Somatosensory Cortex Plays an Essential Role in Forelimb Motor Adaptation in Mice.
Our motor outputs are constantly re-calibrated to adapt to systematic perturbations. This motor adaptation is thought to depend on the ability to form a memory of a systematic perturbation, often called an internal model. However, the mechanisms underlying the formation, storage, and expression of such models remain unknown. Here, we developed a mouse model to study forelimb adaptation to force field perturbations. We found that temporally precise photoinhibition of somatosensory cortex (S1) applied concurrently with the force field abolished the ability to update subsequent motor commands needed to reduce motor errors. This S1 photoinhibition did not impair basic motor patterns, post-perturbation completion of the action, or their performance in a reward-based learning task. Moreover, S1 photoinhibition after partial adaptation blocked further adaptation, but did not affect the expression of already-adapted motor commands. Thus, S1 is critically involved in updating the memory about the perturbation that is essential for forelimb motor adaptation.
Center for Brain Science, Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA. Electronic address: mackenzie@post.harvard.edu.
Mackenzie Weygandt
MW
Mathis
Center for Brain Science, Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA.
Alexander
A
Mathis
Center for Brain Science, Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA. Electronic address: uchida@mcb.harvard.edu.
Naoshige
N
Uchida
D000222:Adaptation, Physiological / Q000502:physiology*; D000818:Animals; D005552:Forelimb / Q000502:physiology*; D007858:Learning / Q000502:physiology; D008297:Male; D051379:Mice; D009068:Movement / Q000502:physiology*; D013003:Somatosensory Cortex / Q000502:physiology*
force field adaptation; motor adaptation; mouse; optogenetics; primary somatosensory cortex; sensorimotor learning; sensory prediction error