AP PSYCH UNIT ONE

Neuron

A nerve cell that transmits electrical and chemical signals throughout the nervous system.

Glial Cells

Supportive cells in the nervous system that provide structural, nutritional, and metabolic support to neurons.

Dendrites

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

Cell Body (Soma)

The central part of a neuron containing the nucleus and essential organelles.

Axon

A long, slender projection of a neuron that conducts electrical impulses away from the cell body.

Myelin Sheath

A fatty layer encasing the axon of many neurons, which speeds up neural transmission.

Terminal Buttons

The small swellings at the end of an axon that release neurotransmitters into the synapse.

Neurotransmitters

Chemical messengers released by neurons that transmit signals across a synapse to another neuron or cell.

Synapse

The junction between two neurons where neurotransmitters are released and received.

Receptor Sites

Specialized areas on the surface of a neuron or other cell where neurotransmitters bind and elicit a response.

Threshold

The minimum level of stimulation required to trigger an action potential in a neuron.

Action Potential

A rapid, all-or-nothing electrical signal that travels along the axon of a neuron.

All-or-None Principle

The principle stating that a neuron either fires an action potential at full strength or does not fire at all.

Neural Firing

The process by which a neuron generates and transmits an action potential.

Excitatory Neurotransmitters

Chemicals that increase the likelihood of a neuron firing an action potential.

Inhibitory Neurotransmitters

Chemicals that decrease the likelihood of a neuron firing an action potential.

Acetylcholine

A neurotransmitter involved in muscle contraction and cognitive functions like memory.

Dopamine

A neurotransmitter associated with pleasure, reward, and motor control.

Endorphins

Neurotransmitters that act as natural painkillers and mood enhancers.

Serotonin

A neurotransmitter that regulates mood, sleep, and appetite.

Afferent Neurons

Neurons that carry sensory information from the body to the central nervous system.

Efferent Neurons

Neurons that transmit motor commands from the central nervous system to muscles and glands.

Central Nervous System (CNS)

The brain and spinal cord, responsible for processing and sending information throughout the body.

Spinal Cord

The long, thin, tubular structure extending from the brainstem that transmits neural signals between the brain and the rest of the body.

Peripheral Nervous System (PNS)

The network of nerves outside the central nervous system that connects the CNS to limbs and organs.

Somatic Nervous System

The part of the peripheral nervous system that controls voluntary movements and sensory information.

Autonomic Nervous System

The part of the peripheral nervous system that regulates involuntary bodily functions like heartbeat and digestion.

Sympathetic Nervous System

The division of the autonomic nervous system responsible for the "fight or flight" response.

Parasympathetic Nervous System

The division of the autonomic nervous system responsible for "rest and digest" functions.

Psychoactive Drugs

Substances that alter mood, perception, or consciousness by affecting the nervous system.

Agonists

Drugs or substances that enhance the activity of neurotransmitters.

Antagonists

Drugs or substances that block or inhibit the activity of neurotransmitters.

Tolerance

The reduced effectiveness of a drug due to repeated use, requiring larger doses to achieve the same effect.

Dependence and Withdrawal

The physical and psychological symptoms that occur when a person stops using a drug on which they are dependent.

Stimulants

Drugs that increase activity in the central nervous system, leading to heightened alertness and energy.

Depressants

Drugs that decrease activity in the central nervous system, resulting in relaxation and drowsiness.

Hallucinogens

Drugs that alter perception, mood, and cognitive processes, often causing hallucinations.

Opiates

Drugs derived from the opium poppy that relieve pain and induce euphoria, such as morphine and heroin.

Hindbrain

The part of the brain including the medulla, pons, and cerebellum, responsible for basic life functions and motor control.

Medulla

The brainstem structure that controls vital functions like heartbeat and breathing.

Pons

The brainstem structure involved in regulating sleep, respiration, and facial movements.

Cerebellum

The brain structure responsible for coordination, balance, and fine motor control.

Midbrain

The central part of the brain involved in