Could BCI Allow ALS Patients Speak Again?

Irene Nguyen, 8/30/24

What is ALS? 

The abbreviation for ALS is Amyotrophic lateral sclerosis, a disease that affects the nervous system and causes the muscles of the body to become immobile and lose control. The disease itself causes the muscle to be unable to work properly, with needed functions like breathing, movement, speaking, and eating not being able to perform or carried out by the owner. ALS, a fatal disease, is not pervasive in society and only a small percentage of people inherit such lethal medical conditions. However, a baseball player by the name of Lou Gehrig was found to exhibit ALS which inhibited his career playing baseball. Some symptoms of ALS were found to be muscle twitching and weakness points in the arms and legs, difficulty swallowing intake, and slurred speech. Medical professionals have not been able to find a cure for ALS as of late. While ALS is rare in society, those being oppressed by the disease have not yet found solace as the affliction is said to be insidious and gets worse over time. 

What is the Brain-computer interface?

Brain-computer interface (BCI) other known as a brain-machine interface is a systematic way of explaining how an individual can possess control over a computer only by using their brainwaves, with no movement required. The ability to do everyday regular tasks can be a herculean task for those with severe medical conditions and those losing their mobility. Brain-computer interface allows individuals to enjoy the freedom of moving and facilitate maneuvering much easier. There are a myriad of functions that, by occupying the brain-computer interface, can be carried out if only the properties of such are virtual. For example, BCI can be implemented for communication purposes, computer access, control of mobility devices such as a wheelchair or a prosthetic arm, and other multifarious applications. BCI is a useful and apposite invention that helps with rehabilitation and facilitating the recoupment of motor skills that were lost due profound impact on the body or due to appalling health conditions. The reclamation of mobilities for patients has made a great impact on their everyday lives as well as making the quality of life much higher. 

There are two kinds of BCI, and each has its own advantages and disadvantages. 

• Invasive BCI System 

Surgery and implantment of this system are requisite for it to work. Electrodes are engrafted on the surface of the brain or near it. The conformity of the invasive BCI system is not exact and changes based on the sensitivity of patients. 

• Noninvasive BCI System 

No surgery is needed for the noninvasive BCI system. A cap with electrodes, usually one that looks like a fabric swimming cap, is placed on the person's head and connected to a rebooting machine in order for it to work. Noninvasive BCI systems are preferred since the motion apparatus is guaranteed to provide the individual with little to no comfort. 

Regardless of which type of BCI system, both of them are connected to an external hardware device or a computer that sends brainwaves, retained by the electrodes, and delivers them to the computer. Inside a methodology of programs and complex software are conducted to act as a translator for the brainwaves sent to the computer to perform commands. 

One Man's Story 

David Brandman, a UC Davis neurosurgeon, had a revolutionary idea to invent a system that can translate brainwaves into speech that now has a 97.5% accuracy rate. The main purpose of the brain-computer interface (BCI) is to serve those who have been diagnosed with ASL and have lost some mobility, which includes slurred speech, inability to walk, and other bodily movements. David Brandman and his team enrolled many participants in the BrainGate clinic to try his BCI in order to gain insight into areas of improvement and for research purposes. Trials were conducted to oversee which area needed amelioration, so the team enrolled Casey Harrell. 

Casey Harrell, an impaired man with ASL, was asked to help with the development of the BCI. Harrell was a 45-year-old man who suffered from ASL, at the time he had weakness in his arms and legs (tetraparesis) and inaudible speech (dysarthria), so there were assistants to help elucidate his words. David Branmand and the BrainGate clinical team started to get to work. David Brandman situated four microelectrode arrays on the region of the brain liable for coordinating speech (left precentral gyrus). The configuration of the arrays serves as a recording system that can document brain activities from 256 cortical electrodes. The neat, carefully constructed device is one of the main forms of ways Brandman used to deliver his patients' messages into human speech via a computer. The process is simple in practice but is complicated in the scientific sense. Firstly, the BrainGate clinical team was deliberate with the placement of the arrays, they carefully selected an area that was responsible for sending commands to the muscle and to listen attentively to that. The patterns of the brain are then converted into a phoneme, syllable or a unit of speech and audible voices can be heard from the person. However, a frequent problem that would arise was that word detection and communication were off and not accurate. 

David Brandmand said, “Previous speech BCI systems had frequent word errors. This made it difficult for the user to be understood consistently and was a barrier to communication.” The objective of his ingenuity invention was to allow people occupying the BCI to communicate with their loved ones in a consistent and easily comprehensible way, so failure to take notice of this would be detrimental. After much-solicited data and research from numerous trials, the BCI was able to successfully surpass its 50 vocabularies from the first run to 1225,000 words in the second run. In the first stage of things, the system took a punctual 30 minutes to reach 50 words and a 99.6% accuracy rate. After a myriad amount of trials later the system grew to produce a faster and wider range of words with a 97.5% accuracy rate! The BCI, without a doubt in mind, outshines any commercially available smartphone applications out there that can gloss a person’s tone of message. 

BCI is sincerely one of the most useful inventions as it is an emancipation process in which a person with ASL can regain their inherent ability to talk again and is now able to vocally deliver their thoughts. Chains and bindings that kept valetudinarians with ASL feeling trapped are now alleviating due to the technological advancements of BCI. Casey Harrell at the first speech data training section cried in tears of joy as to heard his voice again pre-ASL played out through the computer screen. “The first time we tried the system, he cried with joy as the words he was trying to say correctly appeared on-screen. We all did,” said Stavisky, one of BrainGate's Clinical researchers. The hysteria and overwhelming sense of joy that Casey Harrell as well as many others with similar circumstances will make even the most aloof individual crack a cheerful smile at the sight. Brain-computer interface, is an efficacious device that wields the power to make an immense change to the patients' lives, their families, and their freedom to speak.  

References

Mayoclinic (N.a). “Amyotrophic lateral sclerosis (ALS)”. Retrieved Aug 28, 2024, from https://www.mayoclinic.org/diseases-conditions/amyotrophic-lateral-sclerosis/symptoms-causes/syc-20354022 

Sciencedaily (Aug 14, 2024). “New brain-computer interface allows man with ALS to 'speak' again”. Retrieved Aug 28, 2024, from https://www.sciencedaily.com/releases/2024/08/240814170129.htm