previous arrow
next arrow

Research : Why do we sleep? What are dreams?

Sleep in mammals has evolved into a complex phenomenon composed of two distinct states, REM (rapid eye movement) sleep and non-REM sleep. REM sleep is the major source of dreams, whereas non-REM sleep is characterized by a synchronous brain activity called slow waves. Little is known, however, about the evolutionary origin or individual roles of these two sleep states. We will address these questions through identification and manipulation of the neurons that function as the REM/non-REM sleep switch using mice.

While REM and non-REM sleep are unique to certain vertebrate species, sleep itself is a widely conserved phenomenon. The nematode Caenorhabditis elegans, with its genetic accessibility and well-defined neural circuit, is a powerful means for neuroscience research. Therefore, our lab also aims to elucidate widely conserved molecular mechanisms underlying sleep using C. elegans.

Joining our Lab

Our lab is interested in the evolution and function of sleep. Currently, our lab has two major themes: 1. elucidation of the individual roles and evolutionary origins of REM and non-REM sleep using mice, and 2. identification of widely conserved molecular mechanisms underlying sleep using the nematode C. elegans. To this end, we will combine pharmacogenetic or optogenetic approaches with behavioral studies, neuronal recording studies, or imaging studies. Lab members are expected to be either familiar with these techniques or highly motivated to acquire them. In addition, to gain a broad insight, we expect that all lab members be engaged in both the mouse and nematode projects.


2022.09.06 Awards


Mr. Shinnosuke Yasugaki (4th year medical student at the University of Tsukuba) received “The Best Presentation Award, Wakate Dojo” at the Conference of NEURO2022. The presentation title is “Does artificially increased REM sleep affect stress resilience in mice?”.

2022.06.20 Achievement


Mr. Shinichi Miyazaki, (4th year student, Ph.D. Program in Humanics, University of Tsukuba), published a first author paper in iScience (Cell Press). Title: Intracellular Ca 2+ dynamics in the ALA neuron reflect sleep pressure and regulate sleep in Caenorhabditis elegans [Message from Mr. …

2022.05.18 Achievement


Ms. Hibiki Okamura (2nd year student, Ph.D. Program in Humanics, University of Tsukuba) published a first author paper in eNeuro. Title: Long-Term Effects of Repeated Social Defeat Stress on Brain Activity during Social Interaction in BALB/c MicePublished online April 18, …