Amphetamine-induced recovery of visual cliff performance after bilateral visual cortex ablation in cats: measurements of depth perception thresholds.
After bilateral visual cortex ablation, cats exhibit a loss of depth perception as measured on a visual cliff, which recovers following administration of d-amphetamine. In this Study, 3 amphetamine-treated cats with visual cortex ablations showed a rapid and enduring recovery, with 2 of these animals obtaining levels of performance seen only with binocular vision, suggesting a restoration of binocular depth perception. Cats with asymmetrical lesions showed only a transient improvement during amphetamine treatment, and some animals not displaying autonomic signs of amphetamine intoxication did not improve. Saline-treated cats showed no signs of improvement, and the effect of amphetamine was blocked by the catecholaminergic antagonist haloperidol. These results indicate that amphetamine can induce an enduring recovery from a behavioral deficit after brain injury, which if left untreated would not spontaneously recover.