Changes in higher order cognitive function between four watch keeping schedules

Area of Science:

• Maritime Safety
• Human Factors
• Cognitive Psychology

Background:

• Maritime industries rely on 24/7 watchkeeping schedules for crew safety.
• Existing schedules can be fatiguing, negatively impacting vigilant attention.
• The effects of alternative, sleep-optimized schedules on higher-order cognitive function are not well understood.

Purpose of the Study:

• To investigate the impact of four different watchkeeping schedules on higher-order cognitive functions in maritime personnel.
• To assess cognitive performance using tasks relevant to real-world maritime operations.
• To compare the stability of cognitive function across different schedules.

Main Methods:

• A 10-day laboratory study involving 27 participants.
• Comparison of four watchkeeping schedules: 8/8/4/4 (A), 6/6 (B), 4/4/4/4/4/4 with early sleep (C), and 4/4/4/4/4/4 with late sleep (D).
• Assessment of visual scanning, learning, working memory, mental flexibility, and visuomotor control 2-3 times daily while 'on watch'.

Main Results:

• Cognitive function was ranked lowest across most tasks in schedule B (6/6).
• The stability of higher-order cognitive function was poorest throughout the waking day in schedule A (8/8/4/4).
• Significant variability in cognitive capacities was observed across the different schedules.

Conclusions:

• Watchkeeping schedules significantly influence higher-order cognitive functions in maritime settings.
• Schedule B appears detrimental to overall cognitive performance.
• Schedule A may lead to greater fluctuations in cognitive stability during watch periods.
• Findings underscore the importance of carefully considering schedule design to optimize cognitive function and safety at sea.