Dr. Kim Palacios-Flores "DYNAMIC COGNITIVE REPRESENTATIONS IN THE ADULT ZEBRAFISH TELENCEPHALON"

Speaker : Kim Palacios-Flores
Postdoctoral Researcher at Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland

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Title : DYNAMIC COGNITIVE REPRESENTATIONS IN THE ADULT ZEBRAFISH TELENCEPHALON

Abstruct : Cognition relies on internal models of the world that allow the brain to interpret sensory information and predict future events. Such models are thought to involve the representation of relevant information in cognitive maps. To explore whether cognitive maps exist in teleosts we performed in vivo two-photon calcium imaging of the dorsal telencephalon of head-fixed adult zebrafish behaving in a virtual reality. Fish performed linear traversals (trials) of a 3D virtual corridor with sets of complex landmarks either present or absent along the walls of the corridor. We found many neurons with spatially selective activity under the first condition, and significantly fewer under the second condition. In the presence of complex landmarks, individual neurons often had one or more firing fields that could be associated with such landmarks. Collectively, the firing fields of the neuronal population tiled the environment. Importantly, spatially modulated activity of individual neurons evolved over trials even under a constant environment. Moreover, the deletion of all landmarks for 5 consecutive trials (perturbation window) elicited a rich diversity of neural responses. These included both spatially selective activity as well as elevated activity with lower spatial selectivity, the latter being consistent with prediction errors. These data reveal access to a memory during the perturbation window and its comparison with the current altered state of the environment. Our results provide strong evidence for cognitive representations in the telencephalon of an adult teleost and highlight their dynamic nature.