TitleDimensionality and dynamics in the behavior of C. elegans.
Publication TypeJournal Article
Year of Publication2008
AuthorsStephens, GJ, Johnson-Kerner, B, Bialek, W, Ryu, WS
JournalPLoS Comput Biol
Date Published2008 Apr
KeywordsAnimals, Behavior, Animal, Caenorhabditis elegans, Computer Simulation, Gait, Locomotion, Models, Biological

A major challenge in analyzing animal behavior is to discover some underlying simplicity in complex motor actions. Here, we show that the space of shapes adopted by the nematode Caenorhabditis elegans is low dimensional, with just four dimensions accounting for 95% of the shape variance. These dimensions provide a quantitative description of worm behavior, and we partially reconstruct "equations of motion" for the dynamics in this space. These dynamics have multiple attractors, and we find that the worm visits these in a rapid and almost completely deterministic response to weak thermal stimuli. Stimulus-dependent correlations among the different modes suggest that one can generate more reliable behaviors by synchronizing stimuli to the state of the worm in shape space. We confirm this prediction, effectively "steering" the worm in real time.

Alternate JournalPLoS Comput. Biol.