mbon
The Impact of Structural Changes on Learning Capacity in the Fly Olfactory Neural Circuit
Xie, Katherine, Ocker, Gabriel Koch
The Drosophila mushroom body (MB) is known to be involved in olfactory learning and memory; the synaptic plasticity of the Kenyon cell (KC) to mushroom body output neuron (MBON) synapses plays a key role in the learning process. Previous research has focused on projection neuron (PN) to Kenyon cell (KC) connectivity within the MB; we examine how perturbations to the mushroom body circuit structure and changes in connectivity, specifically within the KC to mushroom body output neuron (MBON) neural circuit, affect the MBONs' ability to distinguish between odor classes. We constructed a neural network that incorporates the connectivity between PNs, KCs, and MBONs. To train our model, we generated ten artificial input classes, which represent the projection neuron activity in response to different odors. We collected data on the number of KC-to-MBON connections, MBON error rates, and KC-to-MBON synaptic weights, among other metrics. We observed that MBONs with very few presynaptic KCs consistently performed worse than others in the odor classification task. The developmental types of KCs also played a significant role in each MBON's output. We performed random and targeted KC ablation and observed that ablating developmentally mature KCs had a greater negative impact on MBONs' learning capacity than ablating immature KCs. Random and targeted pruning of KC-MBON synaptic connections yielded results largely consistent with the ablation experiments. To further explore the various types of KCs, we also performed rewiring experiments in the PN to KC circuit. Our study furthers our understanding of olfactory neuroplasticity and provides important clues to understanding learning and memory in general. Understanding how the olfactory circuits process and learn can also have potential applications in artificial intelligence and treatments for neurodegenerative diseases.
- North America > United States > Massachusetts > Suffolk County > Boston (0.04)
- North America > Mexico (0.04)
Visual Homing in Outdoor Robots Using Mushroom Body Circuits and Learning Walks
Gattaux, Gabriel G., Serres, Julien R., Ruffier, Franck, Wystrach, Antoine
Ants achieve robust visual homing with minimal sensory input and only a few learning walks, inspiring biomimetic solu tions for autonomous navigation. While Mushroom Body (MB) models hav e been used in robotic route following, they have not yet been appli ed to visual homing. We present the first real-world implementation of a l ateralized MB architecture for visual homing onboard a compact autonom ous car-like robot. We test whether the sign of the angular path integ ration (PI) signal can categorize panoramic views, acquired during lea rning walks and encoded in the MB, into "goal on the left" and "goal on the r ight" memory banks, enabling robust homing in natural outdoor set tings. We validate this approach through four incremental experimen ts: (1) simulation showing attractor-like nest dynamics; (2) real-wor ld homing after decoupled learning walks, producing nest search behavior; (3) homing after random walks using noisy PI emulated with GPS-RTK; and (4) precise stopping-at-the-goal behavior enabled by a fifth MB Output Neuron (MBON) encoding goal-views to control velocity. This mi mics the accurate homing behavior of ants and functionally resemble s waypoint-based position control in robotics, despite relying solely on visual input. Operating at 8 Hz on a Raspberry Pi 4 with 32 32 pixel views and a memory footprint under 9 kB, our system offers a biologically grounded, resource-efficient solution for autonomous visual homing.
- Europe > France > Provence-Alpes-Côte d'Azur > Bouches-du-Rhône > Marseille (0.06)
- Europe > France > Occitanie > Haute-Garonne > Toulouse (0.05)
- Europe > France > Île-de-France > Paris > Paris (0.04)
- Health & Medicine (0.46)
- Information Technology (0.34)