Abstract
The purpose was to test the parameters of visual evoked potentials (VEPs), including the event-related variety (ERP), in deaf persons. Three types of visual stimuli (with dominating parvocellular or magnocellular system activation or with cognitive tasks) were used in the study.
Six deaf persons (4 women, 2 men, mean age 17 years) and 6 persons with normal hearing (sex- and age matched) were included in this pilot study. In all types of stimulation, latencies and amplitudes of main VEPs and ERPs components were evaluated.
No significant latency differences were found in VEPs even in ERPs. However, significantly reduced amplitudes were found in occipital area for motion stimuli (activating mainly magnocellular system) and for cognitive stimuli.
These findings might be due to functional reorganization of extrastriate and cognitive cortical areas of deaf subjects.