eprintid: 10203628 rev_number: 10 eprint_status: archive userid: 699 dir: disk0/10/20/36/28 datestamp: 2025-03-14 07:54:53 lastmod: 2025-03-14 07:54:53 status_changed: 2025-03-14 07:54:53 type: thesis metadata_visibility: show sword_depositor: 699 creators_name: Fabre, Julie Marie Jacqueline title: Visual stimulus features are represented throughout the basal ganglia and potentiated by learning ispublished: unpub divisions: UCL divisions: B02 divisions: C07 divisions: D07 divisions: F85 note: Copyright © The Author 2025. Original content in this thesis is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) Licence (https://creativecommons.org/licenses/by-nc/4.0/). Any third-party copyright material present remains the property of its respective owner(s) and is licensed under its existing terms. Access may initially be restricted at the author’s request. abstract: The basal ganglia are a group of subcortical nuclei that play a crucial role in sensorimotor processing, learning, and decision-making. While the involvement of the basal ganglia in motor control has been extensively studied, their role in sensory processing and the transformation of sensory information along the basal ganglia pathway remains poorly understood. This thesis combines innovative technical developments with carefully designed behavioral experiments to investigate the propagation and modulation of visual information across the striatum, external globus pallidus (GPe), and substantia nigra pars reticulata (SNr) in mice. The first part of the thesis introduces novel tools and methodologies for optimizing the quality and stability of high-density extracellular recordings. These include Bombcell, a toolbox for assessing single-unit isolation; the Apollo implant, a reusable device for chronic recordings with Neuropixels probes; and UnitMatch, a robust algorithm for tracking neurons across sessions. These technical advancements enable reliable, long-term monitoring of neural activity across multiple basal ganglia nuclei. Leveraging these tools, the second part of the thesis characterizes the visual response properties and selectivity of neurons in the striatum, GPe, and SNr of naive and trained mice. In naive animals, visual information is propagated along the basal ganglia pathway, with a progressive decrease in selectivity from the striatum to downstream nuclei. Learning enhances visual responsiveness throughout the circuit while preserving this hierarchical organization. Furthermore, the behavioral context strongly modulates visual encoding, with the same stimulus evoking distinct activity patterns when associated with different actions. These findings highlight the role of the basal ganglia in integrating sensory and motor information, and provide insights into the computations performed by this circuit during sensorimotor learning and decision-making. The thesis lays the groundwork for future investigations into the neural basis of basal ganglia function and dysfunction. date: 2025-01-28 date_type: published full_text_type: other thesis_class: doctoral_embargoed thesis_award: Ph.D language: eng verified: verified_manual elements_id: 2353808 lyricists_name: Fabre, Julie lyricists_id: JFABR02 actors_name: Fabre, Julie actors_id: JFABR02 actors_role: owner full_text_status: restricted pagerange: 1-233 pages: 267 institution: UCL (University College London) department: Neuromuscular Diseases thesis_type: Doctoral citation: Fabre, Julie Marie Jacqueline; (2025) Visual stimulus features are represented throughout the basal ganglia and potentiated by learning. Doctoral thesis (Ph.D), UCL (University College London). document_url: https://discovery.ucl.ac.uk/id/eprint/10203628/1/PhD.pdf