Serotonin, learning, stress resilience and psychedelics

Serotonin in the brain governs many aspects of animal and human behaviors, including learning and mood control. Yet, we know little about how the serotonin system operates during various contexts, partly because the serotonin system is embedded in the deepest part of our brain. Thus, we take advantage of the zebrafish's transparent brain to study the working principles of the serotonin system and how we can engineer this system. We discovered that the serotonin system governs motor learning in zebrafish (2016) by performing real-time sensory error computations (2025) using optical imaging methods, including whole-brain neural activity imaging and voltage imaging. We also clarified how it governs brain-wide sensorimotor computation during learning (2024). We are currently expanding the scope of serotonin research to broader behavioral contexts, such as threat sensation and nociception.

Recently, serotonergic psychedelics have reemerged as a promising class of antidepressants that can exert lasting improvements in mood-related disorders. We recently discovered that a magic mushroom substance, psilocybin, acutely enhances stress resilience while also exerting psychostimulatory effects (2024). We now investigate the neural mechanisms of such effects. Also, in collaboration with Yeda, G-INCPM and Palo Santo Investments, we are developing a platform for screening novel serotonergic compounds that can have similar stress resilience effects with fewer side effects. 

Related literature

1. Kawashima et al., 2025
   "Voltage imaging reveals circuit computations in the raphe underlying serotonin-mediated motor vigor learning"
   Neuron. (2025)
2. Braun*, Rosenberg* et al.,
   "High-resolution tracking of unconfined zebrafish behavior reveals stimulatory and anxiolytic effects of psilocybin"
   Molecular Psychiatry. (2024)
3. Kawashima
   "The role of the serotonergic system in motor control"
   Neuroscience Research. 129: 32-39 (2019)
4. Kawashima et al.
   "The Serotonergic System Tracks the Outcomes of Actions to Mediate Short-Term Motor Learning"
   Cell. 167:933-946 (2016)