https://medium.com/@Brainmab/hawkings-spelling-device-and-p300-3d7693e693d2

Stephen Hawking, one of the most revered scientists of our era, suffered from Amyotrophic Lateral Sclerosis (ALS). ALS is a neurodegenerative disease that mainly involves motor neurons responsible for voluntary muscle movement. The disease is progressive, meaning that it gets worse over time. There’s no cure for ALS, nor a method to halt, slow, or reverse the progression.

People suffering from ALS or similar debilitating conditions which disable the ability to “communicate”, need to use certain ‘helper’’ tools in order to be able communicate with the outside world. These devices usually gather some form of data from the user’s body, analyze it, and utilize the findings through a specific software in order to accomplish their task s — which are mostly generating sound or text. It is not an easy job to come up with a user-friendly device for people who have nearly zero voluntary control over their bodies, yet Hawking’s spelling device is a prime example and a great product in this category.