The effect of binocular summation on time domain transient VEP wave's components

To determine the effect of binocular summation on the time domain transient VEP wave's components. The monocular and binocular transient visual evoked potentials of 21 normally vision volunteers 18 to 24 years (mean ± SD, 20.7 ± 1.9) during a reversing checkerboard stimulus with spatiotemporal frequency of 2.18-4 cpd-Hz were recorded. The amplitude and latency of N75, P100 and N135 components of monocular and binocular transient visual evoked potentials were measured. To evaluate the binocular summation for binocular records in compare to monocular ones, the average of right and left eyes results obtained and binocular findings were compared with averages of monocular ones using the statistical methods of paired t-test. latencies of N75, P100 and N135 components during binocular stimulation records were significantly shorter compared to monocular ones (p<0.005). The amplitudes of all of three components in binocular stimulation records were higher than monocular records (p<0.05). Regardless of its cause, the higher amplitude and lower latency during binocular stimulation compared to monocular records shows more cortical activity in a faster manner during binocular vision compared to monocular vision.