Audio Visual Stimulation (AVS):
AVS is an older modality than neurofeedback, with research dating back at least to the 1940s. The idea is that by using flashing lights and pulsing sounds one is able to “entrain” the brain to certain frequencies. For many people, this clearly works and is obviously visible on real-time EEG readouts. It also has been shown to increase cerebral blood flow to the frontal cortex and other parts of the brain. It can be used as a stand-alone modality (it has been used and studied with ADHD, academic performance, depression and anxiety, with good results) or as a way to assist the brain in moving towards desired frequencies while also doing standard neurofeedback. It can also be coupled with EEG technology, wherein the brain’s own frequencies drive the entrainment process. This often seems to make the process more powerful and effective.
One recent study (link) conducted at MIT has received quite a bit of attention recently, and for good reason. It showed that using visual stimulation at a certain frequency with mice who have Alzheimer’s disease reduces beta amyloid plaques by 50%. The Dean of the MIT School of Science, Michael Sipser, was so excited he had this to say:
“This important announcement may herald a breakthrough in the understanding and treatment of Alzheimer’s disease, a terrible affliction affecting millions of people and their families around the world. Our MIT scientists have opened the door to an entirely new direction of research on this brain disorder and the mechanisms that may cause or prevent it. I find it extremely exciting.”
Of course this research is in its early stages, but it validates what many clinicians and researchers have know for quite some time: using targeted visual and audio stimulation can have powerful, and often very beneficial, effects.
This technology should not be used by anyone at risk for seizures, in particular those with photosensitive epilepsy (about 1 in 4,000 of people between 5 and 24 yrs./less common in older adults) as there is seizure risk for that population.