Researchers have found that exposure to short wavelength, or blue light, immediately improves alertness and performance.
Lead researcher Shadab Rahman, PhD, a researcher in BWH's Division of Sleep Medicine, said that their previous research has shown that blue light is able to improve alertness during the night, but their new data demonstrates that these effects also extend to daytime light exposure, asserting that these findings demonstrate that prolonged blue light exposure during the day has an alerting effect.
In order to determine which wavelengths of light were most effective in warding off fatigue, the BWH researchers teamed with George Brainard, PhD, a professor of neurology at Thomas Jefferson University, who developed the specialized light equipment used in the study.
Researchers compared the effects of blue light with exposure to an equal amount of green light on alertness and performance in 16 study participants for 6.5 hours over a day. Participants then rated how sleepy they felt, had their reaction times measured and wore electrodes to assess changes in brain activity patterns during the light exposure.
The researchers found that participants exposed to blue light consistently rated themselves as less sleepy, had quicker reaction times and fewer lapses of attention during the performance tests compared to those who were exposed to green light. They also showed changes in brain activity patterns that indicated a more alert state.
The findings have been published in the journal Sleep.