title: Measurements of behavioral quiescence in Caenorhabditis elegans.
abstract: The nematode Caenorhabditis (C.) elegans, a long time work horse for behavioral genetic studies of locomotion, has recently been studied for quiescent behavior. Methods previously established for the study of C. elegans locomotion are not well-suited for the study of quiescent behavior. We describe in detail two computer vision approaches to distinguish quiescent from movement bouts focusing on the behavioral quiescence that occurs during fourth larval stage lethargus, a transition stage between the larva and the adult. The first is the frame subtraction method, which consists of subtraction of temporally adjacent images as a sensitive way to detect motion. The second, which is more computationally intensive, is the posture analysis method, which consists of analysis of the rate of local angle change of the animal's body. Quiescence measurements should be done continuously while minimizing sensory perturbation of the animal.
authors.affiliation: The institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637, United States.
authors.forename: Stanislav
authors.initials: S
authors.lastname: Nagy
authors.affiliation: Department of Neurology, Pereleman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, United States. Electronic address: raizen@mail.med.upenn.edu.
authors.forename: David M
authors.initials: DM
authors.lastname: Raizen
authors.affiliation: The institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637, United States; Department of Physics, James Franck Institute, The University of Chicago, Chicago, IL 60637, United States.
authors.forename: David
authors.initials: D
authors.lastname: Biron
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D017173:Caenorhabditis elegans / Q000235:genetics* / Q000502:physiology; D007814:Larva / Q000235:genetics / Q000502:physiology; D008124:Locomotion / Q000235:genetics / Q000502:physiology*
keywords: Elegans; Lethargus; Machine vision; Molting; Quiescence; Sleep