title: Drosophila learn efficient paths to a food source.
abstract: Elucidating the genetic, and neuronal bases for learned behavior is a central problem in neuroscience. A leading system for neurogenetic discovery is the vinegar fly Drosophila melanogaster; fly memory research has identified genes and circuits that mediate aversive and appetitive learning. However, methods to study adaptive food-seeking behavior in this animal have lagged decades behind rodent feeding analysis, largely due to the challenges presented by their small scale. There is currently no method to dynamically control flies' access to food. In rodents, protocols that use dynamic food delivery are a central element of experimental paradigms that date back to the influential work of Skinner. This method is still commonly used in the analysis of learning, memory, addiction, feeding, and many other subjects in experimental psychology. The difficulty of microscale food delivery means this is not a technique used in fly behavior. In the present manuscript we describe a microfluidic chip integrated with machine vision and automation to dynamically control defined liquid food presentations and sensory stimuli. Strikingly, repeated presentations of food at a fixed location produced improvements in path efficiency during food approach. This shows that improved path choice is a learned behavior. Active control of food availability using this microfluidic system is a valuable addition to the methods currently available for the analysis of learned feeding behavior in flies.
authors.affiliation: Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673, Singapore.
authors.forename: Rapeechai
authors.initials: R
authors.lastname: Navawongse
authors.affiliation: Singapore Institute of Manufacturing Technology, 71 Nanyang Drive, Singapore 638075, Singapore.
authors.forename: Deepak
authors.initials: D
authors.lastname: Choudhury
authors.affiliation: Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673, Singapore.
authors.forename: Marlena
authors.initials: M
authors.lastname: Raczkowska
authors.affiliation: Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673, Singapore; Sieva Pte Ltd, Singapore.
authors.forename: James Charles
authors.initials: JC
authors.lastname: Stewart
authors.affiliation: Singapore Institute of Manufacturing Technology, 71 Nanyang Drive, Singapore 638075, Singapore.
authors.forename: Terrence
authors.initials: T
authors.lastname: Lim
authors.affiliation: Duke-NUS Medical School, 61 Biopolis Drive, Singapore 138673, Singapore.
authors.forename: Mashiur
authors.initials: M
authors.lastname: Rahman
authors.affiliation: Singapore Institute of Manufacturing Technology, 71 Nanyang Drive, Singapore 638075, Singapore.
authors.forename: Alicia Guek Geok
authors.initials: AG
authors.lastname: Toh
authors.affiliation: Singapore Institute of Manufacturing Technology, 71 Nanyang Drive, Singapore 638075, Singapore.
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673, Singapore; Duke-NUS Medical School, 61 Biopolis Drive, Singapore 138673, Singapore; Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 138673, Singapore. Electronic address: adamcc@gmail.com.
authors.forename: Adam
authors.initials: A
authors.lastname: Claridge-Chang
mesh_terms: D000818:Animals; D001307:Auditory Perception / Q000502:physiology; D001522:Behavior, Animal / Q000502:physiology*; D035841:Behavioral Research / Q000379:methods*; D004330:Drosophila / Q000502:physiology*; D004331:Drosophila melanogaster; D005502:Food; D065853:Spatial Learning / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology
keywords: Behavior; Drosophila; Drug screening; Feeding task; Flies; Learning assay; Skinner box