When you think of light therapy, springtime sunshine after a long winter or the infamous tanning bed is likely pictured, but safe, harnessed light has long been coveted for its therapeutic effects. Bright light therapy, or phototherapy, is a well-known and widely used treatment. Photobiomodulation (PBM), previously known as Low Level Laser Therapy (LLLT) was unintentionally discovered in 1967. It is the use of red or near-infrared light to stimulate, heal, regenerate, and protect tissue that has either been injured, is degenerating, or else is at risk of dying.
One easily measurable reaction to light is the increase of blood flow. Dr. Michael R. Hamblin, Principal Investigator at the Wellman Center for Photomedicine, believes that Photobiomodulation stimulates cells to produce more ADP, the energy that powers cellular activity. "The mechanisms are manifold," Hamblin explained. "Clearly you're boosting metabolism - ATP, oxygen consumption, brain energy. You're improving cerebral blood flow. But you're also stimulating the formation of new brain cells and the formation of new connections between existing brain cells. And together, these two processes comprise neuroplasticity, basically the brain's ability to reorganize itself, to repair itself."
In a study performed in Japan (24 years of Experience of Low Level Laser Therapy (LLLT) for Children with Cerebral Palsy, Yoshimi Asagai, 2016), laser irradiation performed before a slow stretching exercise suppressed the pain normally associated with stretching. Additionally, patients with severe cases of cerebral palsy can experience fractures and osteoporosis. After LLLT, Asagai’s patients showed an increase in bone density and improved bone thickness.
Margaret Naeser, a research professor of neurology at the Boston University School of Medicine has tested PBM in human subjects in “an open protocol study that examined whether scalp application of red and near infrared (NIR) light could improve cognition in patients with chronic, mild traumatic brain injury (mTBI).” At the end of the study, participants showed an increase in their ability to sleep, fewer PTSD symptoms, better social function, and improved occupational and interpersonal interactions. The patients involved in these studies were followed clinically after their treatment and maintained their initial clinical benefits after a relatively short course of treatments
Near-Infrared (NIR) Light therapy (NIL or NILT) is newer to the scientific research arena as compared to the bright light variety but has shown great potential for combating inflammation and other noteworthy conditions such as traumatic brain injury (TBI). This is because cell and tissue types have their own unique light absorption abilities: surface skin areas are treatable with a blue wavelength and deeper tissues are reached more readily by the color wavelengths made available through NIR.
Light therapy is a bright spot in medical research today. Photobiomodulation clearly has scientifically proven healing abilities. Many scientists believe PBM use for brain disorders will become one of the most important medical applications of light therapy in the coming decades.