Statistical Analysis of Zebrafish Locomotor Response

Abstract

Zebrafish larvae display rich locomotor behaviour upon external stimulation. The movement can be simultaneously tracked from many larvae arranged in multi-well plates. The resulting time-series locomotor data have been used to reveal new insights into neurobiology and pharmacology. However, the data are of large scale, and the corresponding locomotor behavior is affected by multiple factors. These issues pose a statistical challenge for comparing larval activities. To address this gap, this study has analyzed a visually-driven locomotor behaviour named the visual motor response (VMR) by the Hotelling’s T-squared test. This test is congruent with comparing locomotor profiles from a time period. Different wild-type (WT) strains were compared using the test, which shows that they responded differently to light change at different developmental stages. The performance of this test was evaluated by a power analysis, which shows that the test was sensitive for detecting differences between experimental groups with sample numbers that were commonly used in various studies. In addition, this study investigated the effects of various factors that might affect the VMR by multivariate analysis of variance (MANOVA). The results indicate that the larval activity was generally affected by stage, light stimulus, their interaction, and location in the plate. Nonetheless, different factors affected larval activity differently over time, as indicated by a dynamical analysis of the activity at each second. Intriguingly, this analysis also shows that biological and technical repeats had negligible effect on larval activity. This finding is consistent with that from the Hotelling’s T-squared test, and suggests that experimental repeats can be combined to enhance statistical power. Together, these investigations have established a statistical framework for analyzing VMR data, a framework that should be generally applicable to other locomotor data with similar structure.

From behavior to circuit modeling of light-seeking navigation in zebrafish larvae

“…However, one should be aware that such observation is only valid provided that the sensory context remains relatively stable. Hence for instance, a prolonged uniform drop in luminosity is known to enhance the overall motor activity (generally measured by displacement over a period of time) for up to several tens of minutes ( Prober et al, 2006 ; Emran et al, 2007 , 2009 ; Liu et al, 2015) . This long-term behavioral change, so-called photokinesis, might be regulated by deep brain photoreceptors ( Fernandes et al, 2013 ; Horstick et al, 2017) and thus constitutes a distinct mechanism.…”

Hypo- or hyperactivity of zebrafish embryos provoked by neuroactive substances: a review on how experimental parameters impact the predictability of behavior changes

“…They concluded that the strain might influence locomotor activity of zebrafish. Similarly, Liu et al [73] reported behavioral differences of strains (TL, TLAB and AB) when measuring locomotion during abrupt changes in light cycles. Strain differences were also found in a study on survival and neurocranial effects of ethanol [75].…”

Hcfc1a regulates neural precursor proliferation and asxl1 expression in the developing brain.

“…Zebrafish have emerged as a model for neurodevelopmental disorders (59) and behavioral assays for seizure (60) and motor deficits (61) have been described. Therefore, we characterized the locomotion of hcfc1a mutants in response to light stimulus (62). Our results using Zebrabox technology demonstrated reduced motility as indicated by distance travelled without defects in overall speed.…”