PSYCH101 Lecture Notes - Lecture 5: Myelin, Synaptic Pruning, Multiple Sclerosis

• School: University of Waterloo
• Department: Psychology
• Course: PSYCH101
• Professor: Paul Wehr

Document Summary

Nerve cells relay information in the form of electrical impulses throughout the nervous system. They send messages to other neurons, organs, muscles, and glands. They receive messages from other neurons and sensory cells. They integrate information (decide when to fire / activate action potential). Glial cells support nerve cells and compose 90% of all cells in nervous system. Astrocytes facilitate the formation of synapses (location where a cell can communicate with another cell). Dendrites receive information from other neurons or sensory organs. An axon connects neuron to other neurons further downstream. The myelin sheath insulates axons and increases conduction rate (prevents signals from jumping from one neuron to another). Multiple sclerosis happened due to the degeneration of the myelin sheath which causes the less of sensation, paralysis, and poor coordination. Neurons are called white matter if they have a myelin sheath and grey matter if they do not.