O79 vibro-tactile evoked potentials (EPS) for assessment of consciousness and communication for people with disorders of consciousness. Issue 9 (September 2017)

• Record Type: Journal Article
• Authors: Ortner, Rupert; Fernandes, Francisco; Guger, Christoph; Heilinger, Alexander; Walchshofer, Martin; Gruenwald, Johannes
• Is Part Of: Clinical neurophysiology. Volume 128:Issue 9(2017:Sep.)
• Page Start: e204
• Publication Date: 2017-09
• Subjects: DOC -- EPs -- Evoked potentials -- Coma assessment -- Vibro-tactile -- EEG BCI -- P300; Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2017.07.090
• Languages: English
• ISSNs: 1388-2457

Abstract

Abstract : Objectives: The correct classification of patients in unresponsive wakefulness state (UWS) or minimally conscious state (MCS) is a challenge and misclassifications often occurre. In this publication we present a vibro-tactile EPs Brain-Computer Interface that serves for assessment of consciousness in and for communication. Methods: Patients are stimulated with two vibro-tactile tactors for consciousness assessment and three tactors for communication. The EEG is measured to calculate the evoked potentials as reactions to the stimuli. For assessment, the users had to follow predefined tasks, such as "count the stimuli you feel on your left hand". The BCI could then determine if the users were able to follow the task. In the communication runs the users were free to decide on which kind of stimuli they want to concentrate providing YES/NO answers. Three patients and three healthy controls are assessed. Results: All six participants were able to communicate in at least in one session. All EPs of the healthy subjects showed a P300 peak. Discussion: Visual inspection of the EPs shows that the P300 was generally not the main signal that differed between targets vs. nontargets. In most patient data, the normative P300 is not apparent, still the BCI was able to distinguish the EPs of single stimuli. Conclusions: We show which evoked potentials result in successful communication and provide online results of communication tests for all participants. Significance: Results further supports the nascent consensus that BCI technology could be helpful for assessment of awareness in these patients and for communication.