Spontaneous Vigilance Fluctuations in the Daytime

摘要: Spontaneous fluctuations of vigilance during the daytime were studied in 412 electroencephalographic (EEG) records from 9 subjects. The EEGs recorded repeatedly 19–25 times between 0800 and 1900 each subject. Except 5-min recording periods when seated subjects examined with their eyes closed, encouraged to engage normal activities, such as reading knitting. changes level indicated by EEG measures based on automatic analysis. Statistical analyses data showed that occurred rhythmically a period 60 110 min. ultradian rhythms detectable even though engaged activity. Individual patterns were, however, observed be relatively unstable within-subjects comparisons made experiments conducted one six weeks apart.