Circadian Potency Spectrum in Light-Adapted Humans.

Light exposure at night can disrupt the circadian timing of cellular processes and is associated with a broad range of health disorders. To spectrally engineer lighting which minimizes circadian disruption at night it is necessary to define the precise spectral sensitivity of the human circadian system. Prior attempts have used short monochromatic light exposures in dark-adapted human subjects, or dark-adapted isolated retina or melanopsin.

Circadian Potency Spectrum with Extended Exposure to Polychromatic White LED Light under Workplace Conditions.

Electric light has enabled humans to conquer the night, but light exposure at night can disrupt the circadian timing system and is associated with a diverse range of health disorders. To provide adequate lighting for visual tasks without disrupting the human circadian timing system, a precise definition of circadian spectral sensitivity is required. Prior attempts to define the circadian spectral sensitivity curve have used short (≤90-min) monochromatic light exposures in dark-adapted human subjects or in vitro dark-adapted isolated retina or melanopsin.

Circadian alertness simulator for fatigue risk assessment in transportation: application to reduce frequency and severity of truck accidents.

The Circadian Alertness Simulator (CAS) was developed as a practical tool for assessing the risk of diminished alertness at work. Applications of CAS include assessment of operational fatigue risk, work schedule optimization, and fatigue-related accident investigation. Based on the documented work schedules of employees, sleep and alertness patterns are estimated and a cumulative fatigue score is calculated.

EEG delta activity during undisturbed sleep in the squirrel monkey.

The squirrel monkey (Saimiri sciureus) exhibits a robust daily rhythm of sleep-wakefulness that is under circadian control, but the nature of homeostatic sleep regulation in this diurnal primate is poorly understood. Since delta frequency (0.5-2.