Citation

Bruno AM, Frost WN, Humphries MD. Neuron 2015; 86(1): 304-318.

Affiliation

Faculty of Life Sciences, University of Manchester, Manchester, M13 9PT, UK. Electronic address: mark.humphries@manchester.ac.uk.

Copyright

(Copyright © 2015, Cell Press)

DOI

10.1016/j.neuron.2015.03.005

PMID

25819612

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.

Language: en