AP Psych 1.3 Definitions

Neuron

The basic unit of the nervous system, a cell that transmits nerve impulses.

Glia

Supportive cells in the nervous system that assist and protect neurons.

Threshold

The level of stimulation required to trigger a neural impulse.

Synapse

The junction between two neurons where communication occurs via neurotransmitters.

Neurotransmitters

Chemical messengers that transmit signals across a synapse from one neuron to another.

Endorphins

Natural chemicals in the body that help relieve pain and induce feelings of pleasure.

Psychoactive Drug

A substance that alters brain function and results in changes in perception, mood, consciousness, or behavior.

Substance Use Disorder

A condition characterized by an individual’s inability to stop using a substance despite negative consequences.

Depressants

Substances that reduce activity in the CNS, often leading to relaxation and sedation.

Stimulants

Substances that increase activity in the CNS, leading to alertness and energy.

Tolerance

A state in which a person requires increasing amounts of a substance to achieve the same effect.

Addiction

A compulsive need for and use of a substance despite harmful consequences.

Withdrawal

Symptoms that occur when a person reduces or stops intake of a substance they have become dependent on.

Opioids

A class of drugs derived from the opium poppy, used for pain relief but with a high potential for addiction.