Monday, July 19, 2021

Helping the Mute to Speak


Losing the ability to speak is tragic, especially if one's mind is otherwise intact.  Various diseases from encephalitis to stroke to ALS (amyotrophic lateral sclerosis, also known as Lou Gehrig's disease) can destroy the human speech system.  As long as some motor ability is left, victims can communicate by pointing to a sequence of letters on a board or by similar tedious means, but sometimes even that is no longer possible if the disease progresses.  Brain researchers have long sought a way to use the neural impulses in the brain's speech area to actuate an external "speech neuroprosthetic"—a machine that interprets the brain's impulses as speech.  And now, Dr. Edward Chang of the University of California San Francisco and his colleagues have done it.


Fifteen years ago, the patient they worked with (now in his 30s) suffered a severe brain-stem stroke that left him mostly paralyzed and unable to speak.  He has communicated since then by moving his head so that a pointer attached to a cap indicates letters on a board.  After extensive experimentation with epileptic surgery patients to determine which regions of the brain carried the most significant signals pertaining to speech, Chang implanted electrodes in the mute patient's brain and connected them to some sophisticated signal-processing systems, which probably involved trainable artificial-intelligence programs.  Then they asked the man to try saying specific sentences and noted the resulting signal patterns.  Eventually, the system was able to recognize these patterns when the man merely thought them with the intention of speaking.  A phrase or sentence takes a few seconds to appear after the patient forms it, but that is already faster than pointing to letters on a board.  Chang says there are many improvements to be made, but the demonstration shows that at least in one case, a speech neuroprosthesis can work.


This is a truly remarkable achievement, and in a blog usually devoted to bad news of one kind or another I thought it would be nice to look at something positive for a change.  At the same time, this feat raises all kinds of questions that medical advances raise.  How much would it cost if such a system is commercialized?  How safe is it to go around with wires implanted in your brain?  (Probably not very.)  Is there a less invasive means of detecting the brain impulses than wires directly on the brain?  Who gets to decide which of the thousands of mute people whose disability came about after they learned to talk, will get a chance to use it? 


Possibly some lessons can be learned from the analogous, but not quite so invasive, practice of cochlear implantation to remedy profound deafness.  The Wikipedia article on cochlear implants says that as of 2016, about 600,000 people worldwide have received them.  The average cost for the surgery in the U. S. is about $100,000, but if it works (and most of the time it does), society saves a substantial fraction of that cost because expensive special education is no longer needed for the patient.  The first cochlear implants were performed in the 1970s, so the procedure can said to be fairly routine by now.


Given the more invasive nature of the speech neuroprosthesis developed in San Francisco, we can suppose the procedure will cost more than a cochlear implant.  But years of development work lie ahead, and there may be issues or complications that arise along the way.  Let's suppose that the R&D goes smoothly and in another decade we have commercial speech neuroprostheses available.  Will that be a net benefit to the patients and to society?


This is just a specific example of the judgment called for when any society chooses to allocate scarce resources such as medical care.  One factor the U. S. apparently has going for it in comparison with many other countries is that there are strong financial incentives for companies to spend what it takes to develop advanced new medical products and procedures.  The free market has its downsides, certainly, but the semi-private nature of the way healthcare is paid for in the U. S., although deeply flawed, does have this redeeming feature. 


On the other hand, it's likely that not everyone who could benefit from a speech neuroprosthetic will get one.  Some people simply lived and died too early to benefit, but that doesn't mean they inevitably passed their lives in frustration and meaningless existence. 


When I taught in Massachusetts I would often have lunch at the student center in the central hotel complex at the University of Massachusetts Amherst, and quite a few times there I saw a married couple, Ruth Sienckiewicz-Mercer and Norman Mercer.  They were easy to spot because they were both shorter than four feet, wheelchair-bound, and Ruth was completely unable to talk. 


When she was less than a year old, she contracted encephalitis which left her with cerebral palsy that severely impaired her control of her body except for her face and digestive system.

Her family raised her until she was eleven, when financial difficulties led them to send her to the Belchertown State School, a warehousing facility for such hopeless cases.  She was mistreated as an idiot for years, but finally a sympathetic staff person developed a word board for her.  She became one of the high-functioning residents and was eventually able to move to her own apartment and marry another ex-patient of the school, Norman Mercer.  She then became a disability-rights activist, traveling across America and influencing governments to close warehousing institutions such as the State School, which eventually closed in 1992.  With the help of a co-author, she wrote a book about her experiences before she passed away in 1998.


Ruth Sienciewicz-Mercer didn't need a speech neuroprosthesis to do what she did.  Her indomitable spirit and the help of sympathetic bystanders enabled a supposedly disabled person to achieve things that most normally-abled people don't do.  If you believe that Y'shua the Nazarene was able to make the dumb speak by simply telling them to, he made it clear that the healings were not the main point of what he came to do either.  They helped the sufferers who came to be healed, certainly.  But they were only means to an end.  The end itself, the point of it all, was the relationship created between the Healer and the healed.  And that is a lesson we shouldn't forget.


Sources:  I thank my wife for pointing out to me the article in The Guardian entitled "Paralyzed man’s brain waves turned into sentences on computer in medical first" at  I also referred to the Wikipedia articles on cochlear implants and Ruth Sienciewicz-Mercer.  Her book, I Raise My Eyes to Say Yes, was co-authored with Steven Kaplan and published in 1996.

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