HEMIRETINAL CONTRIBUTION TO THE TIMING OF THE FULL-FIELD PVEP AS DETERMINED WITH THE MOTOR REACTION-TIME

With the use of the simple motor reaction time (RT), we examined the c ontribution of the hemiretinas to the timing of the pattern reversal v isual evoked potential (PVEP), RTs were obtained to the reversal of a progressively dimmer check falling either on the central, nasal, tempo ral, superior or inferior retina, Results were correlated with the pea k time of the P-1 wave evoked to the reversal of the entire checkerboa rd stimulus to the same luminance conditions as that used to generate the RT measurements. Our results clearly indicate that the time taken to trigger a manual response depends not only on the luminance of the stimulus, but also on where it fans on the retina. Comparing the above data with the peak time of the PVEP obtained to the reversal of the e ntire screen indicates that at brighter luminance the peak time of the P-1 wave correlates with that measured from the most central retina, while at dimmer intensities it correlates with the mathematical averag e of all the retinal locations tested. (C) 1997 Elsevier Science Ltd.