Date of Award
2025
Document Type
Thesis
Degree Name
Doctor of Philosophy (PhD)
Thesis Advisor
Gaby Maimon
Abstract
The navigational behavior of many species can be guided not just by immediate sensory input, but also by memories of the environment. In fruit flies, for example, neural signals in a well-studied brain region called the central complex help guide navigation. Previous work has shown that “compass neurons” in the central complex track the fly’s heading angle, while a second set of central complex neurons track the fly’s goal angle. The difference between the fly’s heading and goal angles is computed to produce a steering signal. I discovered that a third set of central complex neurons, called hΔA cells, integrate the fly’s recent traveling direction over a window of ~7-10 s, creating a working memory of the fly’s trajectory. This signal feeds into the circuit just described, promoting flies to continue walking in their recent traveling direction, like an inertia term for the steering circuit. We show that this inertia-like term contributes to a memory-based navigation task, complementing the role of the previously described goal signal in that task. Interestingly, the activity of hΔA neurons depends on behavioral context, dropping significantly in a task where trajectory inertia is unlikely to be helpful. The hΔA signal is built through a circuit motif that repeats a few times in the central complex. This recurring architecture might allow the fly brain to construct a range of memories and goals with distinct spatiotemporal properties that can be used during navigation.
Recommended Citation
Avritzer, Sofia Caetano, "An Angular Working-Memory Signal that Guides Drosophila Navigational Trajectories" (2025). Student Theses and Dissertations. 837.
https://digitalcommons.rockefeller.edu/student_theses_and_dissertations/837
Comments
A Thesis Presented to the Faculty of The Rockefeller University in Partial Fulfillment of the Requirements for the degree of Doctor of Philosophy