Auditory processing by distributed circuits in the new vertebrate model Danionella translucida

• Applicant: Professor Dr. Benjamin Judkewitz, Ph.D.
• Subject Area: Cognitive, Systems and Behavioural Neurobiology
• Term: from 2020 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 432195732

To ensure an animal’s survival, distributed networks of neurons perform intricate computations to detect and discern the nature of environmental stimuli. In order to study the neural basis of these computations we need to observe the activity of many neurons across multiple brain areas. Yet, methodological constraints have led to a focus on individual cells or small groups of neurons in isolated brain regions. Dense recordings of neuronal population activity across brain regions would not only uncover rare cell and response types that have been missed by single-cell recordings – they would also enable the study of population-level representations, topology, and inter-area interactions.The goal of the proposed project is to understand how acoustic information is transformed by neuronal populations across successive processing steps of the vertebrate auditory pathway. To achieve this goal we will take advantage of the unique properties of the transparent vocalizing fish Danionella translucida, allowing us for the first time to densely measure neuronal population activity across the entire auditory system of an adult vertebrate. We aim to map the auditory anatomy of Danionella using targeted application of neural tracers, tissue clearing and whole-brain imaging. This will then serve as basis for whole-brain functional two-photon imaging of sensory-evoked neuronal population activity across the auditory pathway. Finally, we will combine functional imaging with tracing in order to identify and monitor the activity of projection neurons and their downstream target brain areas.If successful, this study will establish Danionella as the first adult vertebrate model organism with full optical access to its entire auditory processing chain and it will provide important insights into structure and function of the vertebrate auditory pathway at the population level.

• DFG Programme: Research Grants