Drosophilalearn 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 indicates that improved path choice is a learned behavior; the other foraging metrics examined showed no evidence of learning. 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. D E

A Taste Circuit that Regulates Ingestion by Integrating Food and Hunger Signals

“…No existing fly feeding assay measures real-time ingestion by single flies at high resolution (Cognigni et al, 2011; Deshpande et al, 2014; Edgecomb et al, 1994; Navawongse et al, 2015). The proboscis extension assay measures the likelihood that a fly will extend its proboscis in response to food (Shiraiwa and Carlson, 2007).…”

Neuroscience Research using Small Animals on a Chip: From Nematodes to Zebrafish Larvae

“…Freely moving adult fruit flies inside the microfluidic channels were used to record their oviposition behavior where adult flies laid eggs on their preferential sites on a chemical-induced PDMS substrate (Fig. 4b) [7], and food-finding behavior [57]. Larvae of Danio rerio is also an important animal model that is used to study behavior responses.…”

“…A group of researchers studied oviposition (i.e., egg-laying) of the adult fruit fly [7,70]. Adult fruit fly has also been studied for observing how they and choose and approach the path for the food [7,57]. Danio rerio larvae have been used for behavioral studies as well.…”