Stimulation frequency and visually evoked scalp potentials with brief flashes of light.

Recording of the visually evoked scalp potential (VESP) elicited with flash stimulation was completed in six subjects presenting with normal vision. From the four separate signals recorded over the visual cortex, it was concluded that stimulation frequency affects some of the components of the VESP. Accordingly, in studies of the VESP character, the influence of stimulation frequency is a critical factor which must be taken into account when analyzing the resultant activity.