In recent years, near-infrared phototherapy (NIR phototherapy) has become a focus in neuroscience, especially regarding its role in the recovery from mild traumatic brain injury (mTBI).

New research suggests that 810nm light, within the near-infrared spectrum, significantly enhances functional recovery post-mTBI by diminishing markers linked to apoptosis and the activation of astrocytes and microglia, hinting at its regenerative therapy potential.

Photobiomodulation: Facilitating the Brain's Self-Healing Process

Mild traumatic brain injury (mTBI), commonly caused by external forces like traffic accidents, sports injuries, or falls, may not lead to significant structural damage but can significantly affect brain function. Symptoms such as memory decline, lack of concentration, and emotional fluctuations can last for weeks to months.

Photobiomodulation (PBM) is a light therapy that utilizes red or near-infrared light (600-1000nm). The mechanism is thought to engage the chromophore activity of cytochrome c oxidase, an electron transport chain complex that efficiently absorbs this light. This absorption triggers various downstream effects in mitochondria, mitigating local oxidative stress by maintaining mitochondrial membrane potential and curbing overproduction of reactive oxygen species by dysfunctional mitochondria. By regulating apoptotic pathways, PBM boosts cell survival and is demonstrated to decrease microglial activation post-TBI, enhancing local anti-inflammatory effects.

Research Findings: The Positive Impact of Near-Infrared Light on Brain Function Recovery

Led by Professor Zubair Ahmed, Professor Will Palin, Dr. Mohammed Hadis, and surgeons Mr. Andrew Stevens and Mr. David Davies, the Birmingham research team examined the recovery effects of two light wavelengths (660nm red and 810nm near-infrared) following injury.

Conducted on animal models, the study involved daily two-minute infrared light treatments for three days after injury.

Results indicated a notable reduction in astrocyte and microglia activity, key players in post-head trauma brain inflammation, along with a significant drop in biochemical apoptosis markers.

After four weeks, functional tests for balance and cognition demonstrated marked improvements. Red light therapy hastened recovery compared to the control group, yet the 810nm near-infrared light proved superior.

Research Conclusion

This study offers compelling evidence for the efficacy of PBM in mTBI recovery. Notably, 810nm near-infrared light emerges as the most effective wavelength for enhancing recovery. The research further uncovers how PBM mitigates damage and fosters repair post-neurotrauma. PBM stands as a potential therapy post-neurotrauma, providing neuroprotection and aiding in the recovery of lost functions.

Reference：

Andrew R. Stevens, Mohammed Hadis, Abhinav Thareja, Freya G. Anderson, Michael R. Milward, Valentina Di Pietro, Antonio Belli, William Palin, David J. Davies, Zubair Ahmed,Photobiomodulation improves functional recovery after mild traumatic brain injury,Bioengineering & Translational Medicine