Ethanol modifies zebrafish responses to abrupt changes in light intensity

Zebrafish exhibit a preference for dark areas and this behavior has been used to characterize anxiety. Their responses to light may also be modified by ethanol. Using high-speed video recordings, we demonstrated that untreated animals were relatively more active immediately after a bright-dim transition compared to animals exposed to low dose ethanol (2%). Additionally, ethanol-treated larvae were more prone to initiating behavioral responses following abrupt changes of light intensity. In conclusion, the larval zebrafish is an excellent model for investigating locomotory kinetics as well as drugs with anxiolytic properties. High-speed video recordings of behavioral responses in this species are indeed very promising for high-throughput screening.