Frontal-striatal control of behavioral inhibition in the rat.

The direct application of crystalline dopamine, D-amphetamine or scopolamine in microgram quantities to the ventral anterior region of the corpus striatum (VAS) of rats increased their responding for food on a modified DRL-30 sec schedule of reinforcement. Similar applications of norepinephrine were less effective than dopamine, while the anticholinesterase eserine depressed responding. Electrolytic lesions of the ventrolateral, but not the dorsomedial, prefrontal cortex of rats also increased their response rates. These results were interpreted as being consistent with the idea of a dopamine-acetylcholine antagonism in the VAS whose net output modulate behavioral inhibition. This striatal mechanism may be influenced by the ventrolateral prefrontal cortex.