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

Area of Science:

• Neuroscience
• Motor Control
• Systems Neuroscience

Background:

• The cortex's role in postural equilibrium and intervention during major disturbances is debated.
• Understanding neural dynamics during unexpected perturbations is crucial for deciphering motor control mechanisms.

Purpose of the Study:

• To investigate neural activity patterns in the cortex during unexpected postural perturbations.
• To elucidate the role of the primary sensory (S1) and motor (M1) cortices in dynamic postural control.

Main Methods:

• Recorded neural activity in rat S1 and M1 cortices during unexpected perturbations.
• Utilized a dynamical systems model to analyze M1 activity and limb forces.
• Examined neuronal class responses to different perturbation characteristics.

Main Results:

• Unique neuronal classes in S1 and M1 differentially encode perturbation characteristics.
• Significant information gain was observed in M1, indicating higher-order computations.
• A low-dimensional manifold in M1 activity was identified, with distinct subspaces for different computations based on neural firing patterns.

Conclusions:

• The cortex, especially M1, is actively involved in postural control through sophisticated neural computations.
• Findings provide insights into how the cortex manages postural stability.
• This research informs future work on postural instability following neurological disease.