Modular deconstruction reveals the dynamical and physical building blocks of a locomotion motor program

Bruno, Angela�M.; Frost, William�N.; Humphries, Mark�D.

Abstract

The neural substrates of motor programs are only well understood for small, dedicated circuits. Here we investigate how a motor program is constructed within a large network. We imaged populations of neurons in the Aplysia pedal ganglion during execution of a locomotion motor program. We found that the program was built from a very small number of dynamical building blocks, including both neural ensembles and low-dimensional rotational dynamics. These map onto physically discrete regions of the ganglion, so that the motor program has a corresponding modular organization in both dynamical and physical space. Using this dynamic map, we identify the population potentially implementing the rhythmic pattern generator and find that its activity physically traces a looped trajectory, recapitulating its low-dimensional rotational dynamics. Our results suggest that, even in simple invertebrates, neural motor programs are implemented by large, distributed networks containing multiple dynamical systems.

Citation

Bruno, A., Frost, W., & Humphries, M. (2015). Modular deconstruction reveals the dynamical and physical building blocks of a locomotion motor program. Neuron, 86(1), (304-318). doi:10.1016/j.neuron.2015.03.005. ISSN 0896-6273

• Journal Article Type: Article
• Acceptance Date: Feb 25, 2015
• Online Publication Date: Mar 26, 2015
• Publication Date: Apr 8, 2015
• Deposit Date: Aug 6, 2018
• Publicly Available Date: Aug 6, 2018
• Journal: Neuron
• Print ISSN: 0896-6273
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 86
• Issue: 1
• Pages: 304-318
• DOI: https://doi.org/10.1016/j.neuron.2015.03.005
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S0896627315002019?via%3Dihub