Visual evoked potentials the through pattern reversal stimulation technique has been recorded in twenty-two healthy Korean volunteers to establish the normative data of this EMG laboratory.

The normal visual evoked response to pattern reversal is characterized by a constant major positive wave(P₁) and two negative waves of a lesser rate of appearance. The mean latency of the P₁ wave is 98.75±5.16 msec with an upper limit of 114.23 msec.

There is no significant latency difference between left and right eye stimulation, and the upper limit of the P₁ latency difference between the two eyes is 6.37 msec.

Since there is a relatively minor correlation between age and the P₁ latency, further study using many different age groups will be performed.