A Brain–Computer Interface Speller with a Reduced Matrix: A Case Study in a Patient with Amyotrophic Lateral Sclerosis

Visual P300-based Brain–Computer Interface (BCI) paradigms for spelling are aimed at offering a non-muscular communication channel for those people with severe motor impairment, such as locked-in patients. To be as effective as other assistive technologies, these systems have to achieve a greater communication rate. One way to do so is to develop better interfaces. In this regard, we thought of using a 4 x 3 symbol matrix based on the T9 interface developed for mobile phones. Due to presenting a reduced matrix and relying on an adaptation of the T9 predictive text system, we expected that this speller would provide a higher communication rate than usual 6 x 6 matrix spellers that are based on Farwell and Donchin’s classic proposal. As a proof of concept, a locked-in patient with amyotrophic lateral sclerosis tested our T9-like visual BCI speller along with two different 7 x 6 conventional matrix spellers. The comparison of her performance results with those of a sample of three healthy participants suggested that it was possible for this locked-in patient to control the T9-like speller as well as they did, and thus, write a target sentence considerably faster than when she used the alternative spellersUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

BCI-Controlled Wheelchair; Audio-Cue Motor Imagery-Based Paradigm

In this study we present a control paradigm that enables subjects to drive a real wheelchair using four navigation commands. The control is achieved through the discrimination of two mental tasks (relaxed state versus one active Motor imaagery task), in order to reduce the risk of misclassification. After a short training, the paradigm becomes only audio-cued, thus avoiding the need of a graphical interface that could distract subjects’ attention.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Control de una silla de ruedas a través de un sistema BCI basado en la discriminación de dos tareas mentales

Dicho trabajo ha sido publicado en la revista Cognitive Area Networks, vol. 1, nº1, junio 2014, pp. 43-48.En este trabajo se presenta una propuesta de control de una silla de ruedas a través de una interfaz cerebro computadora mediante la discriminación de sólo dos tareas mentales. Con el paradigma de control propuesto se pretende minimizar los porcentajes de error en la clasificación de estados mentales, proporcionando a su vez un conjunto suficiente de comandos que permita dirigir la silla de ruedas en todas direcciones (avanzar, retroceder, girar a la derecha, girar a la izquierda y parar).Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech