A method for resetting the phase of the human circadian clock and for enhancing alertness and performance in humans. The method involves the application of non-solar photic stimulation, in the range of 15 to 150,000 lux, to any non-ocular region of the human body during wakefulness or during sleep. Preferably, the photic stimulation has a wavelength within the visible spectrum (.about.400-750 nm). The method can be used to both delay and advance the circadian clock according to a phase response curve (PRC). The method may also be used for acute/immediate enhancement of alertness and performance. The method is applicable to alleviation of problems associated with "jet-lag", shift work sleep disturbance, and other sleep disturbances involving misalignment of circadian rhythms. The method provides a novel technique for shifting the phase of the circadian clock, and enhancing alertness and performance, using existing, or newly-developed devices.
This application claims the benefit of U.S. Provisional Application No. 60/046,188 filed May 12, 1997 now abandoned and U.S. Provisional Application No. 60/072,121 filed Jan. 22, 1998 now abandoned.
Alertness level is predicted on computers or sliding charts by relationship of sleep drives and wake drives, which are separately moved relative to destination time and time zone differential. Wake drives are moved with home time. Sleep drive is moved with bedtime and sleep debt relative to times and a sleep debt scale, respectively. Resulting displays predict alertness, drowsiness, wake drives in relation to sleep drives, best bedtime, sleep debt and illumination recommendations.
A device is provided for treating a circadian rhythm disorder in a subject. The device includes a plurality of light emitting diodes (LED's), preferably blue to green; a mounting to which the LED's are connected: a material for positioning the LED's within 3 cm of the subject, with an orientation toward the subject; a portable power supply electrically connected to the LED's; and a control connected to the LED's for altering the operation of the LED's. The device is sufficiently light and compact to be comfortably worn by the subject. One or more such devices are used to deliver light to a subject's retinas, to the subject's vascular tissue, or simultaneously to both the retinas and the vascular tissue. For illumination of the retina, small chip-type LED's are integrated into the frames of eyeglasses and positioned to direct light into the eyes of the subject. For illumination of the vascular tissue, an array of lens or chip type LED's are contained in a casing that is secured against the skin of the subject. The devices can be used independently of each other, or can be used in combination for more effective and/or flexible treatment.
A light therapy device is taught including a light emitting assembly having light emitting diodes (LEDs) as a light source. The light emitting assembly capable of generating 2,500 lux to 7,500 lux at 12 inches.
A method for evaluating the effectiveness of a person to perform a task based on his/her previous or predicted sleep activity is provided. The method can be used to predict changes in task effectiveness at any time of day, based upon numerous patterns of sleep and activity, either experienced or planned for the future. The method take into account progressive increases in sleep deprivation, the effects of the time of day on performance, and changes in the time when a person sleeps and works. The method also accounts for the quality of a sleep interval and a person's sleep inertia, the temporary slowing of performance immediately after awakening. The method is homeostatic. Gradual decreases in sleep debt decrease sleep intensity. Progressive increases in sleep debt produced by extended periods of less than optimal levels of sleep lead to increased sleep intensity. As a result the method can predict the normal decline in sleep intensity during the sleep period and the normal equilibrium of performance under less than optimal schedules of sleep.
Alertness level is predicted on computers or sliding charts by relationship of sleep drives and wake drives, which are separately moved relative to destination time and time zone differential. Wake drives are moved with home time. Sleep drive is moved with bedtime and sleep debt relative to times and a sleep debt scale, respectively. Resulting displays predict alertness, drowsiness, wake drives in relation to sleep drives, best bedtime, sleep debt and illumination recommendations.
