Somnowatch plus

Fifteen adults aged between 20 and 40 years participated in this study and maintained consistent sleep–wake patterns for at least 3 days preceding the MRI scan. Their wake-sleep rhythms were monitored through wrist actigraphy (SOMNOwatchTM plus, SOMNOmedics GmbH, Randersacker, Germany). All participants self-reported to have ability to undergo EEG-fMRI scanning without history of neurological, or psychiatric diseases. Neither alcohol nor caffeinated products were allowed on the scanning day. The Pittsburgh Sleep Quality Index (PSQI) was administered to all participants to assess their sleep quality and disturbances over a 1-month period. All study procedures were approved by the Research Ethics Committee of National Taiwan University (Approval No. 201512ES054). Informed consent was obtained from all participants included in the study.

Twenty-one healthy subjects (age: 26.6 ± 4.18, 10 females) participated in this study. All subjects reported no neurological and psychiatric disorders, and were given the Pittsburgh Sleep Quality Index (PSQI) to assess for any sleep disturbances over a one-month period before experimentation. Subjects were then asked to maintain a consistent sleep–wake schedule, monitored through wrist actigraphy (SOMNOwatchTM plus, SOMNOmedics GmbH, Randersacker, Germany), for more than three days prior to experiment. Through the actigraphy records, we could confirm that all participants maintained a consistent sleep–wake cycle, which enabled us to determine the habitual sleep time for each participant. All methods were performed in accordance with the relevant guidelines and regulations by the National Yang-Ming University University Institutional Review Board (YMeIRB, Approval No. 201512ES054). All participants provided written consent to the study procedures.