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Developing measures of fatigue using an alcohol coparison to validate the effects of fatigue on performance

University of New South Wales, School of Psychology, Sydney, Australia.
Accident Analysis & Prevention (Impact Factor: 1.87). 06/2001; 33(3):313-26. DOI: 10.1016/S0001-4575(00)00045-2
Source: PubMed

ABSTRACT The effects of 28 h of sleep deprivation were compared with varying doses of alcohol up to 0.1% blood alcohol concentration (BAC) in the same subjects. The study was conducted in the laboratory. Twenty long-haul truck drivers and 19 people not employed as professional drivers acted as subjects. Tests were selected that were likely to be affected by fatigue, including simple reaction time, unstable tracking, dual task, Mackworth clock vigilance test, symbol digit coding, visual search, sequential spatial memory and logical reasoning. While performance effects were seen due to alcohol for all tests, sleep deprivation affected performance on most tests, but had no effect on performance on the visual search and logical reasoning tests. Some tests showed evidence of a circadian rhythm effect on performance, in particular, simple reaction time, dual task, Mackworth clock vigilance, and symbol digit coding, but only for response speed and not response accuracy. Drivers were slower but more accurate than controls on the symbol digit test, suggesting that they took a more conservative approach to performance of this test. This study demonstrated which tests are most sensitive to sleep deprivation and fatigue. The study therefore has established a set of tests that can be used in evaluations of fatigue and fatigue countermeasures.

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    • "It has been shown that sleep-dependent motor skill memory improvement was dependent on the nature of the skill to be learned (Cohen et al., 2005; Cohen and Robertson, 2007; Siengsukon and Boyd, 2008). In another study, perception, attention and memory were impaired by sleep deprivation, but visual search and logical reasoning tasks were not (Williamson et al., 2001). A deficit in perceptual classification ability in an information-integration task was observed for some, but not all, sleep-deprived individuals (Maddox et al., 2009). "
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    • "Comparison of performance deterioration due to sleepiness with performance deterioration caused by measured concentrations of alcohol consumption is one means of determining whether a particular level of sleepiness is likely to increase accident risk. This method has been utilized to determine that performance on a variety of tasks after 24 h awake is similar to performance at a BAC of 0.08–0.10% in a non-sleepdeprived state (Dawson and Reid, 1997; Lamond and Dawson, 1999; Williamson et al., 2001). This study evaluated specific symptoms as markers of sleepiness and performance impairment. "
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    • "This view has been called into question, because not all cognitive abilities are equally affected by sleep deprivation (Harrison and Horne 2000). In a battery of tasks, Williamson et al. (2000) found that perceptual, attentional and memory tasks were impaired by sleep deprivation, but visual search and logical reasoning tasks were not. Maddox et al. (2009) found deficits in perceptual classification ability in an information-integration task for some sleep-deprived *Corresponding author. "
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