The role of sleep deprivation and fatigue in the perception of task difficulty and use of heuristics

Objectives: This study investigated the effects of sleep deprivation on perception of task difficulty and use of heuristics (mental shortcuts) compared to naturally-experienced sleep at home. Methods: Undergraduate students were screened and assigned through block-random assignment to Naturally-Experienced Sleep (NES; n=19) or Total Sleep Deprivation (TSD; n=20). The next morning, reported fatigue, perception of task difficulty, and use of “what-is-beautiful-is-good,” “greedy algorithm,” and “speed-accuracy trade-off ” heuristics were assessed. Results: NES slept for an average of 354.74 minutes (SD=72.84), or 5.91 hours. TSD rated a reading task as significantly more difficult and requiring more time than NES. TSD was significantly more likely to use the greedy algorithm heuristic by skipping instructions and the what-is-beautiful-is-good heuristic by rating an unattractive consumer item with a favorable review as poor quality. Those in Total Sleep Deprivation who chose more difficult math problems made this selection to finish the task more quickly in findings approaching significance, indicating use of the speed-accuracy trade-off heuristic. Collapsed across conditions, self-reported fatigue predicted greater perceived difficulty in both the reading task and a visuo-motor task, higher quality rating for the attractive consumer item, and lower quality rating for the unattractive consumer item. Conclusions: Findings indicate sleep deprivation and fatigue increase perceptions of task difficulty, promote skipping instructions, and impair systematic evaluation of unappealing stimuli compared to naturally-experienced sleep

The effects of sleep loss on capacity and effort

AbstractSleep loss appears to affect the capacity for performance and access to energetic resources. This paper reviews research examining the physical substrates referred to as resource capacity, the role of sleep in protecting that capacity and the reaction of the system as it attempts to respond with effort to overcome the limitations on capacity caused by sleep loss. Effort is the extent to which an organism will exert itself beyond basic levels of functioning or attempt alternative strategies to maintain performance. The purpose of this review is to bring together research across sleep disciplines to clarify the substrates that constitute and influence capacity for performance, consider how the loss of sleep influences access to those resources, examine cortical, physiological, perceptual, behavioral and subjective effort responses and consider how these responses reflect a system reacting to changes in the resource environment. When sleep deprived, the ability to perform tasks that require additional energy is impaired and the ability of the system to overcome the deficiencies caused by sleep loss is limited. Taking on tasks that require effort including school work, meal preparation, pulling off the road to nap when driving drowsy appear to be more challenging during sleep loss. Sleep loss impacts the effort-related choices we make and those choices may influence our health and safety