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Stability, precision, and near-24-hour period of the human circadian pacemaker.
Estimation of the periods of the endogenous circadian rhythms of melatonin, core body temperature, and cortisol in healthy young and older individuals living in carefully controlled lighting conditions has revealed that the intrinsic period of the human circadian pacemaker averages 24.18 hours in both age groups, with a tight distribution consistent with other species. Expand
Sensitivity of the human circadian pacemaker to nocturnal light: melatonin phase resetting and suppression
It is demonstrated that humans are highly responsive to the phase‐delaying effects of light during the early biological night and that both the phase resetting response to light and the acute suppressive effect of light on plasma melatonin follow a logistic dose‐response curve, as do many circadian responses to light in mammals. Expand
The Critical Care Safety Study: The incidence and nature of adverse events and serious medical errors in intensive care*
Adverse events and serious errors involving critically ill patients were common and often potentially life-threatening, and failure to carry out intended treatment correctly was the leading category. Expand
Measuring and using light in the melanopsin age
A new light-measurement strategy taking account of the complex photoreceptive inputs to these non-visual responses is proposed for use by researchers, and simple suggestions for artificial/architectural lighting are provided for regulatory authorities, lighting manufacturers, designers, and engineers. Expand
Short-wavelength sensitivity for the direct effects of light on alertness, vigilance, and the waking electroencephalogram in humans.
The frequency-specific changes in the waking EEG indicate that short-wavelength light is a powerful agent that immediately attenuates the negative effects of both homeostatic sleep pressure and the circadian drive for sleep on alertness, performance, and the ability to sustain attention. Expand
A Phase Response Curve to Single Bright Light Pulses in Human Subjects
These data provide a comprehensive characterization of the human phase response curves (PRCs) to single bright light exposures under highly controlled laboratory conditions. Expand
Dose-response relationship for light intensity and ocular and electroencephalographic correlates of human alertness
Light can elicit both circadian and acute physiological responses in humans. In a dose response protocol men and women were exposed to illuminances ranging from 3 to 9100 lux for 6.5 h during theExpand
Effect of reducing interns' work hours on serious medical errors in intensive care units.
Eliminating extended work shifts and reducing the number of hours interns work per week can reduce serious medical errors in the intensive care unit. Expand
High sensitivity of the human circadian melatonin rhythm to resetting by short wavelength light.
It is reported here that the circadian resetting response in humans, as measured by the pineal melatonin rhythm, is also wavelength dependent, and photopic lux, the standard unit of illuminance, is inappropriate when quantifying the photic drive required to reset the human circadian pacemaker. Expand
Dynamics of electroencephalographic sleep spindles and slow wave activity in men: effect of sleep deprivation
These data demonstrate that when averaged per sleep episode or non-REM sleep episode an inverse relationship between SWA and spindle activity exists but that in the initial and final part of non-Rapid-eye-movement sleep episodes the association between these two activities is positive. Expand