Light Therapy Device Tested Against Long COVID Brain Fog in Remote RCT
A double-blind trial tests whether 810nm photobiomodulation can reverse cognitive impairment in long COVID patients at home.
Summary
Long COVID has left millions struggling with brain fog, memory problems, and cognitive decline months or years after infection. This completed Phase 1 trial tested whether the Vielight Neuro RX Gamma — a wearable device delivering near-infrared light at 810nm, pulsed at 40 Hz — could improve cognition in 36 adults with confirmed post-COVID cognitive impairment. The fully remote, double-blind, randomized controlled trial assigned participants to either an active or sham device for 120 days, tracking symptoms daily. The science behind photobiomodulation suggests that NIR light stimulates mitochondrial activity, reduces neuroinflammation, and activates M2 microglia that clear amyloid and potentially other inflammatory debris associated with brain fog.
Detailed Summary
Long COVID affects an estimated 10–30% of people infected with SARS-CoV-2, with brain fog among the most debilitating and persistent symptoms. Cognitive impairment in this population lacks proven treatments, making any intervention trial a meaningful contribution to an urgent unmet need.
This completed Phase 1 randomized controlled trial enrolled 36 adults with confirmed post-COVID cognitive impairment. Half were assigned the active Vielight Neuro RX Gamma device — a portable, home-use unit delivering near-infrared (NIR) light at 810nm, pulsed at 40 Hz to the brain and nasal cavity — while the other half received a sham device. The fully remote, virtual design allowed participation without clinic visits, increasing accessibility and real-world relevance.
The mechanistic rationale is grounded in photobiomodulation (PBM) science: NIR light is absorbed by cytochrome c oxidase in mitochondria, boosting cellular energy production, reducing oxidative stress, and modulating inflammatory pathways. Pulsing at 40 Hz specifically targets gamma oscillations implicated in cognitive function and activates M2-phenotype microglia, which clear amyloid beta and potentially neuroinflammatory debris linked to long COVID pathology.
The trial ran from April 2023 to January 2025. Results are not yet published, but the completed status signals that data collection is finished. If the active device outperforms sham, this would represent a non-invasive, home-deployable intervention for a condition with no approved treatments. The 40 Hz PBM mechanism also overlaps with active Alzheimer's research, broadening the potential implications.
Key caveats include the small sample size of 36 participants, sponsor funding by Vielight Inc. introducing potential bias, Phase 1 status limiting generalizability, and the fact that this summary is based on the abstract only — no outcome data are currently available for evaluation.
Key Findings
- 36 long COVID patients randomized to active vs. sham 810nm NIR photobiomodulation for 120 days.
- Device pulses at 40 Hz, targeting gamma oscillations and M2 microglial activation linked to cognitive clearing.
- Fully remote trial design enables home-based delivery with no clinic visits required.
- Trial is completed as of January 2025; outcome data not yet publicly available.
- PBM mechanism targets mitochondrial function and neuroinflammation implicated in both long COVID and Alzheimer's.
Methodology
Double-blind, randomized controlled trial with 36 participants split equally between active and sham Vielight Neuro RX Gamma devices. Conducted entirely remotely over 120 days with daily symptom tracking via survey. Phase 1 designation reflects early-stage safety and feasibility focus.
Study Limitations
This summary is based on the abstract only, as the full trial results have not yet been published. The sample size of 36 is small, limiting statistical power and generalizability. Sponsor funding by Vielight Inc. introduces potential conflict of interest that warrants cautious interpretation of future results.
Enjoyed this summary?
Get the latest longevity research delivered to your inbox every week.