A single 30 min. exposure to blue-wavelength light can increase subsequent activation in brain regions critical for successful working memory performance and improve response times, a new study suggests.
Previous studies have shown that exposure to blue light, which is similar to the type of light you get on a bright sunny day, leads to increases in alertness and better performance on reaction time tasks, while being exposed.
“Our study adds to this literature by showing that exposure to 30 minutes of blue light in comparison to 30 minutes of amber light led to subsequently better performance on a cognitive task 40 minutes after the blue-light exposure period had ended,” Dr Alkozei, PhD, postdoctoral fellow in the Department of Psychiatry, University of Arizona in Tucson, told MedScape News.
The findings were presented at SLEEP 2016: the 30th Anniversary Meeting of the Associated Professional Sleep Societies.
With increases in cognitive load, the blue-light group had faster reaction times and more efficient responding (ie, they answered more items correctly per second).
The importance of this study is that it showed there was a lasting benefit, not just momentary.
In other words, it may be beneficial to use blue light before having to engage in tasks that require you to stay alert and react quickly, such as testing situations.
The melanopsin receptors that are providing light information to the circadian system is most sensitive to blue light, so it’s never going to be surprising that blue light has a strong effect on biological rhythms.
[SOURCE: SLEEP 2016: 30th Anniversary Meeting of the Associated Professional Sleep Societies. Abstract 0072. Presented June 12, 2016].