[Effect of deafferentation of the lateral geniculate body on its background activity]

Abstract

Elimination of reticular inputs to the lateral geniculate body (LGB) by sectioning of one half of the midbrain operculum, did not affect significantly the characteristics of the LGB evoked potential to light stimulus. At the same time LGB response to stimulation of the reticular formation by a single current impulse, though did not disappear completely, but changed greatly: its latency became twice as long, the negative component of the response was no more recorded. In conditions of LGB deafferentation, the characteristics of all rhythms of its electrical activity, besides the alpha-like one, considerably changed. At the same time, exactly this last rhythm underwent the greatest changes on the EEG of the visual cortex. On the basis of the obtained data it is suggested that the reticular formation takes a considerable and multiple part in generation of LGB rhythmic activity and that changes in its characteristics are clearly reflected in the ECoG rhythms formation. Retention of the LGB visual evoked potential and of the response to stimulation of the reticular formation after the section of one half of the midbrain operculum testifies to the presence of several reticular inputs to LGB.