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.
","abstract_html":"<p>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.</p>","abstract_has_math":false,"creators":["Avritzer, Sofia Caetano"],"institution":null,"degree_name":"Doctor of Philosophy (PhD)","degree_level":"Thesis","degree_discipline":null,"degree_department":null,"school":null,"contributors":["Gaby Maimon"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2026,"date_issued":"2026-01-01T08:00:00Z","date_published":"2026-01-01T08:00:00Z","updated_at":"2026-07-24T04:11:55Z","subjects":["drosophila","neural circuits","navigation","central complex","working memory","inertial guidance","Life Sciences"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://digitalcommons.rockefeller.edu/student_theses_and_dissertations/837","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Gaby Maimon"]},{"key":"dc:creator","label":"Author","values":["Avritzer, Sofia Caetano"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2027-05-30T07:00:00Z"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Doctor of Philosophy (PhD)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["drosophila","neural circuits","navigation","central complex","working memory","inertial guidance","Life Sciences"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://digitalcommons.rockefeller.edu/student_theses_and_dissertations/837"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["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.
"]},{"key":"dc:title","label":"Title","values":["An Angular Working-Memory Signal that Guides Drosophila Navigational Trajectories"]}]}],"canonical_facts":{"dc:contributor":["Gaby Maimon"],"dc:creator":["Avritzer, Sofia Caetano"],"dc:date.available":["2027-05-30T07:00:00Z"],"dc:description.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.
"],"dc:identifier":["https://digitalcommons.rockefeller.edu/student_theses_and_dissertations/837"],"dc:subject":["drosophila","neural circuits","navigation","central complex","working memory","inertial guidance","Life Sciences"],"dc:title":["An Angular Working-Memory Signal that Guides Drosophila Navigational Trajectories"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["Doctor of Philosophy (PhD)"]},"updated_at":"2026-07-24T04:11:55Z"}