A psychophysical and electrophysiological platform using internal action selection task in primate parkinsonian model*

Internal action selection is an important motor control, in which patients with Parkinson's disease (PD) generally show deficiencies. Basal ganglia (BG) is proved to play an important role in decision-making and act as a specialized internal selection device within the vertebrate brain architecture. Furthermore, some studies showed there was a close relationship among striatal dopamine signaling, action selection and time interval by training mice to perform an internal selection task. However, the neural mechanism of the internal action selection is still unclear.In this study, we setup a platform for psychophysical and electrophysiological study and recorded behavioral data from normal human subjects and primates when they performing an internal action selection task. The results showed that longer trial intervals led to longer action transition time, which indicates the time interval biases internal action selection, and the effect of movement direction was not significant. Furthermore, we recorded the task-related neuronal activity in primate’s primary motor cortex (M1). Preliminary data showed there were significant firing rate changes in M1 at the transition of action selection.