Article

Amyotrophic lateral sclerosis (ALS), a progressive neurodegenerative
disease, restricts patients' communication capacity a few years after onset. A
proof-of-concept of brain-computer interface (BCI) has shown promise in ALS and
"locked-in" patients, mostly in pre-clinical studies or with only a few patients,
but performance was estimated not high enough to support adoption by people with
physical limitation of speech. Here, we evaluated a visual BCI device in a
clinical study to determine whether disabled people with multiple deficiencies
related to ALS would be able to use BCI to communicate in a daily environment.
METHODS: After clinical evaluation of physical, cognitive and language
capacities, 20 patients with ALS were included. The P300 speller BCI system
consisted of electroencephalography acquisition connected to real-time processing
software and separate keyboard-display control software. It was equipped with
original features such as optimal stopping of flashes and word prediction. The
study consisted of two 3-block sessions (copy spelling, free spelling and free
use) with the system in several modes of operation to evaluate its usability in
terms of effectiveness, efficiency and satisfaction. RESULTS: The system was
effective in that all participants successfully achieved all spelling tasks and
was efficient in that 65% of participants selected more than 95% of the correct
symbols. The mean number of correct symbols selected per minute ranged from 3.6
(without word prediction) to 5.04 (with word prediction). Participants expressed
satisfaction: the mean score was 8.7 on a 10-point visual analog scale assessing
comfort, ease of use and utility. Patients quickly learned how to operate the
system, which did not require much learning effort. CONCLUSION: With its word
prediction and optimal stopping of flashes, which improves information transfer
rate, the BCI system may be competitive with alternative communication systems
such as eye-trackers. Remaining requirements to improve the device for suitable
ergonomic use are in progress.
CI - Copyright (c) 2017. Published by Elsevier Masson SAS.

Langue : ANGLAIS