NeuronsAP Psych

Ch 3 pgs. 71-77

Mrs. Limoges

Neurons

– Sensory – give info TOWARD the brain

– afferent

– Motor – take info AWAY from brain

– efferent

– Interneurons communicate between M and S.– Brain

– Spinal cord

S

I

M

Neurons:

– Dendrites receive impulse

– Send to soma (cell body)

– Action potential through axon (ions)

– The synapse at end (terminal buttons)

– Synaptic transmission of neurotransmitters

Neurons

– Dendrites collect info from direct stimulation OR neighboring neurons

– Undergo subtle modifications

– Soma contains nucleus and life-support, executive job of assessing all messages

– Excitatory: fire

– Inhibitory: don’t fire

Fire

Don’tfire

Action Potential

– Stimulus, soma excited, axon ‘fires’

– Chemical ions give axon a charge (slightly negative is resting potential)

– Action potential reverses charge to positive briefly (dominoes)

– Fire or don’t fire: all or none

– Less than one-hundredth of a second

Synaptic transmission

– Slows down the charge

– Message must pass synaptic cleft

– Terminal buttons release neurotransmitters as chemical messages

– Ready to start again!

Neurotransmitters

– Synaptic vesicles rupture and release chemicals into cleft

– Special receptors fit certain neurotransmitters

– Break down and recycle…some after fitting, some never get ‘used’

– Reuptake draws them back into the vesicles

– Dopamine, serotonin, norepinephrine, acetylcholine, GABA, Glutamate, and Endorphins

Plasticity– Ability to change…make new connections or strengthen old ones

– Adapt and modify the organ/structure as result of experience! COOL– Compensate for injury

– Braille readers, violin players, taxi drivers

– Post-traumatic stress disorder

Glial Cells

– Used to think of “glue”– Structural support for neurons– Form a myelin sheath to insulate, speed up

conduction

Dendrite Dance

– Receiving Dendrites: Left hand = jazz hand

– Shake your soma (shoulders)

– Wave your axon (Right arm)

– Sprinkle those neurotransmitters to your neighbors (wiggle your right hand fingers)