A vibrotactile p300-based brain-computer interface for consciousness detection and communication.

[locked-in syndrome]

Brain -computer interface (BCI ) has been used for many years for communication in severely disabled patients . BCI based on electrophysiological signals has enabled communication , using auditory or visual stimuli to elicit event-related potentials (ERPs ). The aim of this study was to determine whether patients with locked-in syndrome (LIS ) could elicit a P 300 wave , using a vibrotactile oddball paradigm for establishing somatosensory BCI-based communication . Six chronic LIS patients performed 2 electroencephalography (EEG )-based vibrotactile P 300 oddball tasks . After a simple mental counting task of the target stimuli , participants were instructed to answer 5 questions by counting the vibration on either the right wrist for "yes " or the left wrist for "no ." All participants were able to elicit a P 300 wave using the vibrotactile oddball paradigm BCI task . In the counting task , 4 patients got accuracies of 100 % (average above chance ). In the communication task , one patient achieved 100 % accuracy (average above chance ). We have shown the feasibility of eliciting a P 300 response using vibrotactile stimulation in patients with LIS . The present study provides evidence that this approach can be used for EEG-based BCI communications in this patient group . This is the first study to prove the feasibility of a BCI based on somatosensory (vibratory ) stimulation in a group of brain -injured patients . Furthermore , this approach could be used for the detection of consciousness in non-communicating patients due to severe brain injuries .