INFORMATION PROCESSING BY GLOBAL REMODELED NETWORKS

M.S. AUSAS, L MAZITELLI-FUENTES, AND L.A. MONGIAT

Ciudad Autónoma de Buenos Aires

Simposio; ?Simposio Fronteras en Biociencia 2?; 2016

Instituto de Investigación en Bomedicina de Buenos Aires - CONICET- Instituto Partner de la Sociedad Max Planck

Teleosts exhibit adult neurogenesis throughout their brain, making them an excellentmodel to study network remodeling. However, this study involves complex relationshipsbetween newly-added neurons and preexisting networks requiring to approach twoaspects of the problem: a) how new neurons alter activity in elder circuits, and b) hownetwork activity shapes the integration of new neurons into the circuit. Our research isfocused on studying the relationship between neuronal network remodeling and cognitivefunction. We demonstrate that the rainbow trout dorso-medial telencephalic region (Dm), issubjected to global network remodeling by adult neurogenesis. Interestingly Dmparticipates on information processing during an active avoidance (AA) associativelearning, as quantified by the expression levels of the immediate early gene c-fos, showingan increase higher than 1000% as compared to non learner controls. Moreover, the rate ofadult neurogenesis in trout telencephalon is prone to be modulated by physiologicalconditions, as four weeks of social restriction (SR) induces a 43% reduction on adultneurogenesis specifically on Dm. Further experiments will be conducted in order toexperimentally modulate Dm adult neurogenesis by SR, to evaluate in which way networkremodeling impinges on information processing and cognitive function. Cognitive functionwill be assayed as learning and memory performance on AA, information processing willbe evaluated by electrophysiology and calcium imaging on telencephalic slices, whereasadult neurogenesis and immediate early gene expression (as a measure of networkactivity) will be assayed on fixed tissue. Our data will be relevant to understand the rulesgoverning a proper neuronal addition to adult brain networks, with further implications forregenerative therapies.