[Visual evoked potentials (VEPs) by leadings on scalp and dura in rabbits]

Visual evoked potentials (VEPs) were obtained from five rabbits. Responses to the photic stimulation were recorded by leading on scalp and dura. Stimulating conditions were changed in order of binocular, monocular (left and right) and screened binocular. The VEP waveforms leading on scalp and dura were composed of five positive and four negative peaks. The amplitude of the VEP leading on dura was about five times larger than that of the VEP leading on scalp. The VEP evoked by the monocular stimulation was characterized by the decreased amplitude in the ipsilateral hemisphere to the stimulated eye. It is furthermore characteristic in the dural recording that the major negative peaks in the early component disappeared in the same side as the stimulated eye. These differences in the VEP evoked by the monocular stimulation might reflect that the most projection of optic nerve cross at the optic chiasm in rabbits.