Accuracy of a P300 speller for people with motor impairments

A Brain-Computer Interface (BCI) provides a completely new output pathway and so an additional possible way a person can express himself if he/she suffers disorders like amyotrophic lateral sclerosis (ALS), brainstem stroke, brain or spinal cord injury or other diseases which impair the function of the common output pathways which are responsible for the control of muscles or impair the muscles. Although most BCIs are thought to help people with disabilities, they are mainly tested on healthy, young subjects who may achieve better results than people with impairments. In this study we compare measurements, performed on 10 physically disabled people to the results of a previous study, taken of 100 healthy persons. We prove that, under certain constraints most patients are able to control a P300-based spelling device with almost the same accuracy than the healthy ones. Tuning parameters are discussed as well as criteria for people who are not able to use this device.