Impact of Monetary Incentives on Cognitive Performance and Error Monitoring following Sleep Deprivation (original) (raw)

NESS, ARE COMMON IN MODERN SOCIETY. SLEEP loss and sleepiness contribute significantly to performance decrements and accidents, such as motor vehicle crashes and work error-related damages. 1 Performance decrements after sleep loss are generally attributed to attention deficit, and this proposition is supported by several behavior, 2,3 electrophysiologic, 4,5 and functional brain imaging studies. 6 Attention is a multidimensional cognitive process, and the results of several studies have suggested that sleep loss induces selective impairment of attention processes, particularly the top-down attention control processes that rely on the frontal lobe. 2,3,6 This corresponds with the view of Horne 7 that frontal lobe functions are sensitive to total sleep loss. The frontal lobe is critically involved in executive function, including the ability to plan or set goals, supervisory attention processes, response inhibition, and action monitoring, such as error detection and conflict processing. A series of recent studies conducted by us 8-10 and others 11,12 have shown that all components of error monitoring, including error detection, error correction, and posterror speed and accuracy adjustments, are impaired following sleep deprivation. Thus, sleep deprivation-related performance decrements and accidents appear to result from deficits in both attention processes and performance monitoring, particularly error monitoring in the latter. The results of previous studies have suggested that the decline in vigilance task performance during sleep deprivation is in part related to reduced motivation. 13-15 The feedback of the knowledge of results 14,15 and monetary rewards 13 reduce some negative effects of sleep loss on vigilance task performance. Vigilance is commonly defined as sustained attention or tonic alertness. 1 Given that the reduction of vigilance related to a low arousal level gives rise to performance decrements following sleep deprivation, monetary incentives are thought to have general effects on the performance of vigilance tasks, such as effects related to arousal, alertness, or mental effort. 14-16 Additionally, monetary incentives have recently been proposed to selectively influence the top-down attention mechanisms in the performance of tasks that require a high degree of top-down attention control processes. 17-20 A previous study used a cued attention task in which subjects responded to targets preceded by spatially valid, invalid, or neutral (noninformative) cues and illustrated that monetary incentives enhanced the response speed in the case of the trials with the valid and invalid cues but not those with the neutral cues. 19 Furthermore, a recent study has shown that a continuous 2-hour performance of a task that requires a high degree of cognitive control results in performance reduction in terms of the response speed, accuracy, and stability. 21 Performance decrements due to prolonged task performance are accompanied by a decrease in the brain activity, including the amplitude of the contingent negative variation