Visuomotor Responses in a Simple Animal Model: The Invertebrate Drosophila Melanogaster

Drosophila Melanogaster (DM) has been an undeniable vehicle for discovery in the past century. The fruit fly is an outstanding model in many laboratory contexts due to its flexibility, its relatively easy maintainment and the great degree of understanding of its biology. Nevertheless, their investigative potential is often overlooked or underutilized. This thesis investigates the multitude of applications of a specific DM-centered methodology, a movement-tracking systems on the subject in response to visual stimulation. In the present work, an important highlight is also put on the most notable fields that benefiting from the experiment, such as: Neural Circuit Mapping, Genetic Studies, Behavioral Plasticity and Memory, Biometric Design, Navigation Systems, Comparative Evolutionary Biology, and, not least, Toxicology. More specifically, my efforts are directed to provide instructions and insights on two experimental setups focusing on different kinds of visual stimulation and movement options, respectively referred to as Black Box and LED Arena. Both setups will be aimed at triggering and keeping track of an instinctive reaction in many animal models called OptoKinetic Reflex (OKR). The first setup immobilizes the fly, focusing on the head and wings movements in response to a Random Dots Motion kinematogram (kRDM). Conversely, the second one allows a limited rotational movement on the yaw axis, in an environment equipped with a rotating visual stimulation. The data gathered from these experiments is processed and analyzed through a pair of scripts based in Matlab, which will evaluate and distinguish the various phases of the OptoKinetic Reflex (OKR) by detecting the peak velocity and time duration of each saccade. The ultimate purpose of this thesis to offer a comprehensive description of the adopted experimental practices in great detail and discuss their potential applications in multiple branches of research.