- Main
Multisensory functional and comparative analysis of object tracking in flying fruit flies
- Rimniceanu, Martha
- Advisor(s): Frye, Mark A
Abstract
The survival and success of animals across phyla is critically dependent on generating appropriate behavioral responses to visual cues that are often complex and ambiguous. Visual objects can represent predators, conspecifics, obstacles and navigational goals, and must be discriminated from moving panoramas whose spatial features can vary greatly across environments. Due to its high-performance demands, insect flight is an excellent system used to study the behavioral algorithms governing the detection and responses to moving objects, and their underlying neural mechanisms. Yet, much of our understanding of the neurobiology of object discrimination comes from highly restrictive preparations that limit or severely compromise the multisensory feedback that modulates visual circuits in freely behaving animals. This dissertation probes how robust and well-characterized object tracking behaviors can be modulated by both multisensory context and visual-ecological adaptations. We demonstrate that the absence of naturalistic body movement cues in classical body-fixed virtual reality paradigms relegates smooth optomotor responses typically reserved for gaze stabilization to object pursuit tasks. We show that this occurs through a simple gain modulation mechanism and propose the gyroscopic haltere proprioceptive circuit that play a role in actively damping visual circuits. We generate novel genetic reagents in D. melanogaster that allow targeted manipulation of haltere feedback and propose experiments to test the integration of proprioceptive and visual feedback in vivo. Finally, through comparative studies across Drosophila species, we demonstrate that the same object pursuit strategies that we found to be highly dependent on multisensory context are also shaped by the properties of the visual ecology. This series of studies can inform the design and interpretation of neurophysiological assays where parameters are necessarily restricted to probe neural mechanisms. More importantly perhaps, these studies illuminate general principles that expand our understanding of how locomoting animals process visual cues in relevant naturalistic contexts.
Main Content
Enter the password to open this PDF file.
-
-
-
-
-
-
-
-
-
-
-
-
-
-