The P300 speller works by flashing a matrix, or random series of letters in front of a user
An Algoma University professor has made strides in developing technology that lets ALS patients compose emails without typing.
Computer science professor George Townsend has developed the P300 Speller, a device that measures and reacts to the brain’s “surprise element” to recognize of letters of the alphabet.
The interface consists of an EEG (electroencephalogram) amplifier, an electro-cap made of spandex, and small metal electrodes that are placed over the scalp.
When worn, the device measures minute electrical activity in the brain.
How it works
The speller works by flashing a matrix, or random series of letters in front of a user.
When the user sees, or recognizes, the letter they need to spell a word, the brain sends out a particular kind of brain activity — called the P300 response — and the attached computer responds by selecting the letter, then placing it into the word.
It’s a slow process, but for a patient that has lost other forms of communication, it could be essential.
Technology has been around for a few decades
Surprisingly, the technology isn’t new.
“This interface is thirty years old,” Townsend said, “but the evolution has been relatively slow over decades.”
His lab has managed to put that development into high gear, with Townsend claiming “vast improvements in the [interface’s] performance.”
So much improvement that his lab broke the world record for speed and accuracy for that type of interface.
Townsend’s lab shattered the record for speed and accuracy
Although the interface itself would be considered slow by computer users — the record holder spelled a 66-character sentence three times in a row, error free in as little as three minutes — Townsend hopes to make the device cost-effective enough to allow patients with ALS or Lou Gehrig’s disease to restore their ability to communicate..
“[ALS patients] cannot even have simple forms of communication, they can’t even breathe on their own,” Townsend said, “they lose all willful muscle control.”
“In that state, their brains are functioning completely normal. The can see and hear you, just can’t communicate. We call that the ‘locked-in syndrome.'”
For patients that have lost the ability to communicate, Townsend is pleased to refer to his device as “their last resort.”