Measurement of contrast sensitivity function using pattern-reversal visual evoked responses.

In order to determine whether pattern-reversal visual evoked response (VER) can be used to measure contrast sensitivity function (CSF), we investigated the effect of change of contrast upon pattern-reversal VER. Contrast thresholds for VER were extrapolated in five spatial frequencies. The CSF curve obtained from the VER showed the inverted U-shape as the psychophysical CSF curve. However, the low frequency fall-off that is usually seen in psychophysical CSF was less evident in the electrophysiological CSF. The difference between the electrophysiological CSF and the psychophysical CSF increased along with the spatial frequency. Proper stimulus conditions would make this method of evaluation of CSF by pattern reversal VER useful in relatively young children in whom psychophysical tests cannot be performed.