Neuroscience: Central, Peripheral, and Brain Structures Overview

Central nervous system

The part of the nervous system that includes the brain and spinal cord.

Peripheral nervous system

The part of the nervous system that includes all the nerves outside the central nervous system.

Sensory (afferent) division

The division of the peripheral nervous system that transmits sensory information to the central nervous system.

Motor (efferent) division

The division of the peripheral nervous system that transmits motor commands from the central nervous system to the muscles.

Somatic

The part of the motor division that controls voluntary movements.

Autonomic

The part of the motor division that controls involuntary functions.

Sympathetic

The division of the autonomic nervous system that prepares the body for 'fight or flight' responses.

Parasympathetic

The division of the autonomic nervous system that promotes 'rest and digest' functions.

Ependymal

Cells that line the ventricles of the brain and produce cerebrospinal fluid.

Oligodendrocytes

Cells that form the myelin sheath around neurons in the central nervous system.

Schwann cells

Cells that form the myelin sheath around neurons in the peripheral nervous system.

Astrocytes

Star-shaped glial cells that support neurons and maintain the blood-brain barrier.

Satellite cells

Cells that provide support and nutrients to neurons in the peripheral nervous system.

Microglia

Immune cells of the central nervous system that respond to injury or disease.

Dendrites

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

Soma / cell body

The part of a neuron that contains the nucleus and organelles.

Axons

Long projections of a neuron that transmit electrical impulses away from the cell body.

Axon terminal

The end of an axon where neurotransmitters are released to communicate with other neurons.

Synapse

The junction between two neurons where communication occurs.

Sensory neurons

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

Motor neurons

Neurons that carry motor commands from the central nervous system to the muscles.

Interneurons

Neurons that connect sensory and motor neurons within the central nervous system.

General reflex arc

The neural pathway that mediates a reflex action.

Stretch reflex arc

A reflex that causes a muscle to contract in response to its being stretched.

Withdrawal reflex arc

A reflex that causes the body to withdraw from a painful stimulus.

Threshold

The membrane potential that must be reached for an action potential to occur.

Depolarization

The phase of an action potential where the membrane potential becomes more positive.

Repolarization

The phase of an action potential where the membrane potential returns to a negative value.

Hyperpolarization

The phase of an action potential where the membrane potential becomes more negative than the resting potential.

Sodium-potassium pump

A membrane protein that pumps sodium out of the cell and potassium into the cell to maintain resting membrane potential.

Cerebrospinal fluid

Fluid that surrounds and protects the brain and spinal cord.

Brainstem

The part of the brain that connects the brain to the spinal cord and controls basic life functions.

Reticular formation

A network of neurons in the brainstem that plays a role in arousal and consciousness.

Lateral ventricle

A cavity in the brain that contains cerebrospinal fluid.

Third ventricle

A narrow cavity in the brain that contains cerebrospinal fluid.

Pineal gland

A small endocrine gland in the brain that produces melatonin.

Pituitary gland

An endocrine gland that regulates various hormonal functions in the body.

Cerebrum / cerebral hemispheres

The largest part of the brain responsible for higher brain functions.

Longitudinal fissure

The deep groove that divides the brain into left and right hemispheres.

Frontal lobe

The part of the brain responsible for executive functions, decision making, and motor control.

Parietal lobe

The part of the brain responsible for processing sensory information.

Occipital lobe

The part of the brain responsible for visual processing.

Temporal lobe

The part of the brain responsible for processing auditory information and memory.

Thalamus

A relay station for sensory information to the cerebral cortex.

Cerebellum

The part of the brain that coordinates voluntary movements and balance.

Medulla oblongata

The part of the brainstem that controls vital autonomic functions.

Pons

The part of the brainstem that connects different parts of the brain and regulates sleep.

Midbrain

The part of the brainstem that plays a role in vision, hearing, and motor control.