Groundbreaking TBI study by the U of Utah with the Vielight Neuro [Publication Summary]

Approximately 3.8 million sports- and recreation-related concussions occur annually in the United States, with growing concerns about their long-term effects on concentration and physical skills. Repetitive head impacts (RHIs), or repetitive head acceleration events (RHAEs), can lead to traumatic encephalopathy syndrome (TES) and chronic traumatic encephalopathy (CTE), even if they do not cause immediate symptoms. Athletes may experience over 100 RHAEs per season, resulting in microstructural and functional brain changes similar to concussions, impacting motor skills and neuromuscular health.

Brain photobiomodulation (PBM) with the Vielight Neuro Gamma was explored as a therapy for brain injuries by neurology professors from the University of Utah because of the patented simultaneous intranasal and transcranial PBM (itPBM). Brain PBM involves using light-emitting diodes (LEDs) to target brain regions with near-infrared light, promoting energy production, blood flow, and cell survival while reducing inflammation. This therapy may also enhance neuromuscular health by improving reaction time, dexterity, grip strength, and balance.

This study enrolled 49 participants (43 completed) aged 18-69 years, all with self-reported mTBI or RHAEs from sports or other activities. The study aimed to examine the effects of itPBM on neuromuscular health and found potential benefits, suggesting that PBM might improve or preserve physical performance and neuromuscular function.

Full study link

Figure 1 - Participant Background - U of Utah TBI PBM Study

Figure 1 – Participants Backgrounds (n=43)

Study Design

This study was a nonrandomized proof-of-concept design focusing on active treatment only. Participants were assessed before and 8-10 weeks after starting at-home itPBM treatments. They were instructed to maintain their normal routines and avoid new activities such as resistance or brain training.

Treatment Protocol

Participants self-administered itPBM using the Vielight Neuro Gamma PBM headset, which has four LEDs emitting NIR light (810 nm) and an intranasal probe emitting pulsed NIR light. Treatments lasted 20 minutes every other day for 8 weeks, with participants tracking usage on a log sheet.

Figure 2 – Placement of the Vielight Neuro Gamma over the Default Mode Network and intranasal

Figure 3 – PBM Parameters of the Vielight Neuro device

Clinical Performance Tests

Four assessments were conducted alongside cognitive and neuropsychological tests and a brain MRI:

  • Clinical Reaction Time
    Participants caught a falling stick with their dominant hand to measure reaction time, calculated using the distance the stick dropped and the formula for a body falling under gravity.
  • Grooved Pegboard Test
    Manipulative dexterity was assessed using a metal board with 25 keyhole-shaped slots. Participants inserted pegs into the holes as quickly as possible, recording the time taken to complete the task with each hand.
  • Grip Strength
    Measured using a Jamar Plus Dynamometer, participants squeezed the handle as hard as possible for 3 seconds, with three trials per hand. The average force was recorded.
  • Mini Balance Evaluation Systems Test (MiniBEST)
    This test assessed 14 tasks across four domains (anticipatory postural adjustments, reactive postural control, sensory orientation, and dynamic gait), scoring each task on a three-level ordinal scale with a maximum total score of 28. The overall score and individual subscores for each domain were recorded.

Figure 4 – Summary Statistics of the Motor Assessments

Statistical Analysis

Motor tests were scored according to their standards. Data from participants with limb injuries were excluded. Normality of measurements was evaluated using Shapiro-Wilk tests. Linear mixed-effect analyses, using the maximum likelihood method, assessed motor outcomes with “age” and “visit time” as fixed effects and random intercepts by “participant.” Normality was confirmed through residuals examination. Wilcoxon’s signed-rank test was used for non-normal variables. The Benjamini-Hochberg procedure controlled for multiple comparisons, with a significance threshold of α = 0.05. P values with 95% confidence intervals (CIs) were reported, and effect size was measured by Hedges’ g.

Figure 5 – Mixed Effects of Vielight Neuro PBM on TBI


Due to travel or personal conflicts, some participants extended their treatment to 10-12 weeks, maintaining a 92% compliance rate. Pre- and post-treatment results showed significant improvements in three of four test domains:

  • Reaction time improved by 19.39 ms (p < 0.001) with an effect size of 0.75.
  • Dominant-hand grip strength increased by 2.70 kg (p = 0.003) and nondominant hand by 3.73 kg (p < 0.001), with small effect sizes.
  • Overall MiniBEST scores improved by 1.32 points (p < 0.001) with a moderate effect size.

Although statistically significant, some improvements were near or below clinically significant thresholds. However, 23% of participants improved MiniBEST scores by three or more points. Longer interventions may demonstrate greater improvements, considering the low-risk, ease of use, and low cost of itPBM.


This study suggests that itPBM has small to moderate effects on grip strength, balance, and reaction time in individuals with chronic RHAE symptoms. Future research should investigate how PBM applied to the head affects distal neuromuscular systems and include more robust designs to validate these findings.


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