Sleep deprivation: sensitivity comparison between a visuomotor tracking task and the Psychomotor Vigilance Test (PVT)

The Psychomotor Vigilance Test (PVT) is the most widely used test to assess vigilance, thanks to its short administration time and high sensitivity. However, as a reaction-time (RT) based test, it does not allow for continuous performance monitoring. This study evaluates the sensitivity of a continuous task, the Moving Target Tracking Task (MTTT), to sleep deprivation and compares its performance to that of the PVT. Twenty-five participants (5 women; mean age = 20.16 ± 2.07 years) completed a 10-minute MTTT and a 10-minute PVT at 9:30 PM and again at 5:30 AM after a night of total sleep deprivation. The MTTT consists of tracking a bouncing ball using a joystick, with the tracking error (TE) as the primary outcome measure. Wilcoxon tests and effect sizes (r) were computed to assess condition differences, and Spearman correlations evaluated relationships between variables from both tests. The MTTT outcome measures showed significant differences across conditions, with the TE standard deviation emerging as the most sensitive metric (r = 0.58). For the PVT, the mean 1/RT (r = 0.80), showed the largest effect size. No correlation was found between PVT and MTTT variables before sleep deprivation, but strong correlations appeared between most variables after it. While the MTTT detected vigilance decline, its sensitivity appeared limited to severe states, such as total sleep deprivation. In contrast, the PVT demonstrated higher sensitivity to sleep deprivation overall. Therefore, although the MTTT offers an advantage for continuous monitoring, the PVT remains the more effective test for detecting vigilance decline.