Summary
Exposure to full-spectrum bright light (~900 lx, 4000 K) during simulated night shifts (23:00–07:00 h) improved cognitive flexibility (reversal learning) compared to standard lighting (~90 lx), suggesting bright light interventions can benefit night workers beyond simply maintaining vigilant attention. Lighting designers and healthcare facility planners should consider high-illuminance, cool-spectrum lighting in night-shift work environments to preserve workers' higher-order cognitive functioning.
Key Findings
- Reversal learning task performance declined towards the end of night shifts (04:50 h vs. 00:20 h) under both bright and standard light conditions.
- Bright light (~900 lx, 4000 K full-spectrum) improved reversal learning task performance at 04:50 h compared to standard light (~90 lx) at the same time point.
- Counterbalanced crossover design with three consecutive simulated night shifts (NCT03203538); participants served as their own controls.
Categories
Shift Work & Staff Wellbeing: Bright light intervention during simulated night shifts improved cognitive flexibility, directly relevant to healthcare and other shift workers.
Workplace Performance: Study demonstrates that bright light (~900 lx, 4000 K) mitigates cognitive performance deficits during night work compared to standard lighting (~90 lx).
Sleep & Circadian Health: Simulated night shift protocol examines circadian misalignment effects on cognitive function and bright light as a countermeasure.
Author(s)
E Sunde, J Mrdalj, TT Pedersen, B Bjorvatn
Publication Year
2022
Number of Citations
1
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