Blue light exposure therapy early in the morning may help the process of healing the impact of people with a mild traumatic brain injury, according to new research from the University of Arizona.
Daily exposure to blue light of the wavelength each morning helps re-enter the circadian rhythm so that people sleep better and more regularly. This is likely to be true for everyone, but recently we demonstrated it in people recovering from a mild traumatic brain injury, or mTBI. That improvement in sleep resulted in improvements in cognitive function, reduced daytime sleepiness and real brain repair. “
William D. “Scott” Killgore, professor of psychiatry at the Tucson School of Medicine
Killgore is the lead author of a new study published in the magazine. Neurobiology of the disease.
Mild traumatic brain injuries, or concussions, are often the result of falls, fights, car accidents and sports participation. Among other threats, military personnel may also experience mTBI from exposure to explosive explosions: shock waves hit the soft tissue of the intestine and push an explosion of pressure into the brain, causing microscopic damage to blood vessels and brain tissue, Killgore said.
“Your brain has the consistency of a thick jelly,” he said. “Imagine a bowl of jelly hit by a blow or hitting the steering wheel in a car accident. What are you doing? Absorbs the impact and bounces. During that impact, microscopic brain cells become thinner than a lock of hair. It stretches. , tear and tear easily from force. “
Those with a concussion or mTBI may see stars momentarily, become disoriented or even lose consciousness briefly after the injury; However, loss of consciousness does not always occur and many people who suffer a concussion can get away without realizing that they have a mild brain injury, according to Killgore. Headaches, attention problems and mental confusion are commonly reported after head injuries and may persist for weeks or months for some people.
Few, if any, effective treatments for mTBI exist. The U.S. Army Medical Research and Development Command UU. He funded the research to find alternatives to the medicinal recovery methods of mTBI.
“About 50% of people with mTBI also complain that they have trouble sleeping after an injury,” Killgore said.
Recent research has shown that the brain is repaired during sleep, so Killgore and his co-authors, John Vanuk, Bradley Shane, Mareen Weber and Sahil Bajaj, all from the Department of Psychiatry, sought to determine whether sleep improvement led to recovery faster .
In a randomized clinical trial, adults with mTBI used a cube-like device that illuminates bright blue light (with a maximum wavelength of 469 nm) to participants from their desk or tables for 30 minutes early each morning for six weeks Control groups were exposed to bright amber light.
“Blue light suppresses brain production of a chemical called melatonin,” said Killgore. “You don’t want melatonin in the morning because it makes you sleepy and prepares your brain to sleep. When you’re exposed to blue light in the morning, change your brain’s biological clock so that at night, melatonin is activated earlier and helps you fall asleep and stay asleep. “
People get the most restful sleep when aligned with their natural circadian rhythm of melatonin, the body’s sleep-wake cycle associated with night and day.
“The circadian rhythm is one of the most powerful influences on human behavior,” said Killgore. “Humans evolved on a planet for millions of years with a 24-hour light / dark cycle, and that is deeply rooted in all our cells. If we can make him sleep regularly, at the same time every day, that’s much better because the body and the brain can more effectively coordinate all these repair processes. “
As a result of the blue light treatment, the participants fell asleep and woke up an average of one hour before the trial and were less sleepy during the day. Participants improved their speed and efficiency in brain processing and showed an increase in volume in the pulvinar nucleus, an area of the brain responsible for visual attention. Neural connections and the flow of communication between the pulvinar nucleus and other parts of the brain that drive alertness and cognition were also strengthened.
“We believe that we are facilitating the healing of the brain by promoting better sleep and circadian alignment, and as these systems heal, these areas of the brain communicate with each other more effectively. That could be what translates into improvements in cognition and less daytime sleepiness, “said Killgore said.
The blue light of computers, smartphones and TV screens often gives the blue light a bad reputation. But according to Killgore, “when it comes to light, time is critical. Light is not necessarily good or bad in itself. Like caffeine, it all comes down to when you use it. It can be terrible for you to sleep if you’re having coffee at 10 o’clock at night, but it can be good for your alertness if you drink it in the morning. “
He and his team plan to continue their research to see if blue light improves sleep quality and how light therapy could affect emotional and psychiatric disorders. Killgore believes that most people, whether injured or healthy, could benefit from properly programmed morning blue light exposure, a theory he hopes to demonstrate with certainty in future studies.
Killgore, W.D.S. et al. (2020) A randomized, double-blind, placebo-controlled trial of blue wavelength light exposure in sleep and recovery of brain structure, function and cognition after mild traumatic brain injury. Neurobiology of the disease. doi.org/10.1016/j.nbd.2019.104679.