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

• Published in: Cell reports (Cambridge) 2023-04, Vol.42 (4), p.112347-112347, Article 112347
• Main Authors: Disse, Gregory D., Nandakumar, Bharadwaj, Pauzin, Francois P., Blumenthal, Gary H., Kong, Zhaodan, Ditterich, Jochen, Moxon, Karen A.
• Format: Article
• Language: English
• Subjects: cortex; CP: Neuroscience; neural dynamics; neural trajectories; posture; rat
• ISSN: 2211-1247; 2211-1247
• DOI: 10.1016/j.celrep.2023.112347

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 separate subspaces enabled by congruent and incongruent neural firing patterns that define different computations 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. [Display omitted] •Cellular and population cortical dynamics are modulated by postural disturbances•Cortical computations for opposing limb movements lie in distinct latent subspaces•Non-overlapping neural trajectories emerge with suppression of opposing computations•These cortical dynamics can be used to decode single-trial corrective behaviors Disse et al. measured individual cortical neuronal responses to unexpected postural perturbations and demonstrated that cortical dynamics during opposing limb movements diverge into non-overlapping latent subspaces. This is achieved through the suppression of conflicting computations. These results suggest an important role of the cortex in postural control.