title: Heterogeneous neural coding of corrective movements in motor cortex.
abstract: During a reach, neural activity recorded from motor cortex is typically thought to linearly encode the observed movement. However, it has also been reported that during a double-step reaching paradigm, neural coding of the original movement is replaced by that of the corrective movement. Here, we use neural data recorded from multi-electrode arrays implanted in the motor and premotor cortices of rhesus macaques to directly compare these two hypotheses. We show that while a majority of neurons display linear encoding of movement during a double-step, a minority display a dramatic drop in firing rate that is predicted by the replacement hypothesis. Neural activity in the subpopulation showing replacement is more likely to lag the observed movement, and may therefore be involved in the monitoring of the sensory consequences of a motor command.
authors.affiliation: Committee on Computational Neuroscience, University of Chicago Chicago, IL, USA.
authors.forename: Adam S
authors.initials: AS
authors.lastname: Dickey
authors.forename: Yali
authors.initials: Y
authors.lastname: Amit
authors.forename: Nicholas G
authors.initials: NG
authors.lastname: Hatsopoulos
mesh_terms: D000818:Animals; D003216:Conditioning, Operant / Q000502:physiology; D008253:Macaca mulatta; D009044:Motor Cortex / Q000502:physiology*; D009068:Movement / Q000502:physiology*; D009415:Nerve Net / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time / Q000502:physiology
keywords: double-step; motor cortex; neural coding; reaching; target jump