The utility of automated measures of ocular metrics for detecting driver drowsiness during extended wakefulness.

Slowed eyelid closure coupled with increased duration and frequency of closure is associated with drowsiness. This study assessed the utility of two devices for automated measurement of slow eyelid closure in a standard poor performance condition (alcohol) and following 12-h sleep deprivation. Twenty-two healthy participants (mean age=20.

Specific sleepiness symptoms are indicators of performance impairment during sleep deprivation.

Drivers are not always aware that they are becoming impaired as a result of sleepiness. Using specific symptoms of sleepiness might assist with recognition of drowsiness related impairment and help drivers judge whether they are safe to drive a vehicle, however this has not been evaluated. In this study, 20 healthy volunteer professional drivers completed two randomized sessions in the laboratory - one under 24h of acute sleep deprivation, and one with alcohol.

The effect of sleep deprivation on BOLD activity elicited by a divided attention task.

Sleep loss, widespread in today's society and associated with a number of clinical conditions, has a detrimental effect on a variety of cognitive domains including attention. This study examined the sequelae of sleep deprivation upon BOLD fMRI activation during divided attention. Twelve healthy males completed two randomized sessions; one after 27 h of sleep deprivation and one after a normal night of sleep.

Transcutaneous measurement of carbon dioxide tension during extended monitoring: evaluation of accuracy and stability, and an algorithm for correcting calibration drift.

Background: When polysomnography is indicated in a patient with a presumed sleep disorder, continuous monitoring of arterial carbon dioxide tension (P(aCO(2))) is desirable, especially if nocturnal hypoventilation is suspected. Transcutaneous CO(2) monitors (P(tcCO(2))) provide a noninvasive correlate of P(aCO(2)), but their accuracy and stability over extended monitoring have been considered inadequate for the diagnosis of hypoventilation. We examined the stability and accuracy of P(tcCO(2)) measurements and the performance of a previously described linear interpolation technique designed to correct for calibration drift.