PSY 201 Lecture Notes - Lecture 10: Reuptake, Sodium Channel, Schwann Cell
Document Summary
Astrocytes: multitaskers, stabilize nervous system and hold everything in place, hold onto capillaries. Protects brain from toxins in blood: clean up crew. Microglia: clean up dead cells in brain. Myelin: insulates axons, made by glial cells, oligodendrocytes (cns) Form scar tissue which causes problems with injuries in spinal cord: schwann cells (pns, myelin makes neurons more efficient, frontal lobe does not develop until 25. The action potential: sodium channels open, sodium enters neuron, potassium channels open, potassium leaves cell, sodium channels close, potassium channels close. Resting cell: has a resting potential like a battery: chemical messengers can trigger action potential, threshold: -55 to -65. All-or-none: you either get the signal or not, an action potential is an action potential. Must finish one action potential before you start another: relative refractory period. Not likely to: there is a limit to how many times neurons can fire per second, should be about 1000 a second.
