Tracking intermediate performance of vigilant attention using multiple eye metrics.

Vigilance deficits account for a substantial number of accidents and errors. Current techniques to detect vigilance impairment measure only the most severe level evident in eyelid closure and falling asleep, which is often too late to avoid an accident or error. The present study sought to identify ocular biometrics of intermediate impairment of vigilance and develop a new technique that could detect a range of deficits in vigilant attention (VA). Sixteen healthy adults performed well-validated Psychomotor Vigilance Test (PVT) for tracking vigilance attention while undergoing simultaneous recording of eye metrics every 2 hours during 38 hours of continuous wakefulness. A novel marker was found that measured VA when the eyes were open-the prevalence of microsaccades. Notably, the prevalence of microsaccades decreased in response to sleep deprivation and time-on-task. In addition, a novel algorithm for detecting multilevel VA was developed, which estimated performance on the PVT by integrating the novel marker with other eye-related indices. The novel algorithm also tracked changes in intermediate level of VA (specific reaction times in the PVT, i.e. 300-500 ms) during prolonged time-on-task and sleep deprivation, which had not been tracked previously by conventional techniques. The implication of the findings is that this novel algorithm, named "eye-metrical estimation version of the PVT: PVT-E," can be used to reduce human-error-related accidents caused by vigilance impairment even when its level is intermediate.

Ventricular fibrillation diagnosed during electrophysiological study for non-sustained tachycardia.

Ventricular fibrillation diagnoses such as Brugada syndrome pose a risk of sudden incapacitation or death in aircrew. This case report presents a 44-yr-old male fighter pilot who unexpectedly developed ventricular fibrillation (VF) during an electrophysiological study (EPS) prior to therapy for non-sustained ventricular tachycardia (nsVT). The initial aeromedical disposition for this case was "qualified for flying duties". with the restriction that he must fly with another pilot due to repeatedly observed nsVT. This pilot wanted to return to flight duty in single-seat aircraft without any restrictions. Therefore, this patient decided to undergo catheter therapy for nsVT. Unexpectedly, not VT but VF was induced by catheter manipulation during EPS. Pilsicainide-induced coved-type ST wave elevation consistent with Brugada syndrome was noted in this patient's electrocardiogram. He was ultimately disqualified due to the diagnosis of VF. This report suggests EPS on rare occasions may uncover another severe disease similar to this case report.

Mental health in Japanese members of the United Nations peacekeeping contingent in the Golan Heights: effects of deployment and the Middle East situation.

This study evaluates the mental health of Japan Self-Defense Force (JSDF) members of the peacekeeping contingent in the Golan Heights before and since the Second Gulf War between 1998 and 2003. Before the war, the General Health Questionnaire 30 (GHQ30) scores during and after duty tended to be lower than those before duty; all scores were lower than those of adult Japanese men in general. After the war, GHQ30 scores did not significantly change between before, during, and after duty. Manifest Anxiety Scale (MAS) scores were not significantly different between groups. Stressors identified included problems with foreign language and familial matters at home. Post war stressors included work content and relationships with collaborating foreign army units. These findings suggest that the mental health of contingent members remained stable, with some variation in mental health conditions influenced by the situation in the Middle East. This study suggests that the stable mental condition of JSDF personnel during their deployment in the absence of combat, and that this could be enhanced by education about mental health issues and by providing counseling support to their families.