FISH-VR · An immersive, versatile fish VR for studying whole-brain circuits during naturalistic experience of complex and flexible behaviours in the adult vertebrate

Animals navigate through complex, ever-changing environments, and can adapt to dramatic variations in their sensory inputs, internal states, and the effects of their motor outputs across different contexts. Despite the complexity of the natural environments in which brains evolved, most experiments in neuroscience use simple, artificial stimuli that are designed to evoke specific types of behaviour and neural activity, but are a poor facsimile of reality. Furthermore, most neural recording studies focus on single or few brain regions, and thus ignore the importance of interactions across the brain, especially during complex behaviours. Such hampered experimental approaches have been proven unsuccessful to reveal how diverse cell types across the nervous system interact to produce adaptive behaviour in complex, naturalistic environments. Here, I propose to address these challenges, to contribute to an improved understanding of how the brain works flexibly at large scale, when tackling a sensorimotor task. I will take advantage of the new animal model I established as a PhD student (the small, transparent micro glassfish Danionella cerebrum (DC)), and the techniques I learned and established as a postdoctoral fellow (whole-brain cellular-level calcium imaging, and a virtual reality arena system that allows to reversibly head-tether fish). I propose to conduct brain-wide calcium imaging from tethered adult Danionella as they gauge their behaviour during naturalistic closed-loop and partial open-loop controlled exploration in a complex and immersive virtual environment. My unique expertise will be essential to determine the cellular and network correlates of motor adaptation in an adult vertebrate, to advance our fundamental insight on the neurobiology of behaviour selection, and to establish a research program for exploring brain circuits for experience-dependent behaviours and context-dependent adaptation in the future.