Lily Yan, MD, PhD
Assistant Professor, Psychology
M.D., Ph.D., 2000, Kobe University School of Medicine, Japan
Location208 Giltner Hall
Circadian rhythms are generated by an internal time-keeping system that controls circadian activities ranging from gene transcription, cell division, and hormone secretion to sleep/wake cycle. In mammals, the master circadian clock is located in the suprachiasmatic nucleus (SCN) of the hypothalamus. The SCN clock is reset daily by the environmental light-dark schedule and this resetting process keeps the internal clock in synchrony with the environment. The temporal information generated in the SCN is sent to other brain regions and then further conveyed to peripheral tissues and organs. This hierarchical system functions to ensure that behavioral and physiological activities occur at optimal times. Any disturbance along the input to the out pathway leads to abnormal circadian function, which has been related to sleep, metabolic, psychological and neurodegenerative disorders.
My work focuses on three questions: 1), what is the neural mechanism underlying photic entrainment of the circadian clock? 2), how the cell oscillators in the SCN are organized to produce coherent circadian oscillation? 3), what is the nature of the SCN outputs controlling behavior and physiology?