University:
Kentucky State University
Course:
BIO 303 | Human Physiology
Academic year:

2021
Views:

305

Pages:

14
Author:

ge1mu2k1rrs

Neuronal Processing 112 Relaying Signals through Neuronal Pools 113 Neuronal Pools ➢ groups of neurons with special characteristics of organization ➢ comprise many different types of neuronal circuits ➢ converging ➢ diverging ➢ reverberating 114 Neuronal Pools: Localization of sensory Information modification 115 116 Neuronal Pools: Modification of Localization: Sharpening of signals Lateral inhibition 117 Lateral Inhibition  Sharpening of sensation. ◼ When a blunt object touches the skin, sensory neurons in the center areas are stimulated more than neighboring fields. ◼ Stimulation will gradually diminish from the point of greatest contact, without a clear, sharp boundary.  Will be perceived as a single touch with well defined borders. ◼ Occurs within CNS. 118 Lateral Inhibition in the sensory System as a way of sharpening of the stimulus Reverberating Circuits: prolongation of Time of the signals 120 The Organization of Neuronal Pools Neural Circuits 123 Other mechanisms for prolongation of time   Synaptic afterdischarge: since the time of EPSP (15-20 msec) is longer than the time of AP(0.1 – 10 msec) then more No. of AP per one EPSP Parallel circuits 124 Stabilization of neuronal discharge   Synaptic fatigue: short term and acute adjustment of sensitivity Neuronal inhibitory circuits: ◼ ◼  Gross inhibition –Basal ganglia inhibits muscle tone Feed back inhibition-Cortico-fugal fibers from cerebral cortex descending fibers to control the intensity and sharpness Downregulation and upregulation- Long term stabilization through modification of the receptor availability (internalization or externalization) 125