Development of the nocturnal sleep electroencephalogram in human infants

The development of nocturnal sleep and the sleep electroencephalogram (EEG) was investigated in a longitudinal study during infancy. All-night polysomnographic recordings were obtained at home at 2 wk and at 2, 4, 6, and 9 mo after birth (analysis of 7 infants). Total sleep time and the percentage of quiet sleep or non-rapid eye movement sleep (QS/NREMS) increased with age, whereas the percentage of active sleep or rapid eye movement sleep (AS/REMS) decreased. Spectral power of the sleep EEG was higher in QS/NREMS than in AS/REMS over a large part of the 0.75- to 25-Hz frequency range. In both QS/NREMS and AS/REMS, EEG power increased with age in the frequency range <10 Hz and >17 Hz. The largest rise occurred between 2 and 6 mo. A salient feature of the QS/NREMS spectrum was the emergence of a peak in the sigma band (12-14 Hz) at 2 mo that corresponded to the appearance of sleep spindles. Between 2 and 9 mo, low-frequency delta activity (0.75-1.75 Hz) showed an alternating pattern with a high level occurring in every other QS/NREMS episode. At 6 mo, sigma activity showed a similar pattern. In contrast, theta activity (6.5-9 Hz) exhibited a monotonic decline over consecutive QS/NREMS episodes, a trend that at 9 mo could be closely approximated by an exponential function. The results suggest that 1) EEG markers of sleep homeostasis appear in the first postnatal months, and 2) sleep homeostasis goes through a period of maturation. Theta activity and not delta activity seems to reflect the dissipation of sleep propensity during infancy.

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Normal EEG in Wakefulness and Sleep

10.1093/med/9780190228484.003.0008 ◽

2017 ◽

Cited By ~ 1

Author(s):

Vaishnav Krishnan ◽

Bernard S. Chang ◽

Donald L. Schomer

Keyword(s):

Eye Movement ◽

Low Voltage ◽

Theta Activity ◽

Normal Adult ◽

Alpha Band ◽

Rapid Eye Movement ◽

Rapid Eye Movement Sleep ◽

Delta Activity ◽

Electroencephalogram Eeg

The normal adult electroencephalogram (EEG) is not a singular entity, and recognizing and appreciating the various expressions of a normal EEG is vital for any electroencephalographer. During wakefulness, the posterior dominant rhythm (PDR) must display a frequency within the alpha band, although an absent PDR is not abnormal. A symmetrically slowed PDR, excessive theta activity, or any delta activity during wakefulness is abnormal and a biomarker of encephalopathy. Low-voltage EEGs have been associated with a variety of neuropathological states but are themselves not abnormal. During non-rapid eye movement sleep, a normal EEG will display progressively greater degrees of background slowing and amplitude enhancement, which may or may not be associated with specific sleep-related transients. In contrast, the EEG during rapid eye movement sleep more closely resembles a waking EEG (“desynchronized”) in amplitude and background frequencies. Across both wakefulness and sleep, significant asymmetries in background frequencies and amplitude are abnormal.

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The European starling (Sturnus vulgaris) shows signs of NREM sleep homeostasis but has very little REM sleep and no REM sleep homeostasis

SLEEP ◽

10.1093/sleep/zsz311 ◽

2019 ◽

Vol 43 (6) ◽

Cited By ~ 4

Author(s):

Sjoerd J van Hasselt ◽

Maria Rusche ◽

Alexei L Vyssotski ◽

Simon Verhulst ◽

Niels C Rattenborg ◽

...

Keyword(s):

Sleep Deprivation ◽

Eye Movement ◽

Rem Sleep ◽

Spectral Power ◽

Nrem Sleep ◽

Sleep Time ◽

European Starling ◽

Dark Phase ◽

Rapid Eye Movement ◽

Sleep Homeostasis

Abstract Most of our knowledge about the regulation and function of sleep is based on studies in a restricted number of mammalian species, particularly nocturnal rodents. Hence, there is still much to learn from comparative studies in other species. Birds are interesting because they appear to share key aspects of sleep with mammals, including the presence of two different forms of sleep, i.e. non-rapid eye movement (NREM) and rapid eye movement (REM) sleep. We examined sleep architecture and sleep homeostasis in the European starling, using miniature dataloggers for electroencephalogram (EEG) recordings. Under controlled laboratory conditions with a 12:12 h light–dark cycle, the birds displayed a pronounced daily rhythm in sleep and wakefulness with most sleep occurring during the dark phase. Sleep mainly consisted of NREM sleep. In fact, the amount of REM sleep added up to only 1~2% of total sleep time. Animals were subjected to 4 or 8 h sleep deprivation to assess sleep homeostatic responses. Sleep deprivation induced changes in subsequent NREM sleep EEG spectral qualities for several hours, with increased spectral power from 1.17 Hz up to at least 25 Hz. In contrast, power below 1.17 Hz was decreased after sleep deprivation. Sleep deprivation also resulted in a small compensatory increase in NREM sleep time the next day. Changes in EEG spectral power and sleep time were largely similar after 4 and 8 h sleep deprivation. REM sleep was not noticeably compensated after sleep deprivation. In conclusion, starlings display signs of NREM sleep homeostasis but the results do not support the notion of important REM sleep functions.

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Basolateral amygdala regulates EEG theta-activity during rapid eye movement sleep

Neuroscience ◽

10.1016/j.neuroscience.2021.06.018 ◽

2021 ◽

Author(s):

Mayumi Machida ◽

Brook L.W. Sweeten ◽

Austin M. Adkins ◽

Laurie L. Wellman ◽

Larry D. Sanford

Keyword(s):

Eye Movement ◽

Basolateral Amygdala ◽

Theta Activity ◽

Rapid Eye Movement ◽

Rapid Eye Movement Sleep

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Change of delta activity during rapid eye movement sleep in patients with brain tumor

Electroencephalography and Clinical Neurophysiology ◽

10.1016/0013-4694(73)90042-4 ◽

1973 ◽

Vol 34 (2) ◽

pp. 153-162 ◽

Cited By ~ 6

Author(s):

Shoichiro Ohgami

Keyword(s):

Brain Tumor ◽

Eye Movement ◽

Rapid Eye Movement ◽

Rapid Eye Movement Sleep ◽

Delta Activity

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Effect of elevated ambient temperature on sleep, EEG spectra, and brain temperature in the rat

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1995.268.6.r1365 ◽

1995 ◽

Vol 268 (6) ◽

pp. R1365-R1373 ◽

Cited By ~ 6

Author(s):

B. O. Gao ◽

P. Franken ◽

I. Tobler ◽

A. A. Borbely

Keyword(s):

Ambient Temperature ◽

Eye Movement ◽

Spectral Power ◽

Dark Period ◽

Brain Temperature ◽

Spectral Power Density ◽

State Transitions ◽

Rapid Eye Movement ◽

Rapid Eye Movement Sleep ◽

Hypothalamic Temperature

To examine the relationship between sleep and brain temperature in the rat, the vigilance states, spectral power density of the electroencephalogram (EEG), hypothalamic temperature (T(hy)), and cortical temperature (Tcr) were recorded for 3 days. A 1-day rise of ambient temperature from 23 to 30 degrees C did not affect the percentage of waking, non-rapid eye movement sleep (NREMS), and rapid eye movement sleep (REMS), but increased EEG slow-wave activity in NREMS in the 12-h dark period. T(hy) was invariably higher than Tcr, but at 30 degrees C the difference diminished because of a rise in Tcr. In contrast to Tcr, T(hy) was only slightly increased at 30 degrees C and only during sleep and in the dark period. Although the temperatures changed largely in parallel at vigilance state transitions, Tcr rose more rapidly than T(hy) at NREMS-REMS transitions and more slowly at NREMS-waking transitions. T(hy) declined more rapidly than Tcr at waking-NREMS transitions and more slowly at REMS-NREMS transitions. The results are consistent with a central role of the hypothalamus in the activation and deactivation of the waking state.

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