LSD EFFECT ON NEURON POPULATIONS IN VISUAL-CORTEX GAUGED BY TRANSIENT RESPONSES OF EXTRACELLULAR POTASSIUM EVOKED BY OPTICAL STIMULI

The effects of systemic LSD (10-25 μg/kg) on visually evoked [K+]o responses from the striate cortex have been investigated in cats. Elevation of [K+]o was dependent on the orientation, and direction of stimulus movement and showed ocular dominance. LSD most commonly produced a depression of [K+]o transients and a deterioration in their directional selectivity. These observations suggest that the effect of LSD is to produce a net depression in visually evoked neuronal firing. © 1979.