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Discriminating External and Internal Causes for Heading Changes in Freely Flying Drosophila

As animals move through the world in search of resources, they change course in reaction to both external sensory cues and internally-generated programs. Elucidating the functional logic of complex search algorithms is challenging because the observable actions of the animal cannot be unambiguously...

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Autores principales: Censi, Andrea, Straw, Andrew D., Sayaman, Rosalyn W., Murray, Richard M., Dickinson, Michael H.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2013
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3585425/
https://www.ncbi.nlm.nih.gov/pubmed/23468601
http://dx.doi.org/10.1371/journal.pcbi.1002891
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author Censi, Andrea
Straw, Andrew D.
Sayaman, Rosalyn W.
Murray, Richard M.
Dickinson, Michael H.
author_facet Censi, Andrea
Straw, Andrew D.
Sayaman, Rosalyn W.
Murray, Richard M.
Dickinson, Michael H.
author_sort Censi, Andrea
collection PubMed
description As animals move through the world in search of resources, they change course in reaction to both external sensory cues and internally-generated programs. Elucidating the functional logic of complex search algorithms is challenging because the observable actions of the animal cannot be unambiguously assigned to externally- or internally-triggered events. We present a technique that addresses this challenge by assessing quantitatively the contribution of external stimuli and internal processes. We apply this technique to the analysis of rapid turns (“saccades”) of freely flying Drosophila melanogaster. We show that a single scalar feature computed from the visual stimulus experienced by the animal is sufficient to explain a majority (93%) of the turning decisions. We automatically estimate this scalar value from the observable trajectory, without any assumption regarding the sensory processing. A posteriori, we show that the estimated feature field is consistent with previous results measured in other experimental conditions. The remaining turning decisions, not explained by this feature of the visual input, may be attributed to a combination of deterministic processes based on unobservable internal states and purely stochastic behavior. We cannot distinguish these contributions using external observations alone, but we are able to provide a quantitative bound of their relative importance with respect to stimulus-triggered decisions. Our results suggest that comparatively few saccades in free-flying conditions are a result of an intrinsic spontaneous process, contrary to previous suggestions. We discuss how this technique could be generalized for use in other systems and employed as a tool for classifying effects into sensory, decision, and motor categories when used to analyze data from genetic behavioral screens.
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spelling pubmed-35854252013-03-06 Discriminating External and Internal Causes for Heading Changes in Freely Flying Drosophila Censi, Andrea Straw, Andrew D. Sayaman, Rosalyn W. Murray, Richard M. Dickinson, Michael H. PLoS Comput Biol Research Article As animals move through the world in search of resources, they change course in reaction to both external sensory cues and internally-generated programs. Elucidating the functional logic of complex search algorithms is challenging because the observable actions of the animal cannot be unambiguously assigned to externally- or internally-triggered events. We present a technique that addresses this challenge by assessing quantitatively the contribution of external stimuli and internal processes. We apply this technique to the analysis of rapid turns (“saccades”) of freely flying Drosophila melanogaster. We show that a single scalar feature computed from the visual stimulus experienced by the animal is sufficient to explain a majority (93%) of the turning decisions. We automatically estimate this scalar value from the observable trajectory, without any assumption regarding the sensory processing. A posteriori, we show that the estimated feature field is consistent with previous results measured in other experimental conditions. The remaining turning decisions, not explained by this feature of the visual input, may be attributed to a combination of deterministic processes based on unobservable internal states and purely stochastic behavior. We cannot distinguish these contributions using external observations alone, but we are able to provide a quantitative bound of their relative importance with respect to stimulus-triggered decisions. Our results suggest that comparatively few saccades in free-flying conditions are a result of an intrinsic spontaneous process, contrary to previous suggestions. We discuss how this technique could be generalized for use in other systems and employed as a tool for classifying effects into sensory, decision, and motor categories when used to analyze data from genetic behavioral screens. Public Library of Science 2013-02-28 /pmc/articles/PMC3585425/ /pubmed/23468601 http://dx.doi.org/10.1371/journal.pcbi.1002891 Text en © 2013 Censi et al http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.
spellingShingle Research Article
Censi, Andrea
Straw, Andrew D.
Sayaman, Rosalyn W.
Murray, Richard M.
Dickinson, Michael H.
Discriminating External and Internal Causes for Heading Changes in Freely Flying Drosophila
title Discriminating External and Internal Causes for Heading Changes in Freely Flying Drosophila
title_full Discriminating External and Internal Causes for Heading Changes in Freely Flying Drosophila
title_fullStr Discriminating External and Internal Causes for Heading Changes in Freely Flying Drosophila
title_full_unstemmed Discriminating External and Internal Causes for Heading Changes in Freely Flying Drosophila
title_short Discriminating External and Internal Causes for Heading Changes in Freely Flying Drosophila
title_sort discriminating external and internal causes for heading changes in freely flying drosophila
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3585425/
https://www.ncbi.nlm.nih.gov/pubmed/23468601
http://dx.doi.org/10.1371/journal.pcbi.1002891
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