How blue-light blocking glasses affects recovery from jetlag

Undergraduates: Rachael Kang, Kenny Le Tate Halverson, Mian-Li Ong Eric Youngstrom

Faculty Advisor: Rachael Kang
Department: Psychology & Neuroscience

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Circadian rhythms, which are closely related to mood and energy, are controlled by blue light and can be disrupted by transmeridian travel. This study evaluates the efficacy of blue-light blocking glasses in reducing sleepiness and negative affect associated with jetlag. 18 participants were enrolled from a summer program at Korea University in Seoul, South Korea. They were randomly placed into either (a) blue-light blocking glasses group or (b) no glasses group. Participants were followed before and after their travel home, taking the Stanford Sleepiness Scale to measure sleepiness, and the Positive and Negative Affect Scale to measure mood. Independent samples t-tests indicated no significant differences between the sleepiness scores of the two groups (p>.01), and no significant difference in positive affect scores between the glasses group (Mp=25.55, SDp = 7.84) and the no glasses group (Mp=22.16, SDp=5.97); tp(117)=2.59, p=.011. There was a significant difference between the negative affect scores of the glasses group (Mn=11.98,SDn=3.61) and the no glasses group (Mn=13.92, SDn=3.74); tn(119)=-2.72, p=.008. These results suggest that while the overall sleepiness of the participants remained unaffected by the blue-light blocking glasses, their affect was less negative. The glasses triggering the release of melatonin could be consistent with this. The individual would receive the benefits of the increased melatonin in their systems, without actually getting more sleep.