Sleep deprivation field studies

Of interest for this chapter, however, is the ability of individuals to accurately assess their internal state of motivation during sleep deprivation conditions. Unfortunately, research in the sleep deprivation field has not yet addressed this issue. It would seem that questions assessing individuals motivation to complete a task might be related to, yet different from, their subjective assessment of effort. Future studies could be designed to investigate the relationship between sleep deprivation and motivation to complete a task and the relationship of motivation to subjective effort. 

The Walter Reed Army Institute of Research s Department of Behavioral Biology has developed a field-deployable version of a commercial Psychomotor Vigilance Task (PVT) that has been widely used in sleep research. The software runs on handheld PDAs running the Palm Operating System (Palm OS). It is modeled after the simple reaction time task of Wilkinson and Houghton,57 as modified by Dinges and Powell.58 The Palm OS version incorporates additional stimulus, feedback, control, and data options developed by Dr. Thome. In laboratory studies, performance on the PDA task has been shown to be sensitive to time-on-task fatigue effects, sleep deprivation, and circadian variation.18 Field studies have utilized the PVT to measure the efficacy of caffeine gum as a sleep loss countermeasure. 

Relatively few studies have examined the effects of sleep deprivation on athletic performance in the field and even fewer are associated with a meaningful competitive event. Therefore, indirect evidence from military research and subjective reports from elite athletes participating in ultraendurance races will also be reviewed. 

In conclusion, field studies are limited in number and precision. High variance in study design no doubt contributes to inconsistencies in findings. Perhaps the best evidence for athletic performance decrement secondary to significant sleep deprivation is the complete absence of any study that has deliberately deprived elite athletes of sleep prior to a meaningful competitive event. There have been ample opportunities, but apparently no volunteers. 

Thus, Rogd s study demonstrates the effects of different aspects of fatigue. Sleep deprivation causes a generalized reduction in attention as manifest in a uniform reduction in target detection everywhere in the field (Figure 14-5). Time-on-task, in contrast, is associated with a selective reduction in attention, in which the deterioration is in direct relation to the deviation of the targets from the center of the visual field. 

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