Dorsal striatal lesions in rats. 2: Effects on spatial and non-spatial learning.

Rats with small electrolytic lesions of the dorsal striatum were evaluated in acquisition of spatial learning, sensorimotor learning, and a straight runway food approach response and its extinction. No differences were detected between rats with dorsal striatal lesions and sham-operated controls during acquisition of hidden and visible trials in the Morris water maze. Neither was an intergroup difference observed during acquisition of the rotorod test of motor coordination. Lesioned rats were not impaired in running for a food reward, but their running latencies on day 2 of extinction were lower than those of controls, an indication of perseveration. These results indicate that perseverative responding may occur in dorsal striatal lesioned rats in the absence of spatial or sensorimotor defects.