A study at East Tennessee State University has shown that brain-computer interface (BCI) device can help patients with severe neuromuscular disease like brainstem stroke and are experiencing locked-in syndrome to communicate by enabling them to operate the device with their minds.
Earlier, brain-computer interface (BCI) devices have been proven effective in helping the patients with amyotrophic lateral sclerosis (ALS) – a degenerative nervous-system disorder that results in progressive muscle atrophy and paralysis – communicate during advanced stage of the disease.
According to Dr. Eric Sellers, who is the author of the study and an associate professor of Psychology in ETSU’s College of Arts and Sciences, the BCI device is submissive to a common brain response called the P300 – a positive spike in the brainwaves that lasts about 300 milliseconds, and can record brain activity using small sensors placed on the scalp.
The study used a P300-based event-related potential spelling system. For the patients, the P300 or the spike in brainwaves becomes a virtual finger which they will use to make a keystroke, using their thoughts of course.
During the test, the reseachers instruct the patients to pay attention to a specific “key” in a grid that represents a computer keyboard. The BCI arbitrarily flashes letters and numbers at a rapid rate, and the patient pays attention to the key they want to select. When that item flashes, the spike in brainwaves takes place and a computer screen displays the words and sentences the patients are trying to communicate. Thus, an individual locked-in owing to brainstem stroke was able to use a noninvasive BCI to communicate volitional messages.
“We have significant research showing that BCI is beneficial to ALS patients, but until now there were no studies that looked specifically at patients with a brainstem stroke to see if it worked for them as well,” Sellers said.
In the journal published in Science Translational Medicine, Dr. Eric Sellers claimed one of this patients with a brainstem stroke and a locked-in syndrome was able to successfully operate the BCI system during 40 of 62 sessions and could spell words accurately.
“Locked-in syndrome is associated with conditions other than ALS, and this study suggests that BCI may be useful regardless of the precipitating event that caused the condition,” Sellers said.
- Source: East Tennessee State University
- Reference: Non-invasive brain-computer interface enables communication after brainstem stroke [Science]
- Image: Dartmouth College