Toronto, Ontario — January 8, 2026 — Leads & Copy — A recent study by the Rotman Research Institute at Baycrest, University of Toronto, indicates that brief sessions of pulsed photobiomodulation (PBM) can significantly enhance cerebrospinal fluid (CSF) flow, which is crucial for the brain’s glymphatic waste-clearance system.
The glymphatic pathway is responsible for draining away waste metabolic products and soluble proteins like amyloid-beta. Its dysfunction is linked to neurodegenerative diseases such as Alzheimer’s and Parkinson’s. Dr. Jean Chen suggests that PBM could be a promising therapeutic tool against these diseases by improving CSF clearance and supporting healthy brain aging.
The glymphatic system, a network of CSF and interstitial fluid channels, acts as the brain’s waste clearance pathway. When glymphatic flow slows, neurotoxic proteins accumulate. Impairment of glymphatic drainage has been observed in Alzheimer’s and Parkinson’s models. Enhancing this clearance could offer protection, with PBM serving as a non-invasive neuroprotective strategy for maintaining effective brain waste clearance. Scientific consensus is growing that enhancing CSF flow may help counteract neurotoxic waste accumulation implicated in dementia, traumatic brain injury, and other chronic brain disorders.
The Baycrest team investigated whether PBM could directly modulate CSF dynamics in healthy adults. Using functional MRI, they found that just 4 minutes of low-level NIR light induced immediate changes in brain fluid movement. Key findings include:
A brief PBM session caused a surge in intracranial CSF volume and a corresponding drop in net CSF inflow. Both forehead and nostril-based PBM showed stronger CSF effects at higher irradiances, with a clear wavelength–irradiance interaction. Forehead PBM responses were melanin-dependent, with lighter-skinned subjects showing larger CSF increases than darker-skinned volunteers. Intranasal PBM produced the same CSF-modulating effect as forehead PBM using only a small fraction of the power.
The authors propose that PBM transiently raises intracranial pressure to push CSF out, increasing the transport of toxins and waste out of the brain. The intranasal approach sidesteps the melanin effect, making it more consistent across individuals.
Vielight’s devices use this nostril-based PBM. The company’s patented intranasal applicator places an 810 nm LED in each nostril, delivering NIR light directly to capillaries and the olfactory region. This approach offers high energy efficiency, exact dose control, melanin-independence, and targeted glymphatic access. Dr. Jean Chen notes that a single nasal LED can focus light onto the olfactory/glymphatic interface, something a standard helmet cannot do.
Dr. Lew Lim, Founder and CEO of Vielight, stated that the research validates the company’s patented intranasal technology, demonstrating superior optical efficiency and ensuring consistent dose regardless of hair density or skin tone.
Vielight’s Neuro Duo and Neuro Pro use 810 nm light, which the Baycrest findings support. Monte Carlo simulations have shown that 810 nm light deposits more energy in prefrontal cortical regions than 1064 nm under equivalent conditions. The choice of 810 nm is also supported by photobiology, aligning well with the absorption spectrum of cytochrome c oxidase.
The Baycrest study provides evidence that PBM can directly modulate brain fluid flow, with implications for neurology, sports medicine, and healthy aging.
Dominic Lim Vielight Inc. dominic@vielight.com
Source: Vielight
