Nixon P D, Passingham R E
Department of Experimental Psychology, University of Oxford, United Kingdom.
Behav Neurosci. 1998 Jun;112(3):719-24. doi: 10.1037//0735-7044.112.3.719.
Monkeys (Macacca fascicularis) were tested for their ability to perform learned, self-initiated arm movements for reward, both before and after receiving bilateral putamen lesions. The rate at which they made the movements was significantly reduced postoperatively, but their performance on a visually cued control task was normal. It is argued that the impairment was not a consequence of poor motor control or motivation, but that it reflected a reduced capacity to recall learned movements in the absence of external cues. The results complement similar findings for monkeys with supplementary motor cortex (SMA) lesions; the putamen is interconnected with the SMA in a cortico-striatal-thalamocortical loop.
