Zebrafish Locomotion and Balance Research

A three-paper story of how my fascination with gravity sensation and balance in zebrafish evolved.

This project is the story of how I became fascinated by one question: how does a small fish stay stable, orient to gravity, and still move efficiently through a noisy world? Across three papers, that question grew from perception, to circuit pathology, to state-dependent motor strategy.

Chapter 1 (2022): Gravity and Social Motion

I started from perception. In this work, we tested whether zebrafish distinguish gravity-compatible biological motion from gravity-incompatible motion. Using shoaling behavior, we found that fish preferentially approached and oriented to upright biological motion compared with inverted or non-biological controls. That result suggested that gravity is not just a force fish compensate for mechanically, but also a cue embedded in how they interpret animate behavior.

Representative figure from the original PDF of "Gravity-Dependent Animacy Perception in Zebrafish" (Figure 4).

Chapter 2 (2024): When Balance Circuits Become Vulnerable

After asking how gravity cues are perceived, I shifted to how balance circuits fail. This study showed that tau load in specific brainstem populations predicts distinct balance phenotypes before overt cell death. Higher tau in vestibulospinal-associated regions was linked to worse postural stability, while relative load across vestibulospinal and INC/nMLF populations tracked changes in navigation consistency. It reframed balance deficits as circuit-specific and load-dependent, rather than a late, non-specific consequence of degeneration.

Representative figure from the original PDF of "Tau load in select brainstem neurons predicts the severity and nature of balance deficits in the absence of cell death" (Figure 3).

Chapter 3 (2025): Strategy Switching Across Light and Circadian States

The next step was understanding how healthy larvae dynamically balance stability and exploration over day-night contexts. We identified two locomotor modes: in darkness, fish used longer bouts with stronger compensatory nose-up rotations to offset accumulated nose-down drift; in light, they used shorter, more frequent bouts with greater directional variability for navigation. Light acted as the dominant driver, while circadian state modulated the magnitude of each strategy. For me, this connected the full arc: gravity-sensitive perception, gravity-relevant circuit pathology, and adaptive motor control under changing environmental conditions.

Representative figure from the original PDF of "Lighting and circadian cues shape locomotor strategies for balance and navigation in larval zebrafish" (Figure 3).

Together, these studies define my ongoing research direction: how gravity sensation and neural circuit dynamics shape stable yet flexible behavior. For full citations and downloadable manuscripts, see the publications page.