Recent studies have identified rotational dynamics in motor cortex (MC) which many assume arise from intrinsic connections in MC. However, behavioural and neurophysiological studies suggest that MC behaves like a feedback controller where continuous sensory feedback and interactions with other brain areas contribute substantially to MC processing. We investigated these apparently conflicting theories by building recurrent neural networks that controlled a model arm and received sensory feedback from the limb. Networks were trained to counteract perturbations to the limb and to reach towards spatial targets. Network activities and sensory feedback signals to the network exhibited rotational structure even when the recurrent connections were removed. Furthermore, neural recordings in monkeys performing similar tasks also exhibited rotational structure not only in MC but also in somatosensory cortex. Our results argue that rotational structure may also reflect dynamics throughout the voluntary motor system involved in online control of motor actions.
Upon publication the neural network code will be made publicly available athttps://github.com/Hteja/CorticalDynamics. Data and analysis code will be made publicly available at https://github.com/kevincross/CorticalDynamicsAnalysis.
Data from: Area 2 of primary somatosensory cortex encodes kinematics of the whole armhttps://creativecommons.org/publicdomain/zero/1.0/.
- Stephen H Scott
- Egidio Falotico
- Egidio Falotico
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: Studies were approved by the Queen's University Research Ethics Board and Animal Care Committee (#Scott-2010-035)
- Jesse H Goldberg, Cornell University, United States
© 2021, Kalidindi et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.