Sensory and Motor Information in Primary Motor Cortical Neurons During Arm Reaching To a Moving Target

Sensory information such as vision is essential to make movements. Primary motor cortex (M1) is connected to various parts of the brain and receives sensory information anatomically and functionally. However, it has not been much studied how motor cortical neurons process sensory information in limb movements. Thus, we analyzed the firing activity of primary motor cortical (M1) neurons in a monkey while it reached arms to grab a moving target. We could cluster M1 neurons into two classes depending on which type of information they encoded - kinematic or sensory information. From single neuron to multi neuron levels, these classes of neurons revealed different information and roles in reaching. Especially, divergence of their dynamical activities in a low-dimensional space showed distinguishable patterns - sensory information encoding neurons diverged earlier, followed by that of movement information encoding neurons depending on follow-up movement. Our results suggest that differences in roles and temporal windows whose neuronal clusters optimized were different among same cortical areas thus it needs to differentiate neuronal type in functionally when build BMI decoder.