Publication Date

Summer 2022

Degree Type


Degree Name

Master of Science (MS)


Human Factors/Ergonomics


Cary S. Feria

Subject Areas



Obtaining a sufficient amount of sleep each night is necessary for maintaining physiological and cognitive functioning. Chronic sleep restriction (CSR) occurs when a reduced amount of sleep is obtained each night for consecutive nights. The psychomotor vigilance task (PVT) is a simple reaction time (RT) test used for detecting the effects of sleep loss. The present study aimed to examine the effects of one week of CSR, compared to one week of sleep satiation, on NASA PVT+ outcomes and multiple object tracking (MOT) accuracy. The NASA PVT+ is a mobile application where participants respond to a target stimulus by tapping the screen as quickly as possible. The MOT task requires a cued subset of identical objects to be tracked as all of the objects move about the display (in the present study there were either 4, 5, or 6 targets among 12 total objects), but it has not been assessed in relation to sleep loss. Participants underwent a week of CSR and a week of sleep satiation at home and reported to the laboratory for assessment at the end of each week. For the NASA PVT+, the week of CSR was associated with slower RTs, reduced response speeds, and a higher number of lapses. For MOT, there was no difference in tracking accuracy following CSR or sleep satiation when the three tracking conditions were analyzed together. However, additional analyses found that performance was worse in the high load condition (i.e., 6-targets) following CSR but that there was no effect of CSR for the lower loads (i.e., 4- or 5-targets) when analyzed separately. These results suggest that CSR preferentially diminishes sustained attention outcomes and performance on tasks that impose a high cognitive load.

Available for download on Monday, October 11, 2027