Toronto, Ontario, Jan. 14, 2026 (GLOBE NEWSWIRE) -- Toronto, Canada — January 14, 2026
A new randomized, double-blind, sham-controlled clinical trial reports that a non-invasive, home-based light therapy produced measurable improvements in objective cognitive performance in adults under 45 with long COVID-related brain fog. This is often a disabling condition that continues to limit workforce participation, strain healthcare systems, and undermine mental well-being worldwide.
Cognitive dysfunction, often referred to as “brain fog,” is one of the most persistent and debilitating symptoms of post-COVID-19 condition (PCC). It interferes with attention, memory, and executive function, limiting the ability of affected individuals, many of them of working age, to return to work, education, and daily responsibilities. Beyond the personal toll, long COVID brain fog contributes to reduced workforce participation, increased healthcare utilization, and rising mental-health burden, creating ripple effects across the broader economy and society.
The study, published today in The Lancet’s eClinicalMedicine, evaluated intranasal and transcranial photobiomodulation (itPBM), a form of near-infrared light stimulation designed to support brain metabolism and network function. The intervention was delivered using the Vielight Neuro RX Gamma, a itPBM device configured for this clinical trial. The trial represents one of the most rigorously controlled investigations to date of a scalable, home-use intervention targeting cognitive dysfunction associated with long COVID.
Addressing a Major Unmet Need
Despite affecting millions globally, there are currently no established, evidence-based treatments specifically approved for PCC-related cognitive impairment. Many patients report being left without therapeutic options, relying instead on symptom management and coping strategies.
“This is a major unmet medical and societal need,” said Dr. Lew Lim, corresponding author of the study and founder of Vielight Inc. “Long COVID brain fog doesn’t just affect individuals. It impacts families, employers, healthcare systems, and mental well-being. Our objective was to rigorously evaluate whether a non-invasive, home-based intervention could produce objective signals of cognitive improvement, particularly in people still early in their working lives.”
Study Design and Key Findings
The U.S.-based pilot trial enrolled 43 adults aged 18-65 with persistent cognitive symptoms at least 12 weeks following COVID-19 infection. Participants were randomized to receive either active itPBM or a visually identical sham intervention for eight weeks, with participants, investigators, and outcome assessors blinded to treatment allocation.
Unlike many long COVID studies that rely primarily on self-reported symptoms, the primary endpoint was objective cognitive performance, assessed using a validated digital cognitive battery measuring attention, memory, and executive function.
Key findings included:
- Participants under 45 years of age receiving active itPBM showed statistically significant improvements in composite cognitive performance compared with sham.
- Tasks related to attention demonstrated consistent signals of improvement across multiple timepoints.
- The intervention was well tolerated, with no serious adverse events, and adherence to unsupervised home use was high.
- In the full study population, participants receiving active treatment showed greater improvement than sham at the primary endpoint, although the overall between-group difference did not reach conventional statistical significance.
- Secondary outcomes, including fatigue and quality-of-life measures, showed mixed results, reflecting the heterogeneity of long COVID.
Scientific Perspective
“From a neuroscience perspective, this study stands out for its rigorous sham-controlled design and use of objective cognitive endpoints,” said Dr. Reza Zomorrodi, neuroscientist and senior author affiliated with the Centre for Addiction and Mental Health (CAMH) and the University of Toronto. “While the findings are preliminary, the improvements observed, particularly in attention, are consistent with known mechanisms of network-level modulation and neuroplasticity. These results support further investigation in larger trials to clarify who benefits most and why.”
Looking Ahead
The authors stress that further research is required to confirm and extend these findings. Planned next steps include:
- Evaluation of different dosing strategies and treatment durations, particularly in older adults
- Integration of neurophysiological and inflammatory biomarkers to better understand mechanisms and responders
- Assessment of the durability of cognitive changes over longer follow-up periods
- Expansion into larger randomized trials to validate and extend these findings across broader populations
“Long COVID is a complex and heterogeneous condition,” Dr. Lim added. “No single intervention will work for everyone. People with long COVID brain fog are trying to get their lives back - back to work, back to thinking clearly, back to functioning. What this study shows is that a simple, home-based brain intervention can produce objective signals of improvement, and that is something worth paying attention to.”
About the Study
The study, “Photobiomodulation for Cognitive Dysfunction (Brain Fog) in Post-COVID-19 Condition: A Randomized Double-Blind Sham-Controlled Pilot Trial,” was registered at ClinicalTrials.gov (NCT05857124) and conducted in accordance with ethical and regulatory guidelines. The study was funded by Vielight Inc.
About Vielight Inc.
Vielight Inc. is a Toronto-based medical device research and technology company developing non-invasive photobiomodulation systems for use in clinical research and regulated healthcare settings. Vielight devices have been used in investigator-led studies exploring neurological, cognitive, and systemic conditions.
Forward-Looking Statements
This press release reports findings from a randomized, double-blind, sham-controlled clinical trial evaluating a non-invasive, home-based intervention for long COVID–related cognitive dysfunction. While further studies are planned to validate and extend these results, the findings provide a scientifically credible signal of benefit in a condition for which no established treatments currently exist. No clinical claims are made regarding diagnosis, treatment, or cure.
Attachments
- Vielight Neuro RX Gamma device and irradiation configuration used in the randomized, double-blind, sham-controlled trial.
- Primary endpoint at Day 56 (Active–Sham), stratified by age group.
Peter Adams Vielight Inc. 1-416-710-7140 peteradams@vielight.com