Pain in the Assay: A Method for Measuring Olfactory Behavior in D. melanogaster

Presenters/Authors(s)

Abigail Long, Maggie Robertson, Hazem Attal, Farzaan Salman, Oliver Cook, Marryn Bennett

Abstract or Description

Behavioral assays allow researchers to probe the neural mechanisms underlying sensory processing. Drosophila melanogaster, the vinegar fly, is a common model for studying sensory processing, with several assays for studying odor-guided behavior. Behavioral assays vary in their reliability, cost effectiveness, and robustness, which affect interpretations across labs. Many researchers have therefore moved toward using elevator mazes, a two-choice olfactory assay, however there are limited studies comparing elevator mazes with other assays. Here, we developed our own elevator apparatus, assessed the impact of environmental conditions on olfactory sensitivity and compared elevators to another established assay. Of the environmental conditions tested, only sex and lighting affected olfactory responses. Our elevator design was optimized to create reusable apparatuses which require less preparation time and decrease time to trial completion, relative to other assays. We were also able to replicate reported concentration and odor-dependent attraction and aversion, as well as detect the impact of transgenic manipulations of neuronal function on olfactory sensitivity. Directly comparing our elevator assay to an established single fly video-tracking assay, we obtained the same robustness of behavior, although the elevator assay was more variable. However, the elevator assay was far faster, easier, and cost-effective than the video-tracking assay. Future applications of the elevator assay are to decrease variability and test other aspects of the neural mechanisms underlying olfactory choice.