Shining The (blue) Light on mTBI
Updated: Feb 18, 2020
mTBI, or mild traumatic brain injury, are often the results of a fall, collision, or fight. mTBI's can be seen in athletes, soldiers, and any typical individual. While mTBI's can come with a long list of symptoms, change in sleep habits and quality of sleep are seen in 50% of these patients.
William D. “Scott” Killgore, psychiatry professor in the College of Medicine Tucson, conducted a randomized clinical trial utilizing blue light for sleep difficulties. Killgore exposed adults with mTBI to a blue lightbox with a peak wavelength of 469 nm, for 30 minutes in the early morning. Control groups were exposed to an amber lightbox for the same amount of time. Results showed that blue light participants reported less daytime sleepiness, and the ability to wake up earlier without subsequent fatigue or feeling the need for more sleep.
Blue light is often presented in the context of phones, televisions, and computer screens as a damaging and negative side effect of screen use. Killgore recognizes the overexposure of blue light but emphasizes how critical the timing of the light exposure is in providing a maximum therapeutic effect.
The aim of the blue light therapy is to retrain your circadian rhythm, an internal process that also utilizes external cues such as sunlight to moderate our wakefulness and sleepiness. Within this process is melatonin, a hormone released by the pineal gland to cue the need for sleep. Blue light triggers the suppression of melatonin, the suspected culprit for daytime sleepiness in mTBI patients, as the body is no longer properly mediating melatonin release due to insomnia, restless sleep, or daytime sleep. Blue light can suppress the release of the hormone until the proper hour, prompting faster, deeper, and higher quality sleep.
With an increased sleep quality, Killgore believes that healing from mTBI is more of a possibility, and at a faster rate than those who struggle with sleep after their injury.