@article{18444, abstract = {Animals rely on compensatory actions to maintain stability and navigate their environment efficiently. These actions depend on global visual motion cues known as optic-flow. While the optomotor response has been the traditional focus for studying optic-flow compensation in insects, its simplicity has been insufficient to determine the role of the intricate optic-flow processing network involved in visual course control. Here, we reveal a series of course control behaviours in Drosophila and link them to specific neural circuits. We show that bilateral electrical coupling of optic-flow-sensitive neurons in the fly’s lobula plate are required for a proper course control. This electrical interaction works alongside chemical synapses within the HS-H2 network to control the dynamics and direction of turning behaviours. Our findings reveal how insects use bilateral motion cues for navigation, assigning a new functional significance to the HS-H2 network and suggesting a previously unknown role for gap junctions in non-linear operations.}, author = {Pokusaeva, Victoria and Satapathy, Roshan K and Symonova, Olga and Jösch, Maximilian A}, issn = {2041-1723}, journal = {Nature Communications}, publisher = {Springer Nature}, title = {{Bilateral interactions of optic-flow sensitive neurons coordinate course control in flies}}, doi = {10.1038/s41467-024-53173-w}, volume = {15}, year = {2024}, } @phdthesis{18568, abstract = {Locomotion is ubiquitous in the animal kingdom because an animal's survival depends on its ability to navigate its environment to find food, avoid predators and locate potential mates. These behaviours require control mechanisms that can extract information from the environment, particularly visual cues. Selective evolutionary pressures have thus refined such visuomotor transformations in a species-specific manner to meet the specific ecological and ethological challenges of each organism. However, a common challenge across organisms as visual information processing becomes increasingly detailed is the mechanisms required to synthesise disparate pieces of information into a coherent percept or unified picture of the world. In this thesis, I investigate how disparate visual information is combined in the brain of Drosophila melanogaster to effectively guide locomotion. For this, I first designed and built a behavioural setup to record locomotion and present visual stimuli to freely-walking fruit flies in a closed-loop manner. This setup allowed the investigation of innate visually-guided behaviours, including the optomotor reflex and courtship. Second, taking advantage of my system I investigated the optomotor response, a reflexive visual stabilisation behaviour in which flies turn in the direction of global motion to minimise retinal slip. This behaviour is thought to be mediated by Lobula plate tangential cells (LPTCs); a complex network of optic-flow-sensitive neurons essential for self-motion estimation. Using a novel genetic mutant, I demonstrate that electrical coupling between two LPTC subtypes, contralateral HS and H2 neurons, regulates the balance between smooth optomotor turning and saccadic anti-optomotor responses. These findings underscore the critical role of binocular motion cue integration in guiding course control. Finally, I developed a novel behavioural paradigm in which a sexually aroused male fruit fly is presented with an optomotor distractor. This setup creates competition between two visual behaviours, courtship tracking and the optomotor response, enabling me to explore how the visual system resolves this conflict. In this setting, males engaged in courtship selectively suppress their optomotor response based on the female's location. Furthermore, when this experiment is replicated with an “artificial female”, optogenetically aroused males alternate between tracking and optomotor responses. The probability and dynamics of this switching are determined by the relative strengths of the two competing stimuli. In summary, the results presented in this thesis explore two mechanisms – integration and competition - through which visual information is combined in the brain of the fruit fly to drive locomotion.}, author = {Satapathy, Roshan K}, isbn = {978-3-99078-047-3}, issn = {2663-337X}, pages = {114}, publisher = {Institute of Science and Technology Austria}, title = {{Mechanisms of visual integration and competition in innate behaviours in Drosophila melanogaster}}, doi = {10.15479/at:ista:18568}, year = {2024}, } @misc{17488, abstract = {Behavioural data for Pokusaeva, Satapathy et al. Relevant information can be found in the 'README.txt' file.}, author = {Satapathy, Roshan K and Jösch, Maximilian A and Symonova, Olga and Pokusaeva, Victoria}, keywords = {drosophila, behaviour, locomotion, gap junctions}, publisher = {Institute of Science and Technology Austria}, title = {{Bilateral interactions of optic-flow sensitive neurons coordinate course control in flies}}, doi = {10.15479/AT:ISTA:17488}, year = {2024}, } @techreport{8151, abstract = {The main idea behind the Core Project is to teach first year students at IST scientific communication skills and let them practice by presenting their research within an interdisciplinary environment. Over the course of the first semester, students participated in seminars, where they shared their results with the colleagues from other fields and took part in discussions on relevant subjects. The main focus during this sessions was on delivering the information in a simplified and comprehensible way, going into the very basics of a subject if necessary. At the end, the students were asked to present their research in the written form to exercise their writing skills. The reports were gathered in this document. All of them were reviewed by the teaching assistants and write-ups illustrating unique stylistic features and, in general, an outstanding level of writing skills, were honorably mentioned in the section "Selected Reports".}, author = {Maslov, Mikhail and Kondrashov, Fyodor and Artner, Christina and Hennessey-Wesen, Mike and Kavcic, Bor and Machnik, Nick N and Satapathy, Roshan K and Tomanek, Isabella}, pages = {425}, publisher = {IST Austria}, title = {{Core Project Proceedings}}, year = {2020}, }