Analysis of sensorimotor rhythms for the implementation of a brain switch for healthy subjects

Abstract This paper presents an asynchronous brain switch using one Laplacian electroencephalographic (EEG) derivation. The brain switch is operated through foot motor imagery (MI) and is based on the classification of event-related desynchronization (ERD) during a motor task or event-related synchronization (ERS) after the termination of the task (also known as the beta rebound). The methods described in this work are suitable for operating a brain–computer interface (BCI) as an attractive control alternative for healthy users. A general description of ERD/ERS is obtained with several band power features and a rigid paradigm timing. Two support vector machines (SVMs) are trained in a novel fashion by using the patterns from motor execution (ME) and a priori information about the significance of ERD/ERS patterns. A maximum true positive rate (TPR) of 0.92 and a minimum of 0.43 was achieved (in 8 out of 9 subjects) during training of the classifiers; with a mean false positive rate (FPR) of 0.09 ± 0.05. A simulation of an asynchronous BCI using MI data and the classifiers trained with ME data achieved a maximum TPR of 0.88, a minimum of 0.50 (in 6 out of 9 subjects) and an average FPR of 0.09 ± 0.04. This work presents a step forward towards an easy-to-set-up and easy-to-use asynchronous BCI system for healthy users.

[1]  Chih-Jen Lin,et al.  Probability Estimates for Multi-class Classification by Pairwise Coupling , 2003, J. Mach. Learn. Res..

[2]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[3]  Gary E. Birch,et al.  A brain-controlled switch for asynchronous control applications , 2000, IEEE Trans. Biomed. Eng..

[4]  Karla Felix Navarro,et al.  A Comprehensive Survey of Brain Interface Technology Designs , 2007, Annals of Biomedical Engineering.

[5]  Gunnar Rätsch,et al.  An introduction to kernel-based learning algorithms , 2001, IEEE Trans. Neural Networks.

[6]  S. Makeig,et al.  Mining event-related brain dynamics , 2004, Trends in Cognitive Sciences.

[7]  Gert Pfurtscheller,et al.  Overt foot movement detection in one single Laplacian EEG derivation , 2008, Journal of Neuroscience Methods.

[8]  G. Pfurtscheller,et al.  Evidence for distinct beta resonance frequencies in human EEG related to specific sensorimotor cortical areas , 2001, Clinical Neurophysiology.

[9]  G. Pfurtscheller,et al.  Evaluation of event-related desynchronization (ERD) preceding and following voluntary self-paced movement. , 1979, Electroencephalography and clinical neurophysiology.

[10]  G. Pfurtscheller,et al.  Optimal spatial filtering of single trial EEG during imagined hand movement. , 2000, IEEE transactions on rehabilitation engineering : a publication of the IEEE Engineering in Medicine and Biology Society.

[11]  G. Pfurtscheller,et al.  Event-related beta EEG-changes during passive and attempted foot movements in paraplegic patients , 2007, Brain Research.

[12]  Desney S. Tan,et al.  Brain-Computer Interfacing for Intelligent Systems , 2008, IEEE Intelligent Systems.

[13]  F. L. D. Silva,et al.  Event-related EEG/MEG synchronization and desynchronization: basic principles , 1999, Clinical Neurophysiology.

[14]  M. Hallett,et al.  Classifying EEG signals preceding right hand, left hand, tongue, and right foot movements and motor imageries , 2008, Clinical Neurophysiology.

[15]  G. Birch,et al.  Initial on-line evaluations of the LF-ASD brain-computer interface with able-bodied and spinal-cord subjects using imagined voluntary motor potentials , 2002, IEEE Transactions on Neural Systems and Rehabilitation Engineering.

[16]  G. Pfurtscheller,et al.  Brain-Computer Interfaces for Communication and Control. , 2011, Communications of the ACM.

[17]  G. Pfurtscheller,et al.  Could the beta rebound in the EEG be suitable to realize a “brain switch”? , 2009, Clinical Neurophysiology.

[18]  Gernot R. Müller-Putz,et al.  Game-like Training to Learn Single Switch Operated Neuroprosthetic Control , 2007 .

[19]  G. Pfurtscheller,et al.  Brain–Computer Communication: Motivation, Aim, and Impact of Exploring a Virtual Apartment , 2007, IEEE Transactions on Neural Systems and Rehabilitation Engineering.

[20]  Horst Bischof,et al.  Toward Self-Paced Brain–Computer Communication: Navigation Through Virtual Worlds , 2008, IEEE Transactions on Biomedical Engineering.

[21]  R. Hari,et al.  Functional Segregation of Movement-Related Rhythmic Activity in the Human Brain , 1995, NeuroImage.

[22]  Klaus-Robert Müller,et al.  The non-invasive Berlin Brain–Computer Interface: Fast acquisition of effective performance in untrained subjects , 2007, NeuroImage.

[23]  M. Hallett,et al.  A high performance sensorimotor beta rhythm-based brain–computer interface associated with human natural motor behavior , 2008, Journal of neural engineering.

[24]  J B Poline,et al.  Partially overlapping neural networks for real and imagined hand movements. , 2000, Cerebral cortex.

[25]  B. Hjorth.  An on-line transformation of EEG scalp potentials into orthogonal source derivations. , 1975, Electroencephalography and clinical neurophysiology.

[26]  Vilayanur S. Ramachandran,et al.  EEG evidence for mirror neuron activity during the observation of human and robot actions: Toward an analysis of the human qualities of interactive robots , 2007, Neurocomputing.

[27]  Anthony C. Davison,et al.  Bootstrap Methods and Their Application , 1998 .

[28]  G Pfurtscheller,et al.  Toward a hybrid brain–computer interface based on imagined movement and visual attention , 2010, Journal of neural engineering.

[29]  M Fatourechi,et al.  A self-paced brain–computer interface system with a low false positive rate , 2008, Journal of neural engineering.

[30]  G. Pfurtscheller,et al.  Continuous EEG classification during motor imagery-simulation of an asynchronous BCI , 2004, IEEE Transactions on Neural Systems and Rehabilitation Engineering.

[31]  G. Pfurtscheller,et al.  Motor imagery activates primary sensorimotor area in humans , 1997, Neuroscience Letters.

[32]  G. R. Muller,et al.  Event-related beta EEG changes during wrist movements induced by functional electrical stimulation of forearm muscles in man , 2003, Neuroscience Letters.