Abstract
The electric response of the optic lobe to retinal stimulation by light was observed in the isolated brain-eyeball-preparation of toad.
1. The response consisted of two or three main waves which are first negative monophasic or first diphasic with initial positive abrupt and a series of successive monophasic waves. But these wave forms showed remarkably seasonal variations. In a hibernation toad the response con-sisted of only two or three large waves.
2. Such complicated waves as seen in summer toads are simplified by repetitive stimulation of a certain frequency into only two or three waves.
3. Strychnine facilitates the activity, especially that of the elements which respond in the beginning.
4. According to these findings, it appears that two or three main waves show the activities of the afferent terminals while a series of suc-cessive waves show the activities of the synaptic process and motor cells.
