Neural circuits - in general mature neurons are amitotic(do not divide if cell body remains intact regeneration is possible following injury the

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Neural circuits: functional groups of neurons that integrate incoming information from other sources & forward processed information to other sources - circuits: patterns of synaptic connections in neuronal pools - reflexes occur over neural pathways called reflex arcs - series circuit: one neuron stimulates the next in a sequence - diverging circuit: one presynaptic neuron stimulates several postsynaptic neurons - converging circuit: several presynaptic neuron stimulate one postsynaptic neuron - reverberating circuit: branches from later neurons in ciircuit stimulate earlier neurons; prolongs output signal - parralel after-discharge circuit : one presynaptic neuron stimulates several postsynaptic neurons which converge on one output neuron Regeneration of Nerve Fibers:
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: - in general, mature neurons are amitotic (do not divide)- if cell body remains intact, regeneration is possible- following injury, the two ends of neuron surrounding site of injury seal off & swell from accumulation of materials- Wallerian degeneration: the axon distal to the site of injury & its myelin sheath begins to disintegrate (debris cleaned up by macrophages & Schwann cells)- Schwann cells proliferate in response to macrophage signals, & express cell adhesion molecules & release growth factors to stimulate axonal growth. .. then, they guide axon extensions across the gap (form regeneration tube to bridge gap) & remyelinate the axon- The greater the distance between broken axon ends, the less the chance of Regeneration Page7...
View Full Document

This note was uploaded on 12/04/2011 for the course ANTHRO 2000 taught by Professor Monicaoyola during the Fall '10 term at Broward College.

Ask a homework question - tutors are online