上丘の誘発電位に対する視覚領刺激の効果(<特集>脳と神経の研究IV)

概要

論文の詳細を見る
Adult cats (2.5 to 4kg in w.) were surgically operated under ether anesthesia. After ether administration was discontinued, the animal was immobilized with Flaxedil and artificially respirated. In these animals, the electrical responses of the stratum griseum superficiale of the superior colliculus (SC), elicited by stimulation of the optic nerve (ON), the visual cortex (VC) and the lateral geniculate body (GL), were studied. The results are as follows: 1) The existence of efferent pathway from VG to SG (cortico-collicular tract) is confirmed by means of electrophysiological manner. 2) The evoked potential responding to ON stimulation is recorded at SG. This potential shows three different components, Io, Ho and IIIo. These have different response times, respectively; Io=5msec, IIo=10msec and IIIo=50msec. IIo (middle component) is a summation of two different elements. One is directly carried by fine fibers (retinocollicular tract) and the other is indirectly (via GL, VG and cortico-collicular tract). These are direct and indirect pathway. 3) The neurons of SG receives the double influence from both direct and indirect pathways respectively. The indirect pathway acts to enhance the functions of direct pathway. 4) SG is said to be a control center for eye movements and this cortico-collicular tract could be assumed to work as a feedback system on retino-collicular tract.
千葉大学の論文