More than 55 million people worldwide are living with Alzheimer’s disease, with estimates suggesting that this number will only grow as people continue to live longer. Over 95% of these cases are diagnosed as late-stage Alzheimer’s and often cannot be attributed to heritable genes, making this prevalent neurological disease very difficult to treat.
Now, Cognito Therapeutics, a neurotechnology company birthed out of MIT, is pioneering breakthrough technology that may be able to slow the progression of Alzheimer’s and restore cognition. Using a 40 Hz light-flickering and auditory headset they have named “GENUS” (Gamma Entrainment Using Sensory stimuli), a recent pilot clinical trial found that this technology is not only safe and tolerable for home use but also has a positive impact on reducing symptoms associated with age-related neurodegeneration.
In the first phase of this pilot study, participants underwent one session of GENUS sensory stimulation during which they wore an EEG cap to record brain activity. The stimulation consisted of synchronized flickering light and high-frequency sound. To determine whether this stimulation was tolerable across different ages, investigators recruited three different cohorts: (1) adults aged 18 – 35 years with normal cognition, (2) adults aged 50-100 years with normal cognition, and (3) adults aged 50 – 100 years with mild dementia linked to a suspected Alzheimer’s diagnosis. Two additional patients with epilepsy were recruited to confirm that the flickering lights would not generate adverse effects.
Not only was this technology well tolerated, but Chan et. al also found that GENUS stimulation enhanced neural activity across multiple brain regions, including parts of the hippocampus that are critical for learning and memory. Interestingly, the benefits of this stimulation were distributed differently across the three cohorts. Regardless of age, those who were cognitively normal exhibited an increase in neural activity throughout the brain. In contrast, enhanced activity was concentrated in the frontal regions among individuals with Alzheimer’s dementia. Investigators speculate that this difference may reflect disease-related neural changes in Alzheimer’s that may be a potential biomarker for diagnosis.
If one session of GENUS stimulation can enhance neural activity, perhaps daily stimulation may generate long-term benefits for those with Alzheimer’s disease. To test this hypothesis, Chan et. al enrolled a subgroup of participants with early symptoms of Alzheimer’s disease from the initial cohort into the second phase of this study. A total of 15 participants were blinded and randomized into either an active GENUS-stimulated group or a control group that experienced white noise and constant light stimulation. Prior to the study, each participant underwent baseline cognitive assessments and brain MRIs. They were then sent home with a wearable GENUS headset and instructed to use it every day for an hour for six months. To ensure compliance, the stimulation devices were fashioned with a built-in time stamp log that tracked how long the device was on.
After 3 months, the participants returned to the lab for reassessments. Compared to the control group, the active stimulation group exhibited less brain atrophy, improved sleep, and enhanced performance on face-name association memory tasks. The GENUS stimulation devices seemed to be having a positive impact on disease progression. However, due to disruption from the COVID-19 pandemic, participants were unable to return for reassessments at the end of the 6-month study. Regardless, promising results from their final 4-month check-in suggested that the stimulation effectively slowed neurodegeneration.
Combining light and auditory sensory inputs, GENUS stimulation seems to not only improve cognitive performance but also induce structural changes in the brain that make the brain resilient to atrophy. How this technology works, however, is not yet clear. Early studies in mice suggested that 40Hz light and auditory stimulation may counteract reduced age-related changes in neural activity by influencing how neurons communicate.
Cognito Therapeutics is still conducting several ongoing clinical trials into the safety and efficacy of audiovisual stimulation for treating Alzheimer’s and other neurocognitive conditions. Promising results from recent Phase 3 clinical trials have already led to FDA Breakthrough Device recognition, suggesting that these stimulation devices may be ready for approval by 2025. Designed to be self-administered and personalized to each individual, GENUS may be a cheaper, more accessible treatment option to pharmaceutical interventions. If wearing this headset for an hour a day can slow the progression of age-related neurodegeneration as much as or perhaps better than a drug, this is technology that could help tens of millions of people around the world.