Nervous System Intro

central nervous system (CNS)

central nervous system (CNS)

brain and spinal cord

Peripheral Nervous System (PNS)

the sensory and motor neurons that connect the CNS to the rest of the body

afferent neurons

neurons that carry sensory information to the CNS

efferent neurons

neurons that take information from the central nervous system to the rest of the body

glial cells

cells in the nervous system that support, nourish, and protect neurons

Astrocytes (CNS)

connect neurons and capillaries and protect CNS

Microglia (CNS)

phagocytic cells that ingest and break down waste products and pathogens in the CNS

ependymal cells (CNS)

produce cerebrospinal fluid

Oligodendrocytes(CNS)

Form myelin sheath in CNS

Schwann cells (PNS)

Form myelin sheath in the peripheral nervous system

Dendrites

Branchlike parts of a neuron that are specialized to receive information.

Soma

cell body of a neuron

Nodes of Ranvier

gaps in myelin sheath along the axon

myelin sheath

insulates and helps speed neural impulses

axon terminals

Branches at the end of the axon

action potential

a neural impulse; a brief electrical charge that travels down an axon

potassium channels

Passive channel, opens at +40mV

sodium channels

Passive channel, opens at -55mV

sodium-potassium pump

a carrier protein that uses ATP to actively transport sodium ions out of a cell and potassium ions into the cell

Depolarization

Occurs with the Sodium channel opens and sodium rushes into the neuron

Repolarization

Period during which potassium ions diffuse out of the neuron

refractory period

The time when the sodium-potassium pump is most active to return the neuron to resting potential

resting potential

the state of the neuron when not firing a neural impulse

frontal lobe

associated with reasoning, planning, parts of speech, movement, emotions, and problem solving

parietal lobe

receives sensory input for touch and body position

occipital lobe

A region of the cerebral cortex that processes visual information

temporal lobe

A region of the cerebral cortex responsible for hearing and language.

Cerebellum

A large structure of the hindbrain that controls fine motor skills.

Pons

A brain structure that relays information from the cerebellum to the rest of the brain

brain stem

Connection to spinal cord. Filters information flow between peripheral nervous system and the rest of the brain.

medulla oblongata

Part of the brainstem that controls vital life-sustaining functions such as heartbeat, breathing, blood pressure, and digestion.

corpus callosum

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

pituitary gland

master gland

Hypothalamus

an area of the brain that produces hormones that control: Body temperature. Heart rate. Hunger. Mood.

Synapse

A junction where information is transmitted from one neuron to the receiving structure

Neurotransmitters

chemical messengers that cross the synaptic gaps between neurons

Acetylcholine (ACh)

enables muscle action, learning, and memory

Serotonin

Primary mood neurotransmitter

Dopamine

a neurotransmitter that regulates fine motor movement, motivation, pleasure, and emotional arousal

Adrenaline

A hormone released into the bloodstream in response to physical or mental stress

Noradrenaline

concentration neurotransmitter

GABA

An inhibitory neurotransmitter in the brain.

Endorphins

natural, opiate-like neurotransmitters linked to pain control and to pleasure, released during exercise

SSRIs

selective serotonin reuptake inhibitors

Cerebral Palsy

A loss or deficiency of motor control with involuntary spasms caused by permanent brain damage present at birth

Meningitis

inflammation of the meninges of the brain and spinal cord

multiple sclerosis

myelin sheath destruction. disruptions in nerve impulse conduction

Epilepsy

chronic brain disorder characterized by recurrent seizure activity