title: A device for the detection of cognitive brain functions in completely paralyzed or unresponsive patients.
abstract: Unresponsive patients with remaining cognitive abilities may be able to communicate with a brain-computer interface (BCI) such as the Thought Translation Device (TTD). Before initiating TTD learning, which may imply considerable effort, it is important to classify the patients' state of awareness and their remaining cognitive abilities. A tool for detection of cognitive activity (DCA) in the completely paralyzed was developed and integrated into the TTD which is a psychophysiological system for direct brain communication. In the present version, DCA entails five event-related brain-potential (ERP) experiments and investigates the capability of a patient to discriminate, e.g., between semantically related and unrelated concepts and categories. ERPs serve as an indicator of the patients' cortical information processing. Data from five severely brain-injured patients in persistent vegetative state diagnosed as unresponsive and five healthy controls are presented to illustrate the methodology. Two patients showing the highest responsiveness were selected for TTD training. The DCA integrated in the TTD allows screening of cognitive abilities and direct brain communication in the patients' home.
authors.affiliation: Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen 72074, Germany. thilo.hinterberger@uni-tuebingen.de
authors.forename: Thilo
authors.initials: T
authors.lastname: Hinterberger
authors.forename: Barbara
authors.initials: B
authors.lastname: Wilhelm
authors.forename: Jürgen
authors.initials: J
authors.lastname: Mellinger
authors.forename: Boris
authors.initials: B
authors.lastname: Kotchoubey
authors.forename: Niels
authors.initials: N
authors.lastname: Birbaumer
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D001921:Brain / Q000503:physiopathology*; D003071:Cognition; D003143:Communication Devices for People with Disabilities; D003936:Diagnosis, Computer-Assisted / Q000379:methods; D004569:Electroencephalography / Q000379:methods*; D005071:Evoked Potentials; D006801:Humans; D008875:Middle Aged; D018458:Persistent Vegetative State / Q000503:physiopathology* / Q000534:rehabilitation*; D014584:User-Computer Interface