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bioRxiv · 10.1101/2023.05.12.540432

Phototaxis is a state-dependent behavioral sequence in Hydra vulgaris

Kim, S.·Robinson, J. T.
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Abstract

Understanding how internal states like satiety are connected to animal behavior is a fundamental question in neuroscience. Hydra vulgaris, a freshwater cnidarian with only eleven neuronal cell types, serves as a tractable model system for studying state-dependent behaviors. We find that starved Hydra consistently moves toward light, while fed Hydra do not. By modeling this behavior as a set of three sequences - head orientation, jump distance, and jump rate -we demonstrate that the satiety state only affects the rate of the animal jumping to a new position, while the orientation and jump distance are unaffected. These findings yield insights into how internal states in a simple organism, Hydra, affect specific elements of a behavior, and offer general principles for studying the relationship between state-dependent behaviors and their underlying molecular mechanisms.

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Kim, S., Robinson, J. T.. 2023-05-13. Phototaxis is a state-dependent behavioral sequence in Hydra vulgaris. https://doi.org/10.1101/2023.05.12.540432

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