Performance trends during sleep deprivation on a tilt-based control task

BACKGROUND: Understanding human behavior under the effects of sleep deprivation allows for the mitigation of risk due to reduced performance. To further this goal, this study investigated the effects of short-term sleep deprivation using a tilt-based control device and examined whether existing user models accurately predict targeting performance. METHODS: A task in which the user tilts a surface to roll a ball into a target was developed to examine motor performance. A model was built to predict human performance for this task under various levels of sleep deprivation. Every 2 h, 10 subjects completed the task until they reached 24 h of wakefulness. Performance measurements of this task, which were based on Fitts' law, included movement time, task throughput, and time intercept. RESULTS: The model predicted significant performance decrements over the 24-h period with an increase in movement time (R² = 0.61), a decrease in throughput (R² = 0.57), and an increase in time intercept (R² = 0.60). However, it was found that in experimental trials there was no significant change in movement time (R² = 0.11), throughput (R² = 0.15), or time intercept (R² = 0.27). DISCUSSION: The results found were unexpected as performance decrement is frequently reported during sleep deprivation. These findings suggest a reexamination of the initial thought of sleep loss leading to a decrement in all aspects of performance.