Figure 1.
Examples of steady-state PERGs recorded for each eye of a normal subject in response to a pattern of horizontal gratings (1.7 cy/deg, 99% contrast, 40 cd/m2 mean luminance, circular field size 25 deg diameter) alternating at 16.28 times/s or every 61.4 ms. The continuous lines represent the actual PERG waveforms (black, right eye; grey, left eye). The dashed waveforms superimposed on the PERG waveforms represent the harmonic components at the reversal frequency, isolated by means of Digital Fourier Transform (DFT). The amplitude and phase of DFT-isolated components represent the actual PERG measures.