title: Conscious perception of brain states: mental strategies for brain-computer communication.
abstract: Direct brain-computer communication utilises self-regulation of brain potentials to select letters, words or symbols from a computer menu. In this study a completely paralysed (locked-in) patient learnt to produce slow cortical potential (SCP) shifts to operate a binary spelling device. After hundreds of training sessions he gave a detailed description of his mental strategies for self-regulation. His cognitive strategies matched with the electrocortical changes perfectly. Thus he produced a contingent negative variation (CNV) with images of preparation such as an arrow being drawn on a bow. To produce a positive potential shift he imagined the arrow shooting up from the bow. To suppress potential shifts he tried to stop thinking. The study demonstrates that patients become sensitive for their brain states with increasing self-regulation practice. The use of conscious cognitive strategies may, however, be incompatible with the complete automatization of the self-regulation skill.
authors.affiliation: Institute of Medical Psychology and Behavioral Neurobiology, University of Tuebingen, Gartenstrasse 29, D-72074 Tuebingen, Germany. nicola.neumann@uni-tuebingen.de
authors.forename: Nicola
authors.initials: N
authors.lastname: Neumann
authors.forename: Andrea
authors.initials: A
authors.lastname: Kübler
authors.forename: Jochen
authors.initials: J
authors.lastname: Kaiser
authors.forename: Thilo
authors.initials: T
authors.lastname: Hinterberger
authors.forename: Niels
authors.initials: N
authors.lastname: Birbaumer
mesh_terms: D000690:Amyotrophic Lateral Sclerosis / Q000503:physiopathology*; D001676:Biofeedback, Psychology; D001921:Brain; D003142:Communication; D003201:Computers; D003243:Consciousness; D003265:Contingent Negative Variation / Q000502:physiology; D004569:Electroencephalography / Q000379:methods; D005073:Evoked Potentials, Somatosensory; D006801:Humans; D007858:Learning; D008297:Male; D008606:Mental Processes; D008875:Middle Aged; D009483:Neuropsychological Tests; D010243:Paralysis / Q000503:physiopathology; D010465:Perception; D010775:Photic Stimulation; D011930:Reaction Time; D012927:Social Control, Informal / Q000379:methods; D014584:User-Computer Interface