Blue-light exposure therapy may hold potential to improve concussion recovery
A team of researchers utilized blue-light exposure therapy to reset the sleeping patterns of individuals who had sustained a concussion to investigate its effect on recovery of brain structure, connectivity and cognitive performance.
New research conducted by a team from the University of Arizona (AZ, USA) demonstrated that early-morning, blue-light exposure therapy may improve recovery from mild traumatic brain injury (mTBI).
Recent research has discovered that the brain repairs itself during sleep, however, approximately 50% of individuals with mTBI report to have sleep problems after injury. Therefore, the authors of the current study aimed to investigate whether improved sleep resulted in faster recovery.
The team carried out a randomized clinical trial to investigate the effects of bright, blue light on the sleep of individuals with mTBI. The participants were asked to use a cube-like device, which shines blue light at their desk for 30 minutes per day each morning for six weeks. The control group was exposed to amber light.
Following the blue light treatment, participants fell asleep and woke an average of one hour earlier than before the trial and were less sleepy during the day. This resulted in improved speed and efficiency in brain processing. Further, communication between the pulvinar nucleus – an area responsible for visual attention – and other parts of the brain associated with alertness and cognition was observed to be strengthened.
“Daily exposure to blue wavelength light each morning helps to re-entrain the circadian rhythm so that people get better, more regular sleep. This is likely true for everybody, but we recently demonstrated it in people recovering from mTBI. That improvement in sleep was translated into improvements in cognitive function, reduced daytime sleepiness and actual brain repair,” commented lead study author, William D.S. Killgore (University of Arizona).
Symptoms such as headaches and attention problems are commonly reported by individuals who have experienced a concussion and can persist for months. Currently, there is a lack of effective treatment options for mTBI, which led to The US Army Medical Research and Development Command funding research to find alternatives to medicinal methods of recovery.
“Blue light suppresses brain production of a chemical called melatonin,” Killgore commented. “You don’t want melatonin in the morning because it makes you drowsy and prepares the brain to sleep. When you are exposed to blue light in the morning it shifts your brain’s biological clock, so that in the evening your melatonin will kick in earlier and help you to fall asleep and stay asleep.”
Sleep is most restorative when it aligns with the natural circadian rhythm of melatonin. Killgore reported that sleeping regularly each day is better for both the brain and body, as they can effectively co-ordinate their recovery processes.
“We think we’re facilitating brain healing by promoting better sleep and circadian alignment, and as these systems heal, these brain areas are communicating with each other more effectively. That could be what’s translating into improvements in cognition and less daytime sleepiness,” Killgore explained.
Blue light from computers, smartphones and TV screens often gives blue light a bad rap, however, Killgore emphasized that when it comes to light, timing is critical.
The research team plan to further their research by investigating how light therapy may affect emotional and psychiatric disorders. Killgore believes that this light therapy could benefit most people and not just those who have experience a brain injury.
Source: Killgore WDS, Vanuk JR, Shane BR, Weber M and Bajaj S. A randomized, double-blind, placebo-controlled trial of blue wavelength light exposure on sleep and recovery of brain structure, function, and cognition following mild traumatic brain injury. Neurobiol. Dis. doi:10.1016/j.nbd.2019.104679 (2019) (Epub ahead of print); https://uanews.arizona.edu/story/blue-light-can-help-heal-mild-traumatic-brain-injury