Possible modulating influence of frontal cortex on nigro-striatal function.

1. After administration of (+)-amphetamine, rats with unilateral ablations of the frontal cortex rotated either ipsilaterally or contralaterally as a function of time after surgery.2. At early postoperative intervals (1-7 days), rotation was towards the side of the lesion.3. At later times (15-30 days), rotation was towards the intact side.4. Repeated testing with amphetamine appeared to slow the time-course of changes in rotational behaviour.5. These results suggest that a dopaminergic nigro-striatal system is modulated by the frontal cortex and that unilateral removal of the latter produces a denervation supersensitivity of the former.