Phototherapy and photobiomodulation can improve cognitive function in dementia

Decline in cognitive function in dementia improved significantly with phototherapy (light therapy).

Phototherapy, therapeutic exposure to light, is an effective, safe, noninvasive way to boost cognition in dementia; making it a desirable option compared to drug treatments with adverse effects and limited efficacy.

A review, Phototherapy improves cognitive function in dementia: A systematic review and meta-analysis, just published in the journal Brain and Behavior examined a variety of therapeutic light applications for measurable improvements in cognition.

“This study aimed to investigate the effectiveness of phototherapy intervention on cognitive function in older adult patients with dementia. PubMed, Ovid MEDLINE, Web of Science, EMBASE, Cochrane Central Registry of Controlled Trials, PsycINFO, and Clinical Trials were searched from their inception to August 10, 2022, for randomized controlled trials involving patients with dementia who received phototherapy interventions. We used the weighted mean difference (MD) or standard weighted mean difference to generate the pooled estimates. The primary outcome was cognitive function as measured by the Mini-Mental State Examination (MMSE) score.”

The authors included studies on elderly adults with dementia, including Alzheimer's disease (AD), vascular dementia (VD), dementia with Lewy bodies (DLB), Parkinson's disease with dementia (PDD), mixed dementia (MD), or dementia due to other causes who had phototherapy interventions to controls that received no intervention but only routine care or health education.

There is a great need for safe and effective interventions…

“As drug treatment for dementia has limitations such as medical contraindications, limited efficacy, and adverse effects (Azhar et al., 2022; Wong, 2016), non-pharmacological therapy has been increasingly regarded as a critical part of comprehensive dementia care (Li et al., 2021; Sink et al., 2005). Phototherapy, which utilizes full-spectrum bright light usually above 600 lux (Onega et al., 2016; Zou et al., 2022) or wavelength-specific lights, such as blue-enriched (Cremascoli et al., 2021) or blue-green (Nowak, 2008) lights, is a promising non-pharmacological therapy that has the advantages of non-invasiveness, inexpensive, and high safety (Forbes et al., 2014; C.-R. Liu et al., 2021; Scales et al., 2018).”

A variety of interventions showed efficacy

Even though a third of the subjects had intermediate or high-risk disease at diagnosis, the great majority did well:

“Phototherapy interventions of all forms, frequencies, and durations were included in this review. In most (eight of 12) studies (Burns et al., 2009; Dowling et al., 2007; Figueir, 2019; Fontana Gasio et al., 2003; Graf et al., 2001; McCurry et al., 2011; Onega et al., 2016; Zou et al., 2022), phototherapy intervention was implemented using bright light, while two (Kolberg et al., 2021; Nizamutdinov et al., 2021) studies used LED light, and the remaining two (Cremascoli et al., 2021) used blue or blue-green light. Phototherapy duration generally ranged from 6 to 120 min. Half (six of 12) of the studies implemented phototherapy interventions at specific times of day, three (Burns et al., 2009; Nowak, 2008; Zou et al., 2022) in the morning, one (Graf et al., 2001) in the afternoon, one in (Fontana Gasio et al., 2003) the dawn-dusk period, and one (Dowling et al., 2007) consisting of two intervention groups in the morning and afternoon. Besides, four studies (Cremascoli et al., 2021; McCurry et al., 2011; Nizamutdinov et al., 2021; Onega et al., 2016) did not report a specific intervention time, and two (Figueir, 2019; Kolberg et al., 2021) utilized a 24-h lighting sequence. The frequency ranged from twice a day to five times per week, while most (nine of 12) studies used phototherapy once a day.”

A light box is the most commonly used modality:

“The light box was the most classic and commonly used device in phototherapy, and it provides full-spectrum bright light usually over 2500 lux, with a duration of at least 30 min in the daytime, lasting 4–8 weeks (Fetveit et al., 2003; Graf et al., 2001; C.-R. Liu et al., 2021; McCurry et al., 2011; Onega et al., 2016; Zou et al., 2022). It should be noted that the light box was placed 60 cm away from the patient at or above the patient's eye level…In recent years, helmets and glasses have also been used as phototherapy devices, which usually employ light of a specific wavelength with a duration of approximately 15 min (Cremascoli et al., 2021; Nizamutdinov et al., 2021). Such portable devices allow for better control of light intensity and are ergonomic without interfering with patients’ normal activities.”

In summary, the authors conclude:

“Our systematic review and meta-analysis suggests that phototherapy is a promising intervention, as it can improve cognitive function in older patients with dementia…further well-designed studies are needed to explore the most effective clinical implementation conditions, including device type, duration, frequency, and time.”

Keeping Aging Brains Healthy

Keeping Aging Brains Healthy - Battling Alzheimer’s Disease with Light and Sound, researchers at MIT’s Aging Brain Initiative are demonstrating how non-invasive modalities can support brain biology to protect and promote cognitive health.

“The Aging Brain Initiative is an interdisciplinary effort combining faculty expertise, knowledge, and technical resources from across MIT to solve the mysteries of the aging brain. MIT scientists are opening doors to an entirely new direction of brain research, building new tools to address the challenges of brain aging, and creating a better future for millions..”

Retraining the brain with sensory stimulation

MIT neuroscientists in the lab of Professor Li-Huei Tsai at The Picower Institute for Learning and Memory are studying how retraining brainwaves with lights flickering at appropriate wavelengths can reverse the effects of Alzheimer's and other diseases on the aging brain. Brain wave entrainment with gamma frequencies appears particularly helpful for reducing Alzheimer's disease pathology and improving memory.

“A growing body of evidence, including Aging Brain Director Li-Huei Tsai’s findings, hint at a meaningful connection between modulating brainwaves and affecting neurological disorders such as Alzheimer’s and Parkinson’s diseases. The work offers the possibility of forestalling or even reversing the damage caused by such conditions without using a drug."

“With 40-hertz light therapy, Alzheimer’s patients may one day be able to treat themselves—perhaps wearing a special headset that emits the flickering light. Here, we see a slice of a mouse brain exposed to light therapy causing a reversal of severe neurodegeneration.”

Brain Photobiomodulation (PBM)

Brain photobiomodulation can be applied with low level laser therapy (LLLT) and LED light sources. Devices worthy of consideration that use potent LEDs at specific wavelengths and frequencies to promote healthy brain biology include the Auragen™ Light & Sound System and the Neuronic Neuroradiant 1070.

Cognitive Optimization with Gamma Light and Sound Therapy - Auragen

40Hz Synchronized Gamma
Optimal Visual and Auditory Delivery

The Neuronic Neuradiant 1070 for transcranial
photobiomodulation therapy.