Another kind of 'BOLD Response': answering multiple-choice questions via online decoded single-trial brain signals
Graduate studies at Western
|Abstract||The term ‘locked-in’ syndrome (LIS) describes a medical condition in which persons concerned are severely paralyzed and at the same time fully conscious and awake. The resulting anarthria makes it impossible for these patients to naturally communicate, which results in diagnostic as well as serious practical and ethical problems. Therefore, developing alternative, muscle-independent communication means is of prime importance. Such communication means can be realized via brain–computer interfaces (BCIs) circumventing the muscular system by using brain signals associated with preserved cognitive, sensory, and emotional brain functions. Primarily, BCIs based on electrophysiological measures have been developed and applied with remarkable success. Recently, also blood ﬂow–based neuroimaging methods, such as functional magnetic resonance imaging (fMRI) and functional near-infrared spectroscopy (fNIRS), have been explored in this context. After reviewing recent literature on the development of especially hemodynamically based BCIs, we introduce a highly reliable and easy-to-apply communication procedure that enables untrained participants to motor-independently and relatively effortlessly answer multiple-choice questions based on intentionally generated single-trial fMRI signals that can be decoded online. Our technique takes advantage of the participants’ capability to voluntarily inﬂuence certain spatio-temporal aspects of the blood oxygenation level–dependent (BOLD) signal: source location (by using different mental tasks), signal onset and offset. We show that healthy participants are capable of hemodynamically encoding at least four distinct information units on a single-trial level without extensive pretraining and with little effort. Moreover, realtime data analysis based on simple multi-ﬁlter correlations allows for automated answer decoding with a high accuracy (94.9%) demonstrating the robustness of the presented method..|
|Keywords||No keywords specified (fix it)|
No categories specified
(categorize this paper)
|Through your library||Only published papers are available at libraries|
Similar books and articles
Andreas Bartels, fMRI and its Interpretations: An Illustration on Directional Selectivity in Area V5/MT.
Wolfgang Richter, Randy Summers, Seong-Gi Kim & Carola Tegeler, Motor Area Activity During Mental Rotation Studied by Time-Resolved Single-Trial fMRI.
Richard Heersmink (2011). Epistemological and Phenomenological Issues in the Use of Brain-Computer Interfaces. In C. Ess & R. Hagengruber (eds.), Proceedings of the International Association for Computing and Philosophy 2011 (pp. 98-102). MV-Wissenschaft.
Andrew Fenton & Sheri Alpert (2008). Extending Our View on Using BCIs for Locked-in Syndrome. Neuroethics 1 (2):119-132.
Agnès Aubert, Robert Costalat, Hugues Duffau & Habib Benali (2002). Modeling of Pathophysiological Coupling Between Brain Electrical Activation, Energy Metabolism and Hemodynamics: Insights for the Interpretation of Intracerebral Tumor Imaging. Acta Biotheoretica 50 (4).
Athena Demertzi & Mario Stanziano, Reaching Across the Abyss: Recent Advances in Functional Magnetic Resonance Imaging and Their Potential Relevance to Disorders of Consciousness.
Michel le Van Quyen & Antoine Lutz, Comparison of Hilbert Transform and Wavelet Methods for the Analysis of Neuronal Synchrony.
Jeremy Snyder (2010). Exploitations and Their Complications: The Necessity of Identifying the Multiple Forms of Exploitation in Pharmaceutical Trials. Bioethics 26 (5):251-258.
R. Allen Gardner (2007). A Brain for All Seasons. Behavioral and Brain Sciences 30 (1):93-94.
Sven Walter (2010). Locked-in Syndrome, Bci, and a Confusion About Embodied, Embedded, Extended, and Enacted Cognition. Neuroethics 3 (1):61-72.
Richard Heersmink (2011). Embodied Tools, Cognitive Tools and Brain-Computer Interfaces. Neuroethics. DOI 10.1007/S12152-011-9136-2 6 (1):207-219.
Added to index2010-12-22
Total downloads2 ( #247,687 of 751,836 )
Recent downloads (6 months)0
How can I increase my downloads?