CAREER: Dissecting the Fundamental Components of Multi-input Response in Exploration and Navigation

University Of Miami, Coral Gables FL

Investigators

Abstract

A fundamental task of understanding physical systems is to determine how inputs are received, manipulated inside, and transformed into external outputs. This CAREER award investigates a living organism, the fruit fly larva, in a similar way, with the goal of characterizing how its simple brain and body operate to produce physical movement. Crawling larva traversing controlled environments that include changing temperature, vibration, and/or light level will be tracked with cameras, and their behavioral features determined precisely with computer video analysis. The study will use new methods that seek to predict the animal’s behavior in complex temperature environments, use a laser system to destroy single brain cells and observe the effect on behavior, simulate crawling to compare the larva to physics models, and determine how the larva handles multiple kinds of inputs at once. The results together will provide greater understanding of how living systems process the information in their environments and perform important actions. The research is also paired with education and outreach programs, which includes gathering data from student researchers around the world doing larva projects in physics courses, and an animal behavior art museum installation to reach a broader K-12 and public audience. With the goal of thoroughly understanding sensorimotor transformations in a step-by-step fashion, the experiments are designed to deliver complex stimulus functions to freely crawling Drosophila larvae, ideal animals for behavioral quantification and neuronal interrogation and manipulation. By characterizing the whole-animal response to a single input, temperature, as mathematical, predictive functions that maps input to output, the group will dissect the basic input elements that govern the rules of exploratory and navigational motion, and dissect the essential output elements that determine the overall diffusive and directed movement. Through fs laser ablation the group will selectively eliminate combinations of input circuit elements and observe the effect on behavior. They will also observe the whole-animal response to multiple input types: temperature, visible light, mechanical vibration, and optogenetic light. The work in this project will determine how multiple individual input elements in a stimulus circuit combine with internal parameters to produce behavior. In natural contexts animals must respond to many forms of inputs simultaneously, and a full understanding of living systems requires a comprehensive treatment that examines multiple stimuli, multiple sensory neurons acting in a circuit, and internal states and biases of individuals. Completion of the proposed work will make available to the scientific community a detailed characterization of how information travels through a living system, and how multiple inputs interact with each other to produce behavioral output. Determining how multiple inputs combine and especially how the weight of each input depends on surrounding conditions and history, will have direct bearing on more complex systems. Research will be integrated with an innovative education program that brings animal behavior experiments to physical sciences curriculum, and brings animal motion to an art context. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.