Objectives: 

Several studies have shown the role of the putamen in movement activity as well as in reward processing. However, its specific function is not yet clear. Our aim was studying the neuronal activity of the putamen during the performance of a visuomotor task.

Materials: 

To do that, we trained a rhesus monkey (Macaca mulatta) to perform a task requiring a movement execution or a movement withholding. We used four abstract images as stimuli: 'Yes' images and 'No' images. 'Yes' images required pressing the lever to obtain reward while 'No' images required not pressing the lever and no reward was obtained. During some trials a stimulus called 'enhancer' was presented after the image onset. This stimulus indicated the occurrence of double reward for 'yes' images and double waiting until next trial for 'no' images. We used the ANOVA test to study the neuronal activity during the task performance.

Results: 

Preliminary data showed that some putamen neurons were modulated by some components of the task, such as enhancer onset, lever pressing, and reward onset.

Conclusions: 

This finding suggests that putamen could be involved in the processing of different types of stimuli.