Expérimental et théorique
In this internship, the student will carry out functional brain imaging on a small fish (Danionella cerebrum), whose small and transparent brain makes it amenable to whole-brain recording in vivo. The recording will take place as the partially tethered animal virtually explores its environment. Our primary objective is to identify, in this novel vertebrate model, populations of head-directions (HD) cells, i.e. neurons whose activity is controlled by the spatial orientation of the animal. These neurons have been found in many species and are central to spatial navigation as they act collectively as a neuronal compass. They are believed to function as a “ring attractor”, i.e. a dynamic system whose continuum of attractor configurations encodes the animal orientation. We will leverage the unique possibility offered by this animal to perform functional imaging throughout its development in order to explore how the HD cells circuit progressively acquires the specific properties of a ring attractor. We further aim to reveal how various sensory inputs, including visual, vestibular, and proprioceptive cues, converge to drive the dynamics of the HD circuit, ensuring the accurate representation of the animal's orientation. The internship will combine state-of-the art imaging techniques, close-loop virtual reality assays, as well as computational and analytical methods, inspired from statistical physics, to model neuronal circuits.