The lab of Prof. Judkewitz focuses on understanding how large populations of neurons work together across the brain to enable behavior. This is particularly challenging in vertebrates because of the size and opacity of their tissues. To address this, the project employs two complementary strategies: developing advanced optical imaging techniques and using Danionella, a transparent fish with the smallest known vertebrate brain, as a model organism.
Optical imaging is a central component of the project. Biological tissues are often opaque due to light scattering, which limits the depth of imaging. The project involves pioneering new approaches in wavefront shaping, multiphoton microscopy, and optical time reversal to overcome these limitations, allowing for deeper tissue imaging that was previously unattainable. These advances hold significant promise for broad biomedical applications, such as improving disease diagnostics and understanding deep-brain circuits in vertebrates.
In parallel, the lab focuses on developing Danionella as a new vertebrate model for neuroscience research. This species has a tiny, transparent brain, making it ideal for whole-brain imaging. Despite its small size, Danionella displays complex behaviors, including acoustic communication. The project has implemented transgenesis, genome sequencing, and CRISPR/Cas9 genome editing in Danionella, providing unique opportunities to investigate the neural circuits underlying behavior at single-cell
resolution.
Several significant results have emerged from work supported by the Foundation. A study published in Nature revealed how fish are able to localize sound in water, where traditional mechanisms such as interaural time and level differences are less effective due to the properties of the aquatic environment. Another study, published in PNAS, explored how Danionella produces extremely loud sounds despite its small size, using ultrafast video and molecular analyses to uncover the mechanisms behind this phenomenon. Additionally, a study in the Journal of Experimental Biology examined the developmental timeline of sound production in Danionella, shedding light on how this ability emergesearly in life.
Furthermore, the project has developed an advanced method for high-speed three-dimensional scanning. This method allows for the measurement of neuronal activity with unprecedented speed and resolution, facilitating detailed investigations of brain-wide neural activity in real-time. These findings represent important steps forward in the understanding of vertebrate neural circuits and behavior, and highlight the contributions of this project to both technological innovation and biological discovery.