A population dynamics model about how learning promotes adult neurogenesis in delimited regions of the zebrafish pallium

CASTILLO ELÍAS, JULIO R; MONGIAT, LUCAS A

Congreso; XXXVI Annual Meeting of the Argentinian Society for Neuroscience Research; 2021

Sociedad Argentina de Neurociencias

Neural stem cells (NSCs) in the zebrafish pallium undergo through both symmetric and asymmetric divisions in order to generate new-born neurons and to perpetuate the NSC reservoir pool. A few studies address how the activity of neural circuits regulates the adult neurogenesis homeostasis, while the role of cognitive activity on new-born neuronal addition has not been explored yet. Here we aimed to test whether cognitive activity enhances adult neurogenesis by training zebrafish in a spatial relational task. We found that learning increases a ~3 fold NSC proliferation in the rostral-dorsomedial (rDm) pallium, when compared to mocked controls. Next we evaluated the role of learning on neuronal addition in the pallium. To do this, a cohort of proliferating NSCs were labeled by BrdU administration, and then fish were trained during 2 or 3 consecutive weeks. We found that training increases the number of newborn neurons in rDm proportional to the extent of cognitive activity. To understand the cellular mechanisms behind these results, we developed a population dynamic model of proliferating NSCs (based on Than-Trong el al 2020), where NSC proliferation and death are sensitive to cognitive activity. Our model suggests that learning in a spatial relational task promotes neurogenesis in rDm in two ways: firstly, by promoting newborn neurons’ rescue from apoptosis due to network activity, and secondly, by acting as a catalyst for a successive labeled-NSCs proliferation.