First Human Trials Test Light and Sound Therapy For Alzheimer's Disease

A new study published in the journal PLoS ONE has reported on the first human tests of an experimental therapy using sound and light to treat Alzheimer's disease (AD). New Atlas reports: Over the last seven years, Li-Huei Tsai and colleagues at MIT's Picower Institute for Learning and Memory have been investigating an unusual hypothesis. The researchers found toxic proteins associated with Alzheimer's disease could be eliminated from mouse brains following exposure to flickering lights. Further research found the magic frequency was 40 Hz. When animals were exposed to both sound and light at that frequency, improvements in brain health were detected. Of course, these kinds of animal tests don't mean much if they can't be replicated in humans, so after further investigations revealed how this sensory therapy could be affecting a mouse brain, the researchers started preliminary human experiments. Working with colleagues at Massachusetts General Hospital, two clinical trials set out to test the therapy in humans. The first Phase 1 study recruited 43 participants to test whether this kind of light and sound exposure was safe, and did anything to the human brain. Each subject was monitored using EEG measures while experiencing a short exposure to what has been dubbed by the researchers as GENUS (Gamma ENtrainment Using Sensory stimulation). This preliminary study comprised both healthy and cognitively impaired subjects, as well as participants with epilepsy in order to evaluate the seizure potential of the treatment. After a short exposure to the sensory stimulation, the researchers found a number of brain regions synchronize with the 40-Hz frequency. The second trial recruited 15 participants with early-stage Alzheimer's disease. Each participant was given a device to take home and use for around an hour a day. The device was essentially a small LED white board with an iPad in the middle and a soundbar underneath. While watching videos on the iPad, the LED light panel on the white board would flicker at a rate of 40 Hz and the soundbar would play a 40-Hz tone. Half the cohort was randomized to a sham control condition, exposed to a constant white light and white noise. Compliance was relatively high between both the GENUS and the sham groups, with participants completing the daily requirement of exposure around 90 percent of the time. After around three months of use the researchers could detect statistically significant differences between the two groups, both on brain imaging and memory tests. The researchers are cautious not to overstate their initial findings, the report says. "It's early days for human studies [...], larger cohorts of patients are needed to better understand the impacts of this sensory stimulation and longer trials will hopefully establish more prominent beneficial effects."

Read more of this story at Slashdot.