1 Department of Sleep Medicine, Shantou University Mental Health Center, Shantou University Medical College, Shantou 515041, China; Sleep Medicine Center, Shantou University Medical College, Shantou, China.
2 Sleep Research and Treatment Center, Department of Psychiatry, Penn State College of Medicine and Penn State Health Milton S Hershey Medical Center, Pennsylvania State University, Hershey, PA, USA.
3 Department of Sleep Medicine, Shantou University Mental Health Center, Shantou University Medical College, Shantou 515041, China; Sleep Medicine Center, Shantou University Medical College, Shantou, China. Electronic address: s_liyun@stu.edu.cn.