Investigating Heading Representation in the Zebrafish Interpeduncular
Nucleus (2024 FENS-Kavli Network of Excellence PhD Thesis Prize)
Abstract
The brain’s ability to integrate sensory and motor information allows us
to maintain a sense of orientation in space, a process in which
head-direction cells play a key role. While these neurons have been
studied extensively in mammals, their presence and function in
non-mammalian species remain less understood. Here, I summarise the
research work for my PhD thesis, where we explore the interpeduncular
nucleus (IPN) in zebrafish, a lesser-known brain region, using
whole-brain electron microscopy and calcium imaging techniques. We
identified a novel population of unipolar neurons, with their activity
exhibiting a dynamic, rotational pattern during head movements, even in
the absence of sensory cues. This population mirrors the functionality
of head-direction cells observed in mammals, suggesting a conserved
mechanism for spatial orientation across vertebrates. Our findings
reveal the potential of the zebrafish IPN as a vertebrate model for
studying ring attractor networks, a theoretical framework previously
used to explain head-direction cell activity. These results pave the way
for future research on how motor and sensory signals converge in the
vertebrate brain to maintain spatial orientation.