The effects of phencyclidine on visually evoked potentials of rhesus monkeys

Phenyclidine (Sernylan) was given intramuscularly to 12 rhesus monkeys and electroencephalograms and visually evoked potentials to photic stimulation were recorded. Phencyclidine has profound effects upon VEP's, particularly a marked enhancement of positive components maximal around 100 msec after stimulus presentation. Most likely these effects are related to the level of surgical anesthesia, Stage III, phase I. A correlation was suggested between the increased amplitude of VEP's and the psychotic clinical manifestations of visual perceptual distortions. Physicians and investigators should be aware of the striking effects of this compound, now widely used as a street drug "angel's mist" of "angel's dust", on neurophysiological functions.