Mental Health Disorders & Addiction Vocabulary

Acetylcholine

A neurotransmitter involved in neuromuscular transmission, parasympathetic control, and central modulation.

Addiction

A chronic, relapsing disorder characterized by compulsive drug seeking and use despite harmful consequences.

Adenosine

A neuromodulator that promotes sleep and suppresses arousal.

Agonist

A substance that activates a receptor to produce a biological response.

Alcohol Dependence

A condition involving tolerance, withdrawal symptoms, and compulsive use of alcohol.

Antagonist

A substance that blocks or dampens a biological response by binding to a receptor.

Anhedonia

Loss of interest or pleasure in activities once found enjoyable, commonly seen in depression.

Anxiety Disorder

A mental health disorder characterized by chronic worry, restlessness, and physical symptoms like muscle tension and fatigue.

Blood-Brain Barrier

A selective barrier that protects the brain from potentially harmful substances in the bloodstream.

CNS Depressants

Drugs like alcohol, benzodiazepines that slow down brain activity; withdrawal may lead to seizures or agitation.

Cognition

Mental processes like thinking, learning, memory, and attention.

Conditioning

A learning process in which a behavior becomes more likely due to association with a stimulus.

Cortisol

A stress hormone that may be elevated in mood disorders and linked to inflammation.

Dependence

A state where neurons adapt to drug presence and function abnormally without it.

Dopamine

A neurotransmitter involved in reward, motivation, and motor function.

Dysphoric Mood

A general feeling of unease or dissatisfaction, common in mood disorders.

Endorphins

Natural opioid-like neurotransmitters that reduce pain and create a sense of well-being.

Excitatory Neurotransmitter

A neurotransmitter that increases the likelihood of a neuron firing.

GABA (Gamma-Aminobutyric Acid)

The main inhibitory neurotransmitter in the brain, calming neural activity.

Glutamate

The primary excitatory neurotransmitter involved in learning and memory.

Histamine

A neurotransmitter that promotes wakefulness and alertness.

HPA Axis

Hypothalamic-pituitary-adrenal axis; plays a key role in the stress response.

Lethal Dose (LD50)

The amount of a substance required to kill 50% of a test population.

Mesolimbic Pathway

A dopaminergic pathway in the brain associated with reward and pleasure.

Mesocortical Pathway

Dopaminergic pathway involved in cognition, emotion, and executive function.

Mood Disorder

A category of mental health disorders that includes major depressive disorder and bipolar disorder.

Neurotransmitter

Chemicals that transmit signals across synapses between neurons.

Nigrostriatal Pathway

Dopamine pathway that regulates movement; degeneration is linked to Parkinson’s disease.

Norepinephrine

A neurotransmitter involved in arousal, stress, and sympathetic nervous system responses.

Opioids

Substances that bind to opioid receptors, often used for pain relief; highly addictive.

Pathway (Neural)

A series of connected neurons that control a specific function.

Potency

A measure of drug strength or effectiveness.

Prediction Error

The difference between expected and actual outcomes, used by the brain to learn and adjust behavior.

Psychostimulants

Drugs that increase activity in the brain.

Reuptake Inhibitor

A substance that blocks the reabsorption of neurotransmitters, increasing their availability.

Reward Prediction Error (RPE)

A process where unexpected rewards cause a dopamine spike, reinforcing future behaviors.

Route of Administration

How a drug is taken (e.g., oral, IV, inhaled, sublingual).

Serotonin

A neurotransmitter associated with mood, sleep, and appetite regulation.

Stimulants

Drugs that increase neural activity and energy.

Tolerance

The need to take more of a substance to achieve the same effect.

Tuberoinfundibular Pathway

A dopamine pathway that regulates prolactin secretion.

Withdrawal

A set of symptoms that occur when stopping or reducing intake of an addictive substance.