabolite of dopamine.
Dopamine (DA).
A neurotransmitter in the brain.
Dopamine beta hydroxylase.
An enzyme involved in the synthesis of noradrenaline from dopamine.
Dopamine decarboxylase.
An enzyme involved in the synthesis of dopamine.
Dopamine transporter (DAT).
A membrane-spanning protein that provides the main mechanism through which dopamine is removed from the synapse.
Double-blind.
A study/experiment in which neither the participants nor the researchers know who belongs to the control group and the experimental group, thereby reducing bias.
Double helix.
The entwined structure of DNA strands.
DRD1; DRD2; DRD3; DRD4; DRD5, etc. gene.
Dopamine receptor genes.
DRD4/7R gene.
The dopamine receptor most frequently implicated in ADHD.
DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th edn).
The current diagnostic manual from the American Psychiatric Association.
Eclampsia.
A complication during pregnancy with seizures.
Ecological validity.
A study possessing ecological validity is close to the real-life situation.
EEG (electroencephalogram).
A machine which records the brain’s spontaneous electrical activity via multiple scalp-placed electrodes.
EF (executive function).
See executive functioning.
Encephalitis lethargica.
Also called sleeping sickness. This is an inflammation of the brain that can lead to an inability to speak or move. Upon reduction of the inflammation, children were seen to display the symptoms of ADHD.
Endophenotype.
The concept of an endophenotype in psychiatry is to fill the gap between the gene and the disease. In ADHD, behavioral inhibition can be considered an endophenotype because it is associated with various genes and is argued to be the central processing deficit in ADHD.
Epidemiology.
The branch of medicine that studies the causes, distribution, and control of disease/disorder in populations.
Epigenetics.
Refers to changes in phenotype (appearance) or gene expression caused by mechanisms other than changes in the underlying DNA sequence.
Epilepsy.
A common neurological disorder characterized by recurrent unprovoked seizures.
Episodic buffer.
In working memory a temporary storage system that can integrate information from different sources.
Equal Environment Assumption (EEA).
The assumption in twin studies that the environment remains equal for both twins.
Equasym.
A brand name of methylphenidate.
ERPs (event-related potentials).
Electrical activity as measured by EEG that is caused by processes such as memory and attention.
Error detection.
The ability to identify and rectify an error made.
Etiology.
The cause of a disorder.
Event-related potentials (ERPs).
See ERPs.
Evolutionary psychology.
A branch of psychology that attempts to explain psychological phenomena as adaptations derived from natural selection.
Executive functioning.
A theoretical construct thought to control and manage other cognitive processes, e.g. behavioral inhibition or working memory.
Face validity.
In animal models the similarities seen between the clinical symptoms of ADHD and the animal model’s behavioral repertoire.
Familial.
In genetics related to a family. A characteristic that runs in families.
Fatty Acid Deficiency Syndrome (FADS).
A syndrome of dry hair and skin, frequent thirst, and urination as a result of too little fatty acids.
Fatty acids.
Acids produced when fats are broken down and are found in oils and other fats of different foods. They are an important part of a healthy diet.
fMRI (functional magnetic resonance imaging).
An imaging technique to visualize the brain’s activity using electromagnets. It provides a high-resolution and detailed picture.
Focalin.
Brand name for dexmethylphenidate.
Fetal Alcohol Syndrome.
A disorder that can occur to the embryo when a pregnant woman drinks alcohol during pregnancy which causes brain damage.
Fornix.
A group of nerve fibers that extends from the hippocampus to the mamillary body of the hypothalamus.
Fragile X.
A genetic syndrome which results in a spectrum of characteristic physical, intellectual, emotional, and behavioral features which range from severe to mild.
Frontal lobes.
An area of the cortex located at the front of each cerebral hemisphere. This is the area in which executive functions are located.
Gene.
The basic unit of heredity in a living organism which holds the information to build and maintain an organism’s cells and pass genetic traits to offspring.
Genotype.
The genetic constitution of a cell.
Glial cells.
Cells that provide support and protection for the brain’s neurons.
Globus pallidus.
A subcortical structure that is part of the basal ganglia.
Glutamate.
An excitatory amino acid that is a neurotransmitter.
Go/no-go task.
A task of behavioral inhibition in which one has to stop a response when a particular stimulus is presented.
Gray matter.
The tissue in the brain that contains neural cell bodies, in contrast to white matter, which does not. The color comes from blood vessels and neuronal cell bodies.
Guanfacine.
(Brand name Tenex.) An agonist at the noradrenergic Alpha2 receptor.
Heritability estimates.
A statistic about the variance of a characteristic in a population that can be accounted for by genetics. Most frequently estimated by comparing resemblances between twins.
Heteroreceptors.
A receptor regulating the synthesis and/or the release of a different neurotransmitter.
Hippocampus.
Part of the limbic system and involved in memory.
Human genome.
The entirety of an organism’s hereditary information.
HVA (homovanillic acid).
A dopamine metabolite.
Hyperactivity.
The physical state in which a person is abnormally active. One of the three main symptoms of ADHD.
Hyperkinetic Disorder (HKD).
The ICD-10 name for ADHD. Best describes the combined type as defined by the DSM-IV.
Hypoxia.
The deprivation of oxygen to the organs of the body.
Iatrogenic.
The inadvertent adverse effects caused by or resulting from medical treatment.
ICD-10.
The International Statistical Classification of Diseases and Related Health Problems classification system of the World Health Organization (WHO).
Impulsivity.
The inclination of an individual to initiate behavior without adequate forethought as to the consequences of their actions, acting on the spur of the moment. One of the three main symptoms of ADHD.
In utero.
In the uterus.
Inattention.
Lack of attention. One of the three key symptoms of ADHD.
Inhibitory control.
The ability to stop oneself doing something. See behavioral inhibition.
Ionotropic receptor.
An ion-gated receptor that requires a molecule to react with the receptor to allow the flow of ions from the outside of a cell to the inside of the cell.
Kinesthetic.
The sensation of movement or strain in muscles, tendons, and joints.
Lesion.
The abnormal tissue found on or in an organism – normally causing destruction.
Ligand.
A chemical that binds to a receptor.
Limbic system.
A network of cells that are thought to be involved in emotions and learning.
Linkage.
In genetics, linkage refers to the fact that certain genes tend to be inherited together, because they are on the same chromosome.
Lisdexamfetamine.
(Brand name Vyvanse.) A prodrug to dextroamphetamine.
Mamillary bodies.
Part of the limbic system thought to be involved in memory.
Mendelian genetics.
The type of genetic transmission described by Mendel in which characteristics or traits are passed on from generation to generation. See dominant trait and recessive trait.
Mesocortical pathway.
A dopamine pathway in the brain connecting the VTA (subcortical) to the cortex.
Mesolimbic pathway.
A dopamine pathway connecting the VTA (subcortical) to the limbic system. The main connection is with the nucleus accumbens.
Meta-analysis.
In statistics, an analysis that combines the results of several studies that address a set of related research hypotheses, e.g. all the studies on methylphenidate and impulsivity.
Metabotropic receptor.
A type of receptor that involves an intermediate biochemical process before activation.
Methylphenidate.
A psychostimulant and the main treatment for ADHD. Its pharmacological mechanism is to block the dopamine transporter and thereby increase dopamine levels in the synapse.
MHPG.
A metabolite of noradrenaline.
Minimal Brain Dysfunction.
An early term used prior to ADHD which described the syndrome of behaviors characteristic of ADHD.
Misuse.
Any non-medical consumption of a drug.
Modafinil.
A broad-spectrum psychostimulant that is used off-label in ADHD treatment.
Monozygotic twins (MZ).
These are identical twins which occur when a single egg is fertilized to form one zygote (monozygotic) and then divides into two separate embryos. These twins have identical genes.
Motivational inhibition.
The inhibition responsive to emotionally salient stimuli, e.g. reward and punishment, unexpected mismatches, and social unfamiliarity.
MRS (Magnetic Resonance Spectroscopy).
A technique used to visualize the brain.
MTA study.
The Multimodal Treatment Study of Children with ADHD conducted in the USA. Compared methylphenidate with behavioral therapy and a combination of the two.
Myelin.
A glial outgrowth that insulates neurons and speeds up neural communication.
NAcc (nucleus accumbens).
Part of the mesolimbic system.
Narcolepsy.
A condition that is characterized by excessive daytime sleepiness in which a person experiences extreme fatigue and possibly falls asleep at inappropriate times.
Neurofibromatosis.
A genetic disorder in which the nerve tissue grows tumors that may cause serious damage to the nerves.
Neuroimaging.
The use of various techniques to visualize the anatomy and function of the living brain.
Neuropsychological tests.
Tests that are specifically designed to measure a psychological function known to be linked to a particular brain structure or pathway.
Neurotransmitter.
An endogenous chemical which relays, amplifies, and modulates signals between neurons.
Nicotine.
The psychoactive chemical in tobacco. Acts at the cholinergic nicotine receptor.
Nigrostriatal pathway.
A dopamine containing set of neurons that extend from the substantia nigra to the striatum.
Noradrenaline.
A neurotransmitter.
Norepinephrine.
See noradrenaline (US version).
Normative data.
The normal or average scores for any given test.
Nucleic acids.
Molecules that carry genetic information. See DNA.
Nucleus accumbens.
A collection of neurons thought to play an important role in reward, pleasure, and addiction.
Occipital lobe.
Rear part of the cortex involved in visual perception.
Oppositional Defiant Disorder (ODD).
A DSM diagnosis that describes disobedient, hostile, and defiant behavior towards authority figures which goes beyond the bounds of normal childhood behavior. Often seen with ADHD.
Orbitofrontal cortex.
Part of the frontal lobes and involved in cognition and executive functions.
Orienting.
A response in which attention is directed to a change in the environment.
p value.
In statistics, the value in which a hypothesis is accepted or rejected. Provides an estimate of the chance or the probability that the effect seen is due or not due to the intervention or treatment. Less than 5 percent (or p < .05) is considered significant.
Parietal lobes.
Cortical regions of the brain that are situated behind the frontal lobes and are involved in integrating sensory inputs, e.g. hearing and seeing.
Pathological.
Diseased or abnormal.
Pemoline.
(Brand name Cylert.) Once-used psychostimulant in the treatment of ADHD. Increases dopamine release and blocks its reuptake.
Penetrance.
In genetics, it is the proportion of individuals carrying a particular variation of a gene that also express an associated trait (phenotype), e.g. a dopamine gene and impulsivity.
PET scan.
A technique used to visualize the brain using radioactive tracers.
Pharmacodynamics.
The physiological effects of drugs on the body.
Pharmacokinetics.
The movement and fate of drugs. Includes the route of administration, e.g. oral or injection and how it is metabolized.
Pharmakon.
The active ingredient in a drug. Latin for drug.
Phase I, II, III, and IV clinical trails.
The different levels of assessing the value and suitability of a drug or medical device.
Phenocopy.
In genetics, when an individual whose phenotype under a particular environmental condition is identical to that one of another individual whose phenotype is determined by the genotype.
Phenotype.
Any observable characteristic or trait of an organism. Phenotypes result from the expression of an organism’s genes as well as the influence of environmental factors and possible interactions between the two.
Phonological loop.
Part of the working memory concept and deals with auditory information.
Placebo.
An inactive medical intervention, e.g. a sugar pill. No ingredients are thought to have an effect.
Placebo-controlled study.
A study in which an active drug is compared with a placebo.
Plumbism.
Lead poisoning.
Polymorphisms.
In genetics, having multiple alleles of a gene (e.g. the different variants of the DRD4 gene) within a population that can express different phenotypes.
Postsynaptic neuron.
Neuron that is on the other side of the synapse to the neuron that is sending a message.
Predictive validity.
In psychometrics, the extent to which a score on a scale or test predicts scores on some criterion measure, e.g. scores on an IQ test measure intelligence. In animal models, the extent to which one can predict outcomes of interventions or treatments on the basis of the human equivalent.
Prefrontal cortex.
Part of the frontal lobe.
Prepotent response.
A well-learnt response.
Presynaptic neuron.
The neuron that sends a message across a synapse.
Prevalence.
In epidemiology, an estimate of how common a condition is within a population over a certain period of time.
Probability.
A measure of how likely it is that some event will occur. See p value.
Prodrug.
A pharmacological substance (drug) that is administered in an inactive (or significantly less active) form; once administered, the prodrug is metabolized into an active metabolite, thereby providing effective treatment.
Prognosis.
Medical term to describe the likely outcome of an illness.
Psychobiologist.
Me. A person who studies the biological basis of behavior.
Psychoeducation.
Refers to the education offered to people who live with a psychological disturbance.
Psychometric tests.
Questionnaires or tests to measure psychological concepts such as IQ.
Psychopharmacology.
The study of the action of drugs on behavior.
Psychometrics.
The field of study concerned with the theory and technique of psychological measurement, which includes the measurement of knowledge, abilities, attitudes, and personality traits.
Psychophysiology.
Studies the physiological bases of psychological processes and uses EEG etc.
Psychosocial.
The interaction between psychological constructs and the social environment.
Psychostimulant.
A drug that activates neural systems and brings about a psychological change.
Randomized.
In experimental design, the allocation of participants is not guided in a particular direction.
Randomized controlled trial.
A clinical trial that randomly allocates participants to control and/or treatment groups.
Rate-dependent hypothesis.
When the effects of a drug differ depending on the activity pre-existing levels of the organism: e.g. when activity level is high amphetamine reduces it, when activity is low, amphetamine increases it.
Receptors.
Proteins that permit neurotransmitters (and drugs) to attach themselves and conduct signals.
Recessive trait.
From Mendelian genetics. A characteristic that is not observed when paired with a dominant trait in the genotype.
Reductionism.
An approach to understand the nature of complex things by reducing them to the interactions of their parts, or to simpler or more fundamental things.
Reflex.
An involuntary and near instantaneous movement in response to a stimulus.
Regression-to-the-mean.
In statistics, the phenomenon that a variable that is extreme on its first measurement will tend to be closer to the average on a later measurement.
Reinforcement.
A process in which a response is strengthened by the fear of punishment or the anticipation of reward.
Reliability.
The consistency of a set of measurements or measuring instrument.
Research methodology.
The use of scientific methods and principles in research, e.g. double-blind.
Response inhibition.
See behavioral inhibition.
Resting potential.
The electrical potential across a nerve cell membrane before it is stimulated and an action potential occurs.
Reward.
In psychology, something that, when offered, causes a behavior to increase, e.g. money increases work rate.
Reward prediction error.
The phasic dopamine response that occurs if a reward is unpredicted, not available, or delayed.
Ritalin.
Brand name for methylphenidate.
Saccadic eye movements.
Very fast movement of an eye.
Self-administration.
In animal models, the voluntary infusion of a drug, e.g. cocaine by pressing a lever in a special cage. A measure of addiction.
Sensitization.
The progressive amplification of a response following repeated administrations of a drug or other stimulus. Sensitization of dopamine neurons has been argued to be the common mechanism underlying addiction.
Serotonin (5-HT).
An indolamine neurotransmitter.
Sex chromosome abnormalities.
Aberrations that are restricted to the sex chromosomes and are rarely fatal, e.g. Turner syndrome.
SHR.
See spontaneous hypertensive rat.
Significance.
In statistics a result is called significant if it is unlikely to have occurred by chance.
Single-blind experiment.
An experiment in which the individual participants do not know what group they are in (control or experimental), but the experimenter is aware of the group that the participant is in. Allows bias from the experimenter to be present, therefore double-blind studies are preferable.
Single photon emission computed tomography (SPECT).
A technique used to visualize the brain. Uses radiation.
Sleep apnea.
A sleep disorder characterized by pauses in breathing during sleep.
Spontaneous hypertensive rat (SHR).
An animal model of ADHD.
Stereoisomers.
Isomers (compounds with the same molecular formula) which have their atoms connected in the same sequence but differ in the way the atoms are oriented in space. Here we have D- and L- isomers as in D-amphetamine.
Stimulus–response.
In classical conditioning where a stimulus (e.g. food) produces a response (e.g. salivation).
Stop-Signal Reaction Time task.
A laboratory measure of behavioral inhibition in which an ongoing response is to be terminated upon the appearance of a Stop signal.
Strattera.
Brand name of atomoxetine.
Striatum.
A subcortical region of the basal ganglia involved in ADHD pathology and treatment.
Subcortical.
Regions of the brain that are older and beneath the cortex.
Substance Use Disorder (SUD).
From the DSM-IV and involves the dependence on, or abuse of, alcohol and/or drugs.
Substantia nigra.
Part of the basal ganglia and plays a role in reward, addiction, and movement.
SUD.
See Substance Use Disorder.
Supervisory Attentional System (SAS).
A theoretical construct similar to working memory that offers an explanation of executive functioning and the frontal lobes.
Sustained attention.
The ability to maintain a consistent behavioral response during continuous and repetitive activity.
Synapse.
The space between two neurons in which communication occurs.
Tenex.
Brand name for guanfacine.
Teratogen.
A substance or environmental agent which causes the development of abnormal cells during fetal growth and results in physical defects in the fetus. The most notable one in history is thalidomide.
Theory of Mind (ToM).
The ability to attribute mental states – e.g. beliefs, intents, desires, thoughts, etc. – to oneself and others and to understand that others have beliefs, desires, and intentions that are different from one’s own.
Thyroid disorder.
A medical condition impairing the function of the thyroid.
Titration.
The process of gradually adjusting the dose of a medication until the desired effect is achieved.
Tourette’s syndrome.
An inherited psychiatric disorder with onset in childhood, characterized by the presence of multiple physical (motor) tics and at least one vocal tic.
Twin studies.
A type of study design in behavior genetics which looks at the role of environmental and genetic causes in behavior.
Tyrosine hydroxylase.
The enzyme responsible for the conversion of the amino acid L-tyrosine to DOPA, which is the precursor for dopamine, which in turn is a precursor for noradrenaline and adrenaline.
Validity.
In psychology refers to the degree to which evidence and theory support the interpretations of test scores.
Ventouse.
A vacuum device used to assist the delivery of a baby.
Ventral tegmental area (VTA).
A subcortical region of the brain that is widely implicated in reward circuitry, cognition, motivation, drug addiction, and several psychiatric disorders, including ADHD.
Vesicle.
A structure in the presynaptic neuron that stores various neurotransmitters that are to be released into the synapse.
Visuospatial Sketchpad.
A part of working memory which holds information about what we see.
VMA (vanillylmandelic acid).
A metabolite of adrenaline and noradrenaline.
VTA.
See ventral tegmental area.
Vyvanse.
Brand name for lisdexamfetamine.
White matter.
Tissue in the brain that consists mostly of myelinated axons, which appear white because myelin is composed of lipid tissue.
Working memory.
A theoretical construct in psychology which describes executive functions and attentional aspects of memory and is involved in the integration, processing, disposal, and retrieval of information.