Figueiro Mariana G, Sahin Levent, Wood Brittany, Plitnick Barbara
Lighting Research Center, Rensselaer Polytechnic Institute, Troy, NY, USA
Lighting Research Center, Rensselaer Polytechnic Institute, Troy, NY, USA.
Biol Res Nurs. 2016 Jan;18(1):90-100. doi: 10.1177/1099800415572873. Epub 2015 Feb 19.
Rotating-shift workers, particularly those working at night, are likely to experience sleepiness, decreased productivity, and impaired safety while on the job. Light at night has been shown to have acute alerting effects, reduce sleepiness, and improve performance. However, light at night can also suppress melatonin and induce circadian disruption, both of which have been linked to increased health risks. Previous studies have shown that long-wavelength (red) light exposure increases objective and subjective measures of alertness at night, without suppressing nocturnal melatonin. This study investigated whether exposure to red light at night would not only increase measures of alertness but also improve performance. It was hypothesized that exposure to both red (630 nm) and white (2,568 K) lights would improve performance but that only white light would significantly affect melatonin levels. Seventeen individuals participated in a 3-week, within-subjects, nighttime laboratory study. Compared to remaining in dim light, participants had significantly faster reaction times in the GO/NOGO test after exposure to both red light and white light. Compared to dim light exposure, power in the alpha and alpha-theta regions was significantly decreased after exposure to red light. Melatonin levels were significantly suppressed by white light only. Results show that not only can red light improve measures of alertness, but it can also improve certain types of performance at night without affecting melatonin levels. These findings could have significant practical applications for nurses; red light could help nurses working rotating shifts maintain nighttime alertness, without suppressing melatonin or changing their circadian phase.
轮班工作者，尤其是那些从事夜间工作的人，在工作时可能会感到困倦、工作效率下降以及安全受到影响。夜间光照已被证明具有急性警觉作用，可减少困倦并提高工作表现。然而，夜间光照也会抑制褪黑素并导致昼夜节律紊乱，这两者都与健康风险增加有关。先前的研究表明，夜间暴露于长波长（红色）光下可提高夜间警觉性的客观和主观指标，而不会抑制夜间褪黑素。本研究调查了夜间暴露于红光下是否不仅会提高警觉性指标，还会改善工作表现。研究假设，暴露于红色（630纳米）和白色（2568开尔文）光下都会改善工作表现，但只有白光会显著影响褪黑素水平。17名个体参与了一项为期3周的、受试者内的夜间实验室研究。与处于暗光环境相比，参与者在暴露于红光和白光后，在“是/否”测试中的反应时间显著更快。与暴露于暗光相比，暴露于红光后，α波和α-θ波区域的功率显著降低。仅白光显著抑制了褪黑素水平。结果表明，红光不仅可以提高警觉性指标，还可以在不影响褪黑素水平的情况下改善夜间的某些类型的工作表现。这些发现可能对护士有重大的实际应用价值；红光可以帮助轮班工作的护士保持夜间警觉，而不会抑制褪黑素或改变他们的昼夜节律。
