Brain-computer communication: self-regulation of slow cortical potentials for verbal communication.
OBJECTIVE
To test a training procedure designed to enable severely paralyzed patients to communicate by means of self-regulation of slow cortical potentials.


METHODS
Application of the Thought Translation Device to evaluate the procedure in patients with late-stage amyotrophic lateral sclerosis (ALS).


METHODS
Training sessions in the patients' homes.


METHODS
Two male patients with late-stage ALS.


METHODS
Patients learned voluntary control of their slow cortical potentials by means of an interface between the brain and a computer. Training was based on visual feedback of slow cortical potentials shifts and operant learning principles. The learning process was divided into small steps of increasing difficulty.


METHODS
Accuracy of self-control of slow cortical potentials (percentage of correct responses). Learning progress calculated as a function of training session.


RESULTS
Within 3 to 8 weeks, both patients learned to self-regulate their slow cortical potentials and to use this skill to select letters or words in the Language Support Program.


CONCLUSIONS
This training schedule is the first to enable severely paralyzed patients to communicate without any voluntary muscle control by using self-regulation of an electroencephalogram potential only. The protocol could be a model for training patients in other brain-computer interface techniques.
Kübler
A
A
Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany. andrea.kuebler@uni-tuebingen.de
Neumann
N
N
Kaiser
J
J
Kotchoubey
B
B
Hinterberger
T
T
Birbaumer
N P
NP
D000328:Adult; D000690:Amyotrophic Lateral Sclerosis / Q000503:physiopathology*; D001676:Biofeedback, Psychology; D001921:Brain / Q000503:physiopathology*; D003143:Communication Devices for People with Disabilities; D003216:Conditioning, Operant; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010243:Paralysis / Q000503:physiopathology*; D018709:Statistics, Nonparametric; D014584:User-Computer Interface