AP Psych - neurons and neuro impulses

neuron

nerve cell

dendril

fibers that receive information

axon

fibers that send info to other neurons, muscles, and glands (very long)

myelin sheath

fatty tissue which insulates axon and helps speed up impulses; multiple sclerosis is when it deteriorates

impulses

travel between 2 to 200 mph

cell body

mitochondria turns glucose into energy for cell life support

action potential

electrical charge that travels down an axon

ions

electrically charged atoms

polarized

resting axon is more negative on the inside and more positive on the outside

selectively permeable

axon is selective about what it allows in

depolarization

gates open along axon and allow positive ions to flow in (Na+)

threshold

the level of stimulation required to trigger a neural impulse

self-propogating

one part depolarizes causing the next channel to open (like falling dominoes)

all or none

a neuron either fires completely or does not fire at all

refractory period

after firing, the neuron must recharge. positive potassium (K+) flows out and the neuron becomes repolarized. this process occurs up to 1000 times per sec

neural communication synapse

gap between the neurons

axon terminals

contain vesicles/sacs which release chemicals across the gap

neurotransmitters

chemicals that cross the synapse and bind with receptors on dendrites of the next neuron

reuptake

excess neurotransmitters are reabsorbed back into the vesicles

agonist

acts like the neurotransmitter and binds with the receptor (tricks brain)

antagonist

blocks receptor so that neurotransmitter can't stimulate receptor or may inhibit release of neurotransmitter (like ibuprofen)

lock and key

neurotransmitters have a certain shape, only fit with certain dendrites

blood brain barrier

brain screens out unwanted chemicals circulating in the blood; dopamine won't cross the barrier but L-Dopa (agonist) will (used for Parkinson's)

neural networks

clusters of neurons working together to accomplish the same task (work as a group)

afferent

bring pain inward, sensory

efferent

reflex, pain signal sent to spine, makes one synapse around spine/nerve, goes back to hand/where it occurre, when pain is bad, bring pains outward, motor

chemicals used in depolarizing process

sodium, calcium, potassium

order energy travels

dendrite, cell body, axon

excitatory

tells rest to fire

inhibatory

goes across synapse into lock and key, tells not to fire

central nervous system

incased in bone, brain and spinal cord

peripheral nervous system

outside bone

somatic

motor and sensory, efferent and afferent

motor

nerves that allow you to move

sensory

5 senses

autonomic

controls all things in the body you don't have to think about

sympathetic

turns on fight or flight

parasympathetic

turns off fight or flight