The Brain: Structure and Function

A comprehensive set of flashcards covering the structure and function of the brain, including key terms and definitions.

Neuron

The basic building block of the nervous system; a nerve cell that transmits electrical and chemical signals.

Dendrite

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

Soma (Cell Body)

Contains the nucleus and keeps the neuron alive and functioning.

Axon

A long, slender projection of a neuron that conducts electrical impulses away from the cell body to other neurons, muscles, or glands.

Myelin Sheath

A fatty tissue layer segmentally encasing the axons of some neurons, enabling greater transmission speed of neural impulses.

Nodes of Ranvier

Gaps in the myelin sheath along the axon, where the electrical signal is regenerated.

Axon Terminal (Terminal Buttons)

The endpoint of a neuron where neurotransmitters are stored and released.

Synapse (Synaptic Cleft)

The junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron.

Neurotransmitters

Chemical messengers that cross the synaptic gaps between neurons, binding to receptor sites on the receiving neuron.

Reuptake

The reabsorption of a neurotransmitter by the presynaptic neuron after it has performed its function.

Agonist

A molecule that binds to a receptor site and stimulates a response, mimicking the effect of a natural neurotransmitter.

Antagonist

A molecule that blocks a receptor site and inhibits or prevents a response, blocking the effect of a natural neurotransmitter.

Brainstem

The oldest part and central core of the brain, responsible for automatic survival functions.

Medulla

Located at the base of the brainstem; controls heartbeat and breathing.

Pons

Sits above the medulla; helps coordinate movements and sleep.

Thalamus

The brain's sensory control center, directing messages to the sensory receiving areas in the cortex.

Reticular Formation

A nerve network that travels through the brainstem and thalamus, controlling arousal and attention.

Cerebellum

'Little brain' at the rear of the brainstem; processes sensory input and coordinates movement.

Limbic System

Neural system located below the cerebral hemispheres, associated with emotions and drives.

Amygdala

Two lima-bean-sized neural clusters in the limbic system; linked to emotion, particularly fear and aggression.

Hypothalamus

A neural structure that directs several maintenance activities and governs the endocrine system via the pituitary gland.

Hippocampus

A neural center that helps process explicit memories for storage.

Cerebral Cortex

The intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body's ultimate control center.

Frontal Lobe

Involved in speaking, muscle movements, and making plans and judgments.

Parietal Lobe

Receives sensory input for touch and body position; spatial awareness.

Occipital Lobe

Includes areas that receive information from the visual fields.

Temporal Lobe

Includes the auditory areas, receiving information primarily from the opposite ear.

Motor Cortex

An area at the rear of the frontal lobes that controls voluntary movements.

Somatosensory Cortex

Area at the front of the parietal lobes that registers and processes body touch and movement sensations.

Broca's Area

Controls language expression; an area of the frontal lobe that directs muscle movements involved in speech.

Wernicke's Area

Controls language reception; a brain area involved in comprehension and expression.

Corpus Callosum

The large band of neural fibers connecting the two brain hemispheres and carrying messages between them.

Plasticity

The brain's ability to change by reorganizing after damage or building new pathways based on experience.

Neurogenesis

The formation of new neurons.