Neural ensemble dynamics in trunk and hindlimb sensorimotor cortex encode for the control of postural stability

The cortex has a disputed role in monitoring postural equilibrium and intervening in cases of major postural disturbances. Here, we investigate the patterns of neural activity in the cortex that underlie neural dynamics during unexpected perturbations. In both the primary sensory (S1) and motor (M1) cortices of the rat, unique neuronal classes differentially covary their responses to distinguish different characteristics of applied postural perturbations; however, there is substantial information gain in M1, demonstrating a role for higher-order computations in motor control. A dynamical systems model of M1 activity and forces generated by the limbs reveals that these neuronal classes contribute to a low-dimensional manifold comprised of sepa-rate subspaces enabled by congruent and incongruent neural firing patterns that define different computa-tions depending on the postural responses. These results inform how the cortex engages in postural control, directing work aiming to understand postural instability after neurological disease.

Automated summary

This study investigates the patterns of neural activity in the cortex during unexpected perturbations and identifies unique neuronal classes that differentiate different characteristics of applied postural perturbations. These findings provide insights into how the cortex engages in postural control and can contribute to understanding postural instability after neurological disease.