Neural Indices of Short-Term Visual Deprivation in Humans: Effects upon the Patterned VEP

The effects of seven hours of unilateral deprivation on the monocular and binocular patterned Visually Evoked Potential (pVEP) were investigated in thirty healthy, non-amblyopic subjects. Diverse results from the limited work published in this area prompted the study. The type of deprivation (form versus form and light deprivation), ocular dominance of the deprived eye and subject age were considered. For this group, the type of deprivation appeared to have no significant effect except when ocular dominance was considered. A decrease in the tran­sient VEP (tVEP) amplitude with a corresponding decrease in tVEP im­plicit time (IT) was found when the dominant eye was deprived of form and light. For the age range studied (11-24 year olds), subject age was not found to be an important factor. The temporary post-deprivation changes noted in the tVEP were attributed to a disruption in the mutual inhibition that normally occurs between ocular channels.