Abstract
Motor planning plays a critical role in producing fast and accurate movement. Yet, the neural processes that occur in human primary motor and somatosensory cortex during planning, and how they relate to those during movement execution, remain poorly understood. Here we used 7T functional magnetic resonance imaging (fMRI) and a delayed movement paradigm to study single finger movement planning and execution. The inclusion of no-go trials and variable delays allowed us to separate what are typically overlapping planning and execution brain responses. While our univariate results show widespread deactivation during finger planning, multivariate pattern analysis revealed finger-specific activity patterns in contralateral primary somatosensory cortex (S1), which predicted the planned finger movements. Surprisingly, these activity patterns were similarly strong to those found in contralateral primary motor cortex (M1). Control analyses ruled out the possibility that the detected information was simply an artifact of subthreshold movements during the preparatory delay. Furthermore, we observed that finger-specific activity patterns during planning were highly correlated to those during movement execution. These findings reveal that motor planning activates the specific S1 and M1 circuits that are engaged during the execution of a finger movement – while activity in the rest of S1 and M1 is suppressed. We propose that preparatory states in S1 may improve movement control through changes in sensory processing or via direct influence of spinal motor neurons.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
Disclosures. The authors declare no conflicts of interest.