Sleep restriction for the duration of a work week impairs multitasking performance

Area of Science:

• Occupational Health
• Sleep Science
• Human Factors Engineering

Background:

• Minimizing sleep-related human error is vital in safety-critical fields.
• Experimental data on sleep restriction (SR) informs the development of effective shift schedules.
• Understanding the impact of SR on performance is essential for workplace safety.

Purpose of the Study:

• To investigate the effects of sleep restriction on cognitive task performance and physiological sleepiness.
• To simulate real-world work demands under controlled sleep restriction conditions.
• To evaluate the recovery process following periods of sleep restriction.

Main Methods:

• Twenty healthy male volunteers (19-29 years) underwent a protocol including baseline, sleep restriction (4-h sleep), and recovery (8-h sleep) days.
• Multitask performance, physiological sleepiness (EEG/EOG), psychomotor vigilance, and subjective sleepiness (Karolinska Sleepiness Scale) were assessed daily.
• Sleep-wake rhythm was monitored throughout the experimental period.

Main Results:

• Multitask performance progressively deteriorated with prolonged sleep restriction and task duration.
• Significant group-level declines in performance and increased physiological sleepiness were observed.
• Individual differences in performance decrements were substantial, indicating varied susceptibility to sleep loss.
• Recovery of performance and sleepiness extended beyond the initial recovery sleep opportunities.

Conclusions:

• Consecutive days of sleep restriction negatively impact cognitive performance and increase sleepiness.
• Individual responses to sleep restriction vary, highlighting the need for personalized or flexible scheduling.
• Shift systems should be designed to prevent prolonged sleep restriction to mitigate risks in safety-critical domains.