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Stability, precision, and near-24-hour period of the human circadian pacemaker.
Regulation of circadian period in humans was thought to differ from that of other species, with the period of the activity rhythm reported to range from 13 to 65 hours (median 25.2 hours) and theExpand
Factors inducing periodic breathing in humans: a general model.
A general model is developed to account for all kinds of periodic breathing (PB) resulting from instability in respiratory control: in normals during sleep and on acute exposure to high altitude, inExpand
Bright light induction of strong (type 0) resetting of the human circadian pacemaker.
The response of the human circadian pacemaker to light was measured in 45 resetting trials. Each trial consisted of an initial endogenous circadian phase assessment, a three-cycle stimulus whichExpand
Tree structures: deducing the principle of mechanical design.
Abstract A statistical description of the branching patterns of trees is proposed in the context of a power-law tapered beam model. Depending on the exponent which describes tapering of the depth ofExpand
Interactive Mathematical Models of Subjective Alertness and Cognitive Throughput in Humans
The authors present here mathematical models in which levels of subjective alertness and cognitive throughput are predicted by three components that interact with one another in a nonlinear manner.Expand
Quantifying Human Circadian Pacemaker Response to Brief, Extended, and Repeated Light Stimuli over the Phototopic Range
The authors' previous models have been able to describe accurately the effects of extended (5 h) bright-light (>4000 lux) stimuli on the phase and amplitude of the human circadian pacemaker, but theyExpand
Bright light resets the human circadian pacemaker independent of the timing of the sleep-wake cycle.
Human circadian rhythms were once thought to be insensitive to light, with synchronization to the 24-hour day accomplished either through social contacts or the sleep-wake schedule. Yet theExpand
Affective Discrimination of Stimuli That Cannot Be Recognized
Gratings of 8 cycle/deg were used, for these appeared to produce particularly strong adaptation. Such gratings approach the acuity limit of the short-wavelength pathway, which has poor spatialExpand
Spectral Responses of the Human Circadian System Depend on the Irradiance and Duration of Exposure to Light
Light resets the circadian clock through a non–image-forming receptor system—or so it was thought; now, cone photoreceptors are shown to also participate. Retinal Receptors Conspire to Keep Us AwakeExpand
Mathematical model of the human circadian system with two interacting oscillators.
Human subjects during extended isolation from environmental time cues show complex variations in timing and duration of sleep with a progressive pattern, which eventually results in rest-activity andExpand