Anatomy of the Mind: Physiological Psychology Review

Neuron

Specialized cell that transmits information through electrical and chemical signals.

Dendrites

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

Soma (Cell Body)

Part of the neuron that contains the nucleus and maintains the life of the cell.

Axon

Long, tube-like structure that carries the neural message away from the soma to the terminal buttons.

Myelin Sheath

Fatty substance that coats axons to insulate, protect, and speed up neural impulses.

Terminal Buttons

Endpoints of the axon that release neurotransmitters into the synapse.

Synapse

Microscopic gap between the sending neuron and the receiving neuron.

Action Potential

Rapid spike in positive charge within a neuron, resulting from the influx of sodium ions.

Resting Potential

State of the neuron when it is polarized and at rest, approximately -70mV.

All-or-None Principle

A neuron either fires at full strength or not at all, regardless of stimulus strength.

Neurotransmitter

Chemical messengers that cross the synapse to bind with receptor sites on the next neuron.

Acetylcholine (ACh)

Neurotransmitter involved in muscle action, learning, and memory.

Dopamine

Neurotransmitter that regulates movement, learning, attention, and emotion.

Serotonin

Neurotransmitter that affects mood, hunger, sleep, and arousal.

Norepinephrine

Neurotransmitter associated with alertness and arousal during stress.

GABA

Major inhibitory neurotransmitter that calms firing in the nervous system.

Glutamate

Major excitatory neurotransmitter that encourages firing in the nervous system.

Agonists

Substances that mimic neurotransmitters and enhance their effects.

Antagonists

Substances that block neurotransmitter functions.

Central Nervous System (CNS)

Composed of the brain and spinal cord; controlling center of the body.

Peripheral Nervous System (PNS)

Connects the CNS to the rest of the body and is divided into somatic and autonomic systems.

Sympathetic Nervous System

Part of the autonomic nervous system that mobilizes energy in stressful situations.

Parasympathetic Nervous System

Part of the autonomic nervous system that conserves energy and calms the body.

Brainstem

Responsible for automatic survival functions; includes the medulla and pons.

Limbic System

Associated with emotions and drives; includes the amygdala, hypothalamus, and hippocampus.

Cerebral Cortex

Outer layer of the brain responsible for complex thought, divided into four lobes.

Broca’s Area

Region in the left hemisphere responsible for language expression and production.

Wernicke’s Area

Region in the left hemisphere responsible for language reception and comprehension.