An essential function of the central nervous system is to initiate animal’s behavior in response to dynamic changesin the environment. A complete understanding of this process requires acomprehensive analysis of the local and long-range neural circuits involved in specific behaviors.Our current research focuses on the neural circuits modulating the sleep-wake behavior.

　　Sleep-wake cycle is a universal phenomenon observed throughout mammals. Mutiple brain regions, including the hypothalamus, have been shown to play critical roles in the sleep-wake cycle. However, the exact underlying mechanism is not entirely clear.

　　Recent technical advances in the study of mouse behaviors provide an invaluable opportunity to address this question at multiple levels, including in vivo optrode recording or calcium imaging of the natural firing patterns of different neuronal types during sleep-wake cycle, optogenetic or pharmacogenetic manipulations ofthe activity of each cell type, and mapping the local and long-range synaptic connectivity using slice recording or virus-mediated tracing. Such strategy has been successfully applied to the analysis of basal forebrain circuits controlling the sleep-wake behavior (Xu, et. al. 2015). We will apply the same strategy to study the role of hypothalamus neuronal circuits on the modulation of the sleep-wake cycle. The ultimate goal of this study is to help us to understand a fundamental question in the sleep research: What makes us sleep?

　　Another direction of the lab is to explore the neural circuits involved in the top-down modulation of visual attention behavior (Zhang, et. al. 2014). This project represents a collaboration with Dr. Siyu Zhang of Shanghai Jiao Tong University.