Sleep deprivation is associated with slower EEG resting state gamma activity.

We spend approximately one-third of our lives asleep. This behavioral state plays a pivotal role in protecting physical and mental health. A lack of sleep has negative consequences on the brain and behavior. Electrophysiological studies have shown that gamma oscillations are involved in sleep-wake processes. However, gamma peak frequency and power characteristics remain unclear during a night of sleep deprivation. Forty-four (44) healthy young adults were enrolled in this EEG study. Participants were randomly assigned to a rested control group (RC: n = 22, 13 female) or a night of sleep deprivation group (SD; n = 22, 12 female). The SD group was required to stay awake 24 h before the morning EEG session, whereas the RC group maintained their 7-9 h of habitual night sleep before the session. Sleepiness evaluations were conducted before the EEG for both groups. Eight minutes of resting-state EEG were recorded for all participants (4 min. eyes-open, 4 min. eyes-closed). Peak frequency (Hz) and power (μV2) values for gamma frequency band (28-48 Hz) were investigated. Our results revealed that one night of SD group rated their sleepiness significantly higher than the RCs. In EEG results, gamma peak frequency of the SD group in the eyes-open condition was significantly lower than that of the RCs. In contrast, power values were not different between groups. In light of our findings, the neural mechanisms of gamma oscillations and their potential links to sleep deprivation are discussed.