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arXiv · 1603.04023

Resolving coiled shapes reveals new reorientation behaviors in C. elegans

Onno D Broekmans·Jarlath B Rodgers·William S Ryu·Greg J Stephens
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Abstract

We exploit the reduced space of C. elegans postures to develop a novel tracking algorithm which captures both simple shapes and also self-occluding coils, an important, yet unexplored, component of worm behavior. We apply our algorithm to show that visually complex, coiled sequences are a superposition of two simpler patterns: the body wave dynamics and a head-curvature pulse. We demonstrate the precise coiled dynamics of an escape response and uncover new behaviors in spontaneous, large amplitude coils; deep reorientations occur through classical Omega-shaped postures and also through larger, new postural excitations which we label here as delta-turns. We find that omega and delta turns occur independently, the serpentine analog of a random left-right step, suggesting a distinct triggering mechanism. We also show that omega and delta turns display approximately equal rates and adapt to food-free conditions on a similar timescale, a simple strategy to avoid navigational bias.

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Onno D Broekmans, Jarlath B Rodgers, William S Ryu, Greg J Stephens. 2016-03-13. Resolving coiled shapes reveals new reorientation behaviors in C. elegans. https://doi.org/10.7554/elife.17227

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