Distinct spike discharges in the evoked cortical response of the light adapted cat

Abstract

Following adaptation to white background illumination, photic stimulation produced several spike-like discharges situated between the primary and secondary complexes. With fixed stimulus intensity and serially augmented levels of light adaptation these discharges were found to increase in amplitude. The potentials may be divided into two groups: early and late spikes. The former were produced at higher levels of light adaptation, the latter at a low levels of adaptation. Bilateral, ipsilateral and contralateral stimulation and light adaptation studies indicated that the discharges occurred only when the stimulus and adapting light were presented to the same eye. The discharges were affected by Nembutal administration.