Changes in visual evoked potentials observed in humans involved in cleanup work after the Chernobyl' catastrophe

We studied the parameters of visual evoked potentials (VEP) recorded in humans involved in the cleanup work after the Chernobyl' catastrophe and in persons of the control group. The VEP evoked by presentation of a reversing chessboard pattern were significantly modified in the group of cleanup workers: in many subjects their shape was drastically changed, the mean latent periods for P100 and N145 waves increased, and their amplitudes significantly dropped. The amplitude of the P200 component somewhat increased in the group of cleanup workers. Possible reasons for the observed changes in the evoked electrical activity and the mechanisms underlying the changes in the visual analyzer of the persons subjected to long-term irradiation are discussed.