--- _id: '12809' abstract: - lang: eng text: "Understanding the mechanisms of learning and memory formation has always been one of\r\nthe main goals in neuroscience. Already Pavlov (1927) in his early days has used his classic\r\nconditioning experiments to study the neural mechanisms governing behavioral adaptation.\r\nWhat was not known back then was that the part of the brain that is largely responsible for\r\nthis type of associative learning is the cerebellum.\r\nSince then, plenty of theories on cerebellar learning have emerged. Despite their differences,\r\none thing they all have in common is that learning relies on synaptic and intrinsic plasticity.\r\nThe goal of my PhD project was to unravel the molecular mechanisms underlying synaptic\r\nplasticity in two synapses that have been shown to be implicated in motor learning, in an\r\neffort to understand how learning and memory formation are processed in the cerebellum.\r\nOne of the earliest and most well-known cerebellar theories postulates that motor learning\r\nlargely depends on long-term depression at the parallel fiber-Purkinje cell (PC-PC) synapse.\r\nHowever, the discovery of other types of plasticity in the cerebellar circuitry, like long-term\r\npotentiation (LTP) at the PC-PC synapse, potentiation of molecular layer interneurons (MLIs),\r\nand plasticity transfer from the cortex to the cerebellar/ vestibular nuclei has increased the\r\npopularity of the idea that multiple sites of plasticity might be involved in learning.\r\nStill a lot remains unknown about the molecular mechanisms responsible for these types of\r\nplasticity and whether they occur during physiological learning.\r\nIn the first part of this thesis we have analyzed the variation and nanodistribution of voltagegated calcium channels (VGCCs) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid\r\ntype glutamate receptors (AMPARs) on the parallel fiber-Purkinje cell synapse after vestibuloocular reflex phase reversal adaptation, a behavior that has been suggested to rely on PF-PC\r\nLTP. We have found that on the last day of adaptation there is no learning trace in form of\r\nVGCCs nor AMPARs variation at the PF-PC synapse, but instead a decrease in the number of\r\nPF-PC synapses. These data seem to support the view that learning is only stored in the\r\ncerebellar cortex in an initial learning phase, being transferred later to the vestibular nuclei.\r\nNext, we have studied the role of MLIs in motor learning using a relatively simple and well characterized behavioral paradigm – horizontal optokinetic reflex (HOKR) adaptation. We\r\nhave found behavior-induced MLI potentiation in form of release probability increase that\r\ncould be explained by the increase of VGCCs at the presynaptic side. Our results strengthen\r\nthe idea of distributed cerebellar plasticity contributing to learning and provide a novel\r\nmechanism for release probability increase. " acknowledged_ssus: - _id: EM-Fac - _id: Bio - _id: PreCl alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Catarina full_name: Alcarva, Catarina id: 3A96634C-F248-11E8-B48F-1D18A9856A87 last_name: Alcarva citation: ama: 'Alcarva C. Plasticity in the cerebellum: What molecular mechanisms are behind physiological learning. 2023. doi:10.15479/at:ista:12809' apa: 'Alcarva, C. (2023). Plasticity in the cerebellum: What molecular mechanisms are behind physiological learning. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:12809' chicago: 'Alcarva, Catarina. “Plasticity in the Cerebellum: What Molecular Mechanisms Are behind Physiological Learning.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:12809.' ieee: 'C. Alcarva, “Plasticity in the cerebellum: What molecular mechanisms are behind physiological learning,” Institute of Science and Technology Austria, 2023.' ista: 'Alcarva C. 2023. Plasticity in the cerebellum: What molecular mechanisms are behind physiological learning. Institute of Science and Technology Austria.' mla: 'Alcarva, Catarina. Plasticity in the Cerebellum: What Molecular Mechanisms Are behind Physiological Learning. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:12809.' short: 'C. Alcarva, Plasticity in the Cerebellum: What Molecular Mechanisms Are behind Physiological Learning, Institute of Science and Technology Austria, 2023.' date_created: 2023-04-06T07:54:09Z date_published: 2023-04-06T00:00:00Z date_updated: 2023-04-26T12:16:56Z day: '06' ddc: - '570' degree_awarded: PhD department: - _id: GradSch - _id: RySh doi: 10.15479/at:ista:12809 file: - access_level: closed checksum: 35b5997d2b0acb461f9d33d073da0df5 content_type: application/pdf creator: cchlebak date_created: 2023-04-07T06:16:06Z date_updated: 2023-04-07T06:16:06Z embargo: 2024-04-07 embargo_to: open_access file_id: '12814' file_name: Thesis_CatarinaAlcarva_final pdfA.pdf file_size: 9881969 relation: main_file - access_level: closed checksum: 81198f63c294890f6d58e8b29782efdc content_type: application/pdf creator: cchlebak date_created: 2023-04-07T06:17:11Z date_updated: 2023-04-07T06:17:11Z file_id: '12815' file_name: Thesis_CatarinaAlcarva_final_for printing.pdf file_size: 44201583 relation: source_file - access_level: closed checksum: 0317bf7f457bb585f99d453ffa69eb53 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: cchlebak date_created: 2023-04-07T06:18:05Z date_updated: 2023-04-07T06:18:05Z file_id: '12816' file_name: Thesis_CatarinaAlcarva_final.docx file_size: 84731244 relation: source_file file_date_updated: 2023-04-07T06:18:05Z has_accepted_license: '1' language: - iso: eng month: '04' oa_version: Published Version page: '115' project: - _id: 267DFB90-B435-11E9-9278-68D0E5697425 name: 'Plasticity in the cerebellum: Which molecular mechanisms are behind physiological learning?' publication_identifier: issn: - 2663 - 337X publication_status: published publisher: Institute of Science and Technology Austria status: public supervisor: - first_name: Ryuichi full_name: Shigemoto, Ryuichi id: 499F3ABC-F248-11E8-B48F-1D18A9856A87 last_name: Shigemoto orcid: 0000-0001-8761-9444 title: 'Plasticity in the cerebellum: What molecular mechanisms are behind physiological learning' type: dissertation user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9 year: '2023' ...