Neural connections and communication, and types of neurons

1. Neurons
AP Psych
Ch 3 pgs. 71-77
Mrs. Limoges

2. 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

3. Neurons:
– Dendrites receive impulse
– Send to soma (cell body)
– Action potential through axon (ions)
– The synapse at end (terminal buttons)
– Synaptic transmission of neurotransmitters

4. 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’t
fire

5. 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

6. Synaptic transmission
– Slows down the charge
– Message must pass synaptic cleft
– Terminal buttons release neurotransmitters as
chemical messages
– Ready to start again!

7. 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

9. 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

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

11. 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)