PSYC 355 Lecture Notes - Lecture 8: Synaptic Pruning, Synaptogenesis, Neurogenesis

• School: University of Maryland
• Department: Psychology
• Course: PSYC 355
• Professor: Elizabeth Redcay

Document Summary

10:1 glia to neuron ratio: methodological issues lead to this error. 5) child"s environment affects child"s genotype: epigenetic mechanisms alter functioning of the gene, environmental stimuli has direct affect on child"s genotype. Prenatal & postnatal: synaptogenesis (form connections with one another, myelination (improving connection speed) Primarily postnatal: synaptic pruning (refining connections) 27 weeks = 1/3 size of adult brain. Synaptogenesis and myelination increases brain size in adults compared to newborns: synapse formation (including dendritic arborization) Synaptogenesis & synaptic pruning: starts prenatally, form more synapses than needed during early peak. One just over powers thee other at different times. 2 phases of brain wiring: 1. Major structures forming connections, forming basic structure (building telephone lines, building freeways: 2. Building more specific connections from the major basic structure previously formed. (adding new dendrites) If connections are correct and being used they are strengthened, if not they are lost: myelination.