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bioRxiv · 10.1101/2022.12.29.522264

A change in behavioral state switches the pattern of motor output that underlies rhythmic head and orofacial movements

Kleinfeld, D.·Liao, S.-M.
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Abstract

The breathing rhythm serves as a reference that paces orofacial motor actions and orchestrates active sensing. Past work reports that pacing occurs solely at a fixed phase relative to sniffing. We reevaluated this constraint as a function of exploratory behavior. Allocentric and egocentric rotations of the head and the electromyogenic activity of the underlying motoneurons for head and orofacial movements were recorded in free-ranging rats as they searched for food. We found that a change in state from foraging to rearing is accompanied by a change in the phase of muscular activation relative to sniffing, so that pacing now occurs at one of two phases. Further, head-turning is biased such that an animal gathers a novel sample of its environment upon inhalation. In toto, the coordination of active sensing has a previously unrealized computational complexity that, in principle, can emerge from hindbrain circuits with fixed architecture and credible synaptic time-delays.

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Kleinfeld, D., Liao, S.-M.. 2022-12-30. A change in behavioral state switches the pattern of motor output that underlies rhythmic head and orofacial movements. https://doi.org/10.1101/2022.12.29.522264

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