Bahl Lab

Congratulations to Susanne (mentored by post-doc @mehaj.bsky.social) for successfully defending her master's thesis investigating neural dynamics in the larval zebrafish brain 🥳 Wishing you the best of luck with your #jobsearch for a PhD position!

This work would not have been possible without the support of @uni-konstanz.de‬, @cbehav.bsky.social, @mpi-animalbehav.bsky.social, @zukunftskolleg.bsky.social, @erc.europa.eu‬, @boehringerglobal.bsky.social, NIH U19, and @dfg.de‬. (7/7)

A big thanks to our co-authors Sophie Aimon, @maxcapelle.bsky.social‬, @flofightscience.bsky.social‬, Heike Naumann, Herwig Baier, Krasimir Slanchev, as well as our colleagues in the Neurobiology department, and scientific support structures of the @uni-konstanz.de. (6/7)

These results demonstrate how distinct visual features are extracted, processed in parallel, and eventually integrated to guide behavior. This modular and parallel circuit architecture provides a context-flexible solution for transforming sensory input into action. (5/7)

We investigated the morphology and neurotransmitters of functionally identified neurons and show how the identified pathways converge in the anterior hindbrain. (4/7)

Through brain-wide 2P calcium imaging, we identify neurons whose activity matches our model components. (3/7)

We find that zebrafish compute three visual features–motion, luminance level, and changes in luminance–and simply add cues to choose swim direction. Our model captures behavior and predicts potential computations in the brain. (2/7)

Larval zebrafish follow the direction of whole-field motion #OMR and prefer to swim towards brighter areas #phototaxis. But what happens in the brain when motion goes left, and there is brightness on the right? (1/7)

How do brains make decisions when faced with multiple, potentially conflicting cues? In our latest preprint, we show how #zebrafish use an additive strategy and process multiple visual features through anatomically distinct parallel pathways tinyurl.com/mvkn8em9 Thread 👇

These results demonstrate how distinct visual features are extracted, processed in parallel, and eventually integrated to guide behavior. This modular and parallel circuit architecture provides a context-flexible solution for transforming sensory input into action. (5/7)

We investigated the morphology and neurotransmitters of functionally identified neurons and show how the identified pathways converge in the anterior hindbrain. (4/7)

Through brain-wide 2P calcium imaging, we identify neurons whose activity matches our model components. (3/7)

The Behavioural Neurobiology Summer School in Kosovo is back for the 2nd year and after just a few days we already made it onto live TV! For anyone who speaks Albanian, you can check out the full broadcast here: shorturl.at/kpUzp 🎙️

This work would not have been possible without the support of @uni-konstanz.de‬, @cbehav.bsky.social, @mpi-animalbehav.bsky.social, @zukunftskolleg.bsky.social, @erc.europa.eu‬, @boehringerglobal.bsky.social, and @dfg.de. (10/10)

We suggest that zebrafish phototaxis is regulated via parallel processing streams, which could be a universal implementation to change strategies depending on developmental stage, context, or internal state, making behavior flexible and goal-oriented. (9/10)

Model-based extraction of latent cognitive variables points towards potential neural correlates of the observed behavioral inversion and illustrates a novel way to explore the mechanisms of vertebrate ontogeny. (8/10)

We ran simulations with virtual fish to test the model’s prediction for brightness navigation. Our model is able to qualitatively reproduce the behavior of the real fish. (7/10)

Using these pathways, we build a library of agent-based models to predict animal behavior across stimulation conditions and in more complex environments. (6/10)

We identify three parallel pathways: averaging whole-field luminance levels (A), comparing the contrast of light levels across eyes (C), and computing eye-specific temporal derivatives (D). (5/10)

Next, we quantified the turning behavior using a lateral brightness stimulus that is locked to the position of the fish. (4/10)

To test behavioral responses to whole-field brightness levels, we created a virtual circular gradient in which the brightness of the arena depends on the position of the fish. (3/10)

We apply a combination of modeling and complementary phototaxis assays in virtual reality to dissect the algorithmic basis of this transition. (2/10)

Larval zebrafish spend more time in the light, whereas juvenile zebrafish tend to approach darker regions. (1/10)

We are proud to have @maxcapelle.bsky.social's paper out on bioRxiv! He found that phototactic behavior in #zebrafish switches during #ontogeny🐟🔆 Through elegant behavioral dissections, he identifies the navigational strategies related to this transition. www.biorxiv.org/content/10.1... Thread 👇

For the next few months, he will move next door to the @mpi-animalbehav.bsky.social to work on animal tracking software, but we are looking forward to having him back in the lab to start his master's thesis at the end of the year!

Meet Max, a life science master's student at @uni-konstanz.de who joined our lab last year to work on ablating luminance change detecting cells in the larval zebrafish brain using 2P microscopy. His excellent work contributed to efforts in the lab to probe neural circuits underlying decision-making.

9A Spezial: Exzellent gefragt - How the Brain decides 9B · Episode

Curious how we study decision-making in the brain? PhD student Max Capelle talks about our research and methods in the @uni-konstanz.de student council podcast (in German): shorturl.at/4W6uF 🎙️

Check it out to learn more about how we combine 2P microscopy, behavioral experiments, and data analysis.

Sledding from the Bahl lab retreat into #NWG2025! Come check out our posters and talks over the next few days. See you there!

Such biophysically realistic network modeling provides the foundation for precise hypothesis-driven circuit manipulations, electrophysiology, and transcriptomic analysis in the future. So stay tuned😄(10/10)

Our anterior hindbrain circuit model, based on ground-truth connectivity, reproduces experimentally observed neural dynamics and predicts new mechanisms for flexible decision-making. (9/10)