Methods to Study Sleep in Zebrafish

Sleep is a fundamental behavioral state that is observed throughout the animal kingdom, yet our understanding of this state remains limited. Zebrafish are a useful vertebrate animal model to dissect genetic and neuronal mechanisms underlying the regulation of sleep and wake states. The diurnal circadian pattern of sleep–wake cycles in zebrafish is similar to that of humans, and many sleep-regulating neuropeptides and hormones that are found in humans, such as melatonin and hypocretin, play similar roles in zebrafish. Due to their small size, rapid development, and optical transparency, larval zebrafish are well suited for high-throughput screens to identify genes, neurons, and drugs that regulate sleep. Numerous techniques and genetic tools have been established that enable powerful approaches to explore mechanisms that underlie zebrafish sleep. In this chapter, we will discuss current approaches to studying sleep in larval zebrafish, including detailed experimental procedures, and describe the advantages and limitations of each approach.