PSYCH 112 Lecture Notes - Lecture 3: Axon Hillock, Soliton, Myelin
Document Summary
Nervous system consists primarily of glia & neurons. Glia of pns: schwann cells: similar function to oligodendrocytes, satellite cells: perform functions similar to astrocytes, enteric glia: play role in digestive processing. The soliton model is limit to max frequency of a neuron"s signals membrane"s density & thickness- that runs down the axon. Autonomic nervous system controls our internal organs rather than musculoskeletal. Sympathetic nervous system: signals our organs to increase/decrease rate of operation (fight or flight) Parasympathetic nervous system: signals our organs to relax and resume their normal rate of operation: heart slows down, digestion picks up. Chemical synapses occur when neurons are connected end to end or in functional circuits: most synapses occur on the dendrites. Summation is the business of adding up the incoming excitation and inhibition: spatial summation is inputs from different locations, temporal summation makes neurons sensitive to the rate at which the threshold value is reached.
