Redundant information encoding in primary motor cortex during motor tasks

Information encoded in neuron ensembles has previously been hypothesized to be highly redundant, despite the apparent inefficiency of a redundant encoding system. The recent availability of intracortical, multi-electrode recordings has enabled the possibility of exploring how neuronal ensembles encode information as a whole. Applying concepts from information theory, we examined the redundancy of the target information encoded in both contralateral and ipsilateral hemispheres of the primary motor cortex (M1) in macaque monkeys performing a center-out reaching task. During movement, we reliably found neurons in contralateral M1 to contain higher target information and to be more redundant than ipsilateral M1 neurons, which is consistent with the conventional understanding that motor control is mainly governed by contralateral M1. Secondly, neuron ensembles in both hemispheres showed largely redundant information encoding. These results suggest that redundancy in information encoding is highly prevalent in the motor cortex and may contribute to proficient motor control.