Case in point....dementia - Alzheimer's and related mental health diseases are genetic based diseases. Research is looking at all of the various conduits that may or may not contribute, add to or be party to this disease. By chance on one of the studies a few years back, it was noticed that those subjects (counted people - double blind) being studied, a common factor stood out. This factor was that most of these people were hard of hearing or had some degree of hearing loss. The researchers were blind-sided by this fact since they were not even looking for any common threads between the people but what was going on in their brain. This opened up a lot of eyes to the fact that that the elephant was actually sitting in the room with them. They just didn't see it with their magnifying scope or petri dishes. Those who were interested - posed questions of what actually happens to the brain/inner ear/ when it is not stimulated with sound and processing it to actually looking for answers that we find ourselves where we are today.
There are many frontiers about the brain that are not yet discovered including how to stop hearing loss, what is tinnitus, where is tinnitus located and how can we stop it, and a bounty of other complex questions that are yet to be defined and answered.
The many institutions and bodies of foundations that are pouring research into this field of study are putting out their ideas/thoughts to tell us what they know right now. But understand, our brain is so much more than all of the computers in the world. Think about what it can do and how it does it. Taking care of it requires a lot of work since our senses, our cognition, and our being are all caught up in this one organ.

I know why I have the first stage of organic brain syndrome. I was born without hearing much. Nothing was done about it....because no one knew. No testing was done until I was 50 years old. By that time, my brain was atrophied and had had experienced many assaults (3 MVAs, sepsis, Viral meningitis, etc). By the time I was diagnosed and given hearing aids, my brain didn't know how to respond and revolted. Migraine headaches were the mild responses as were the ongoing vertigo, hypercus, aneurysms, and other related brain symptoms. Management of the years has taken me through times to denial, hate, lashing out, withdrawal, anxiety, reaching out, education, advocacy, multiple tests, neuroscience specialists, audiologist, support groups, and other sources of information that have allowed me to grow and understand. My father also shared the DX of dementia when he died 5 years ago from prostate CA. A WWII vet - he was in the Pacific and was exposed to Hiroshima and Nagasaki - so carried that all his life. A sad ending to his life of 88 years. My life is not like his. Mine is because I was never given the opportunity to hear from the beginning of life. I didn't understand speech - it was mostly a silent world for me - and I was always wondering why.