Controlled Studies of Brain Photobiomodulation

Improved bioenergetics and brain health can be achieved non-invasively with red-to-near-infrared light stimulation in a process called photobiomodulation (PBM). Photons in this wavelength range of light from lasers or LEDs have been used for brain PBM of important brain bioenergetics processes, such as up-regulation of the mitochondrial respiratory enzyme cytochrome c oxidase, improved oxygen consumption and hemodynamic oxygenation of the brain, as well as for several brain health applications in psychology, psychiatry and neurology. Transcranial PBM is a promising technique that delivers red-to-near-infrared photons to the head to stimulate brain bioenergetic mechanisms based on promotion of mitochondrial oxidative energy metabolism and cerebral hemodynamics. Photons in this spectral range are able to penetrate the scalp/skull/meninges and the brain in rodent animal models and to reach inside the human cerebral cortex, where they have been demonstrated in vivo to photo-oxidize cytochrome c oxidase, release nitric oxide and trigger a hemodynamic response of oxygenated hemoglobin. Today, the brain health applications of PBM are very diverse, but its use as a light-based therapeutic technique in healthcare has not gained substantial credibility among the available therapeutic modalities. The available literature supports that brain PBM is a promising therapeutic approach that deserves rigorous study because it can modulate important bioenergetics processes in a way that is safe, pain-free, inexpensive, easy to apply, and well-tolerated by individuals. However, many studies in the PBM field lack scientific rigor for the claims they made due to limited controls, inadequate experimental design or analysis, and incomplete description of PBM parameters. For the field of brain PBM to move forward there is an urgent need for well-controlled studies with more scientific rigor and methodological details that will allow consistent replication. The objective of this special issue is to address this need for scientific rigor by publishing well-controlled studies with uniform sections providing detailed: 1) adequate experimental design and controls, 2) a table listing the complete PBM parameters, 3) proper statistical analysis including objective outcome measures, and 4) including a limitations section that delineates the pitfalls and specific needs for further research. In this respect, the Guest Editors encourage the submission of new contributions on neuroscience topics of brain PBM. The following items are required criteria for this special issue:
• With respect to original research works, well-controlled randomized clinical trials and in vivo animal studies are welcome for submission for peer-review.
• Article types of review papers and opinions or perspectives are also welcome for submission.
• Uncontrolled studies, case reports and case series studies as well as in vitro studies are not accepted.
• In the materials and methods section of original studies, all manuscripts should include 1) a detailed experimental design with a timeline diagram of the experiments and 2) a table with all the PBM treatment parameters, and 3) statistical analysis clearly described with objective outcome measures to establish scientific validity.
• All original research articles should include a section of “Study Limitations” in the Discussion.

Prof Paolo Cassano is co-founder, share-holder, board member and chair of SAB of Niraxx Light Therapeutics Inc. He filed patents in the field of PBM for brain disorders; however, none has been issued.