An auditory oddball brain–computer interface for binary choices

Halder, S.; Rea, M.; Andreoni, R.; Nijboer, F.; Hammer, E.M.; Kleih, S.C.; Birbaumer, N.; Kübler, A.

doi:10.1016/j.clinph.2009.11.087

« Previous Next »Clinical Neurophysiology
Volume 121, Issue 4 , Pages 516-523, April 2010

An auditory oddball brain–computer interface for binary choices

S. Halder
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Gartenstr. 29, 72074 Tübingen, Germany
- Wilhelm-Schickard Institute for Computer Engineering, University of Tübingen, Sand 13, 72076 Tübingen, Germany
- Corresponding author. Address: Institute of Medical Psychology and Behavioral Neurobiology Gartenstr. 29, 72074 Tübingen, Germany. Tel.: +49 (0)7071 2978358; fax: +49 (0)7071 295956.
- These authors contributed equally to the paper.
M. Rea
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Gartenstr. 29, 72074 Tübingen, Germany
- These authors contributed equally to the paper.
R. Andreoni
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Gartenstr. 29, 72074 Tübingen, Germany
- These authors contributed equally to the paper.
F. Nijboer
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Gartenstr. 29, 72074 Tübingen, Germany
E.M. Hammer
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Gartenstr. 29, 72074 Tübingen, Germany
S.C. Kleih
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Gartenstr. 29, 72074 Tübingen, Germany
N. Birbaumer
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Gartenstr. 29, 72074 Tübingen, Germany
- Ospedale San Camillo, Istituto di Ricovero e Cura a Carattere Scientifico, Via Alberoni 70, 30126 Venezia, Italy
A. Kübler
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Gartenstr. 29, 72074 Tübingen, Germany
- Department of Psychology I, University of Würzburg, Marcusstr. 9-11, 97070 Würzburg, Germany

Accepted 27 November 2009.

Abstract

Objective

Brain–computer interfaces (BCIs) provide non-muscular communication for individuals diagnosed with late-stage motoneuron disease (e.g., amyotrophic lateral sclerosis (ALS)). In the final stages of the disease, a BCI cannot rely on the visual modality. This study examined a method to achieve high accuracies using auditory stimuli only.

Methods

We propose an auditory BCI based on a three-stimulus paradigm. This paradigm is similar to the standard oddball but includes an additional target (i.e. two target stimuli, one frequent stimulus). Three versions of the task were evaluated in which the target stimuli differed in loudness, pitch or direction.

Results

Twenty healthy participants achieved an average information transfer rate (ITR) of up to 2.46bits/min and accuracies of 78.5%. Most subjects (14 of 20) achieved their best performance with targets differing in pitch.

Conclusions

With this study, the viability of the paradigm was shown for healthy participants and will next be evaluated with individuals diagnosed with ALS or locked-in syndrome (LIS) after stroke.

Significance

The here presented BCI offers communication with binary choices (yes/no) independent of vision. As it requires only little time per selection, it may constitute a reliable means of communication for patients who lost all motor function and have a short attention span.

Keywords: EEG, BCI, ERP, P300, Oddball, Auditory