UC San Diego

Learning is a fundamental experience-dependent process involving permanent changes in behaviors. Among all learning processes, anti-instinctive learning, an ability to modify one's innate behaviors in ways that go against one's innate tendency, can confer great evolutionary advantages to animals and enable them to better adapt to the changing environment. Yet, our understanding of anti-instinctive learning and its underlying mechanisms is still limited. In this dissertation, I describe a new learning behavior of the fruit fly, which also identifies a second anti-instinctive learning behavior in the fly. This learning paradigm requires fruit fly to respond to a recurring, aversive, mild heat stress by modifying its innate locomotion behavior. Chapter 1 of this dissertation reviews definitions of behavior with a focus on locomotion, and the effects of learning on behaviors. Chapter 2 of this dissertation describes the design of a novel behavioral apparatus, the LaserSync system, used in this study. Chapter 3 of this dissertation describes the wild type fruit fly's anti-instinctive learning behaviors. Chapter 4 of this dissertation describes the exploration of the molecular and cellular mechanisms underlying anti-instinctive learning behavior. We found that experiencing movement-triggered heat stress repeatedly significantly reduced walking activity in wild type flies, indicating that fruit flies are capable of anti-instinctive learning. Based on this new learning behavior, we explored potentially relevant molecular and neuronal mechanisms underlying anti-instinctive behavior. This work is an effort to develop an animal model of anti-instinctive learning behavior that allows for rigorous interrogation of the underlying biological mechanisms. Insights generated from this study will bring us closer in understanding the biology of learning, and perhaps higher cognitive functions in general.