drug & beh txt 4-6

Alcohol

A substance that inhibits antidiuretic hormone (ADH), disrupting fluid balance.

Homeostasis

The body's maintenance of stable internal conditions.

Vasopressin

A hormone released during alcohol withdrawal that leads to water retention.

Glial Cells

Non-neuronal cells in the nervous system that provide support, nourishment, and protection to neurons.

Action Potential

An electrical signal that allows neurons to communicate, generated by opening ion channels.

Depolarization

A change in a neuron's membrane potential making it more positive, increasing action potential likelihood.

Sympathetic Nervous System

Part of the autonomic nervous system responsible for 'fight or flight' responses; uses norepinephrine.

Parasympathetic Nervous System

Part of the autonomic nervous system responsible for 'rest and digest'; uses acetylcholine.

Basal Ganglia

A group of brain structures involved in motor control and muscle tone maintenance.

Dopamine Loss Effects

Leads to movement disorders like rigidity and difficulty initiating movement, as seen in Parkinson's disease.

Mesolimbic Pathway

A dopamine pathway activated by natural rewards and drugs, reinforcing drug-seeking behavior.

Neurotransmission

The process by which neurotransmitters communicate between neurons.

PET (Positron Emission Tomography)

A brain imaging technique that uses radioactive chemicals to visualize metabolic processes.

fMRI (Functional Magnetic Resonance Imaging)

A brain imaging technique that measures metabolic activity based on blood flow changes.

Drug Names

The three types are chemical name, generic name, and brand name.

Therapeutic Index (TI)

The ratio of toxic dose (TD50) to effective dose (ED50) of a drug, indicating safety margin.

Agonist

A drug that binds to a receptor and activates it, mimicking neurotransmitter effects.

Antagonist

A drug that binds to a receptor but blocks it, preventing neurotransmitter effects.

CYP450 Enzymes

Liver enzymes responsible for metabolizing many drugs.

Dendrites

Branch-like extensions of a neuron that receive signals from other neurons.

Endorphins

Endogenous substances involved in pain relief and reward, similar to morphine.

GABA (γ-aminobutyric acid)

A major inhibitory neurotransmitter in the central nervous system.

Glutamate

A major excitatory neurotransmitter in the central nervous system.

Half-Life

The time it takes for a drug's concentration in the blood to reduce by half.

Hallucinogen

A drug that alters perception, thought, and mood.

Metabolism

The process by which the body breaks down drugs.

Reuptake

The process by which neurotransmitters are taken back into the presynaptic neuron.

Repolarization

The return of a neuron's membrane potential to its resting state after depolarization.

Norepinephrine

A neurotransmitter involved in arousal and regulation of various bodily functions.

Tolerance

Decreased response to a drug after repeated use, requiring higher doses for the same effect.

Withdrawal

A set of symptoms occurring after discontinuation of a drug used for a prolonged period.

Placebo Effect

A physiological effect produced by an inactive substance that the recipient believes is real.

Potency

The amount of a drug required to produce a specific effect.

Psychoactive Drug

A drug that alters mood, thought processes, or behavior.

Dopamine

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

Nucleus Accumbens

A brain region associated with the mesolimbic pathway and reward processing.

Astrocytes

A type of glial cell that supports neurons and regulates their activity.

Blood-Brain Barrier

A protective barrier that prevents many substances from entering the brain.

Somatic Nervous System

Part of the peripheral nervous system controlling voluntary muscle movements.

Nigrostriatal Pathway

A dopamine pathway important for motor control.

Cerebral Cortex

The outer layer of the brain responsible for high-level cognitive functions.