Psych_115_-_Dev_and_Chemical_Senses

Psych_115_-_Dev_and_Chemical_Senses - PSYCH 115: PRINCIPLES...

Info iconThis preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon
PSYCH 115: PRINCIPLES OF BEHAVIORAL NEUROSCIENCE Development and Chemical Senses Apr 21‘11
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Synaptogenesis After migration and differentiation, cells have to make connections with their appropriate target cells. As previously mentioned, it’s frequently the specificity of connections that defines the behavioral significance of any particular set of cells. After differentiation, neurons start sending their axons towards other cells and those axons sometimes have to travel great distances past many other cells to reach their targets.
Background image of page 2
Synaptogenesis Almost all neurons have been generated prior to birth, although some are still migrating to their final targets. However, the formation of the connections between cells occurs mostly post- natally. This suggest that both nature and nurture could guide synaptic formation.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Brain Development
Background image of page 4
Growth Cones How might “nature” govern synaptic connections? One idea is that cells secrete chemicals that either attract or repel particular axons that are en route to finding a target. In this way, chemoattractant or chemorepulsive molecules guide the formation of synaptic connections. Therefore, the idea is that two structures that are “destined” to be connected share a common chemical substrate that lays down the pathway between them.
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Synaptic and Cellular Loss But after all the cells in the brain have been generated and many connections have been formed, a second phase of synaptic loss and cell loss occurs. Most likely this allows us to generate many more connections that we need, followed by a selective elimination of those that just aren’t necessary.
Background image of page 6
Brain Development Many of these factors work in combination to result in the normally functioning adult brain. And many of these factors continue to function to refine synaptic connections in order to allow for plasticity in the adult brain that mediates learning and flexibility. The importance of these systems is demonstrated by the functional effects of abnormal brain development.
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
For example, consumption of alcohol during pregnancy can lead to obvious changes in brain anatomy. The upper left scan shows normal anatomy.
Background image of page 8
Image of page 9
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 06/13/2011 for the course PSYCH 115 taught by Professor Shaine during the Spring '07 term at UCLA.

Page1 / 36

Psych_115_-_Dev_and_Chemical_Senses - PSYCH 115: PRINCIPLES...

This preview shows document pages 1 - 9. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online