Reorganization between preparatory and movement population responses in motor cortex.
Neural populations can change the computation they perform on very short timescales. Although such flexibility is common, the underlying computational strategies at the population level remain unknown. To address this gap, we examined population responses in motor cortex during reach preparation and movement. We found that there exist exclusive and orthogonal population-level subspaces dedicated to preparatory and movement computations. This orthogonality yielded a reorganization in response correlations: the set of neurons with shared response properties changed completely between preparation and movement. Thus, the same neural population acts, at different times, as two separate circuits with very different properties. This finding is not predicted by existing motor cortical models, which predict overlapping preparation-related and movement-related subspaces. Despite orthogonality, responses in the preparatory subspace were lawfully related to subsequent responses in the movement subspace. These results reveal a population-level strategy for performing separate but linked computations.
Center for Theoretical Neuroscience, Columbia University, New York, New York 10032, USA.|Department of Neuroscience, Columbia University Medical Center, New York, New York 10032, USA.
Gamaleldin F
GF
Elsayed
Department of Neuroscience, Columbia University Medical Center, New York, New York 10032, USA.
Antonio H
AH
Lara
Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA.
Matthew T
MT
Kaufman
Department of Neuroscience, Columbia University Medical Center, New York, New York 10032, USA.|Grossman Center for the Statistics of Mind, Columbia University, 1255 Amsterdam Avenue, New York, New York 10027, USA.|David Mahoney Center for Brain and Behavior Research, Columbia University Medical Center, New York, New York 10032, USA.|Kavli Institute for Brain Science, Columbia University Medical Center, New York, New York 10032, USA.
Mark M
MM
Churchland
Center for Theoretical Neuroscience, Columbia University, New York, New York 10032, USA.|Grossman Center for the Statistics of Mind, Columbia University, 1255 Amsterdam Avenue, New York, New York 10027, USA.|Department of Statistics, Columbia University, 1255 Amsterdam Avenue, Room 1005 SSW, MC 4690, New York, New York 10027, USA.
John P
JP
Cunningham
D000818:Animals; D008253:Macaca mulatta; D008297:Male; D008959:Models, Neurological; D009044:Motor Cortex / Q000502:physiology*; D009068:Movement