Pilot Study on Dose-Dependent Effects of Transcranial Photobiomodulation on Brain Electrical Oscillations: A Potential Therapeutic Target in Alzheimer's Disease.

BACKGROUND: Transcranial photobiomodulation (tPBM) has recently emerged as a potential cognitive enhancement technique and clinical treatment for various neuropsychiatric and neurodegenerative disorders by delivering invisible near-infrared light to the scalp and increasing energy metabolism in the brain. OBJECTIVE: We assessed whether transcranial photobiomodulation with near-infrared light modulates cerebral electrical activity through electroencephalogram (EEG) and cerebral blood flow (CBF). METHODS: We conducted a single-blind, sham-controlled pilot study to test the effect of continuous (c-tPBM), pulse (p-tPBM), and sham (s-tPBM) transcranial photobiomodulation on EEG oscillations and CBF using diffuse correlation spectroscopy (DCS) in a sample of ten healthy subjects [6F/4 M; mean age 28.6±12.9 years]. c-tPBM near-infrared radiation (NIR) (830 nm; 54.8 mW/cm2; 65.8 J/cm2; 2.3 kJ) and p-tPBM (830 nm; 10 Hz; 54.8 mW/cm2; 33%; 21.7 J/cm2; 0.8 kJ) were delivered concurrently to the frontal areas by four LED clusters. EEG and DCS recordings were performed weekly before, during, and after each tPBM session. RESULTS: c-tPBM significantly boosted gamma (t = 3.02, df = 7, p < 0.02) and beta (t = 2.91, df = 7, p < 0.03) EEG spectral powers in eyes-open recordings and gamma power (t = 3.61, df = 6, p < 0.015) in eyes-closed recordings, with a widespread increase over frontal-central scalp regions. There was no significant effect of tPBM on CBF compared to sham. CONCLUSION: Our data suggest a dose-dependent effect of tPBM with NIR on cerebral gamma and beta neuronal activity. Altogether, our findings support the neuromodulatory effect of transcranial NIR.

Treatment for anxiety: Mindfulness meditation versus escitalopram (TAME): Design of a randomized, controlled non-inferiority trial.

Anxiety disorders (generalized anxiety disorder, social anxiety disorder, panic disorder, and agoraphobia) are common, distressing, and impairing. While pharmacotherapy and psychotherapy are first-line treatment strategies for anxiety disorders, many patients are reluctant to take psychiatric medication, and many prefer to avoid any kind of mental health treatment due to stigma or distrust of traditional medical care. We present the trial protocol for the first study comparing first-line medication treatment with Mindfulness-Based Stress Reduction (MBSR), a popular mindfulness meditation training program, for the treatment of anxiety disorders. We will use a non-inferiority, comparative effectiveness trial design, in which individuals with diagnosed anxiety disorders will be randomized to either pharmacotherapy with escitalopram or MBSR for 8 weeks of treatment. Treatment outcome will be based on gold standard symptom severity measures assessed by trained independent evaluators blind to treatment allocation. Secondary outcomes will include key symptom and function measures, as well as tolerability and satisfaction with treatment. Findings will provide crucial information to inform decision making about the relative benefits of MBSR versus a first line medication for anxiety disorders by patients, medical care providers, healthcare insurers and other stakeholders.