Author's email address D.-J. Dijk: firstname.lastname@example.org
Variation of electroencephalographic activity during non-rapid eye movement and rapid eye movement sleep with phase of circadian melatonin rhythm in humans
Article first published online: 29 SEP 2004
The Journal of Physiology
Volume 505, Issue 3, pages 851–858, December 1997
How to Cite
Dijk, D.-J., Shanahan, T. L., Duffy, J. F., Ronda, J. M. and Czeisler, C. A. (1997), Variation of electroencephalographic activity during non-rapid eye movement and rapid eye movement sleep with phase of circadian melatonin rhythm in humans. The Journal of Physiology, 505: 851–858. doi: 10.1111/j.1469-7793.1997.851ba.x
- Issue published online: 29 SEP 2004
- Article first published online: 29 SEP 2004
- Received 19 February 1997; accepted 12 September 1997.
- 1The circadian pacemaker regulates the timing, structure and consolidation of human sleep. The extent to which this pacemaker affects electroencephalographic (EEG) activity during sleep remains unclear.
- 2To investigate this, a total of 1.22 million power spectra were computed from EEGs recorded in seven men (total, 146 sleep episodes; 9 h 20 min each) who participated in a one-month-long protocol in which the sleep–wake cycle was desynchronized from the rhythm of plasma melatonin, which is driven by the circadian pacemaker.
- 3In rapid eye movement (REM) sleep a small circadian variation in EEG activity was observed. The nadir of the circadian rhythm of α-activity (8.25–10.5 Hz) coincided with the end of the interval during which plasma melatonin values were high, i.e. close to the crest of the REM sleep rhythm.
- 4In non-REM sleep, variation in EEG activity between 0.25 and 11.5Hz was primarily dependent on prior sleep time and only slightly affected by circadian phase, such that the lowest values coincided with the phase of melatonin secretion.
- 5In the frequency range of sleep spindles, high-amplitude circadian rhythms with opposite phase positions relative to the melatonin rhythm were observed. Low-frequency sleep spindle activity (12.25–13.0 Hz) reached its crest and high-frequency sleep spindle activity (14.25–15.5Hz) reached its nadir when sleep coincided with the phase of melatonin secretion.
- 6These data indicate that the circadian pacemaker induces changes in EEG activity during REM and non-REM sleep. The changes in non-REM sleep EEG spectra are dissimilar from the spectral changes induced by sleep deprivation and exhibit a close temporal association with the melatonin rhythm and the endogenous circadian phase of sleep consolidation.