ScienceDirect - Journal of Physiology-Paris : A review on directional information in neural signals for brain-machine interfaces

Journal of Physiology-Paris
Volume 103, Issues 3-5, September 2009, Pages 244-254
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doi:10.1016/j.jphysparis.2009.08.007

A review on directional information in neural signals for brain-machine interfaces

Stephan Waldert^a^,^b^,^,¹^,, Tobias Pistohl^a^,^b^,¹^,, Christoph Braun^c^,^d^,, Tonio Ball^a^,^b^,^e^,, Ad Aertsen^a^,^b^, and Carsten Mehring^a^,^b^,^,

^aFaculty of Biology, Albert-Ludwigs-University, Hauptstr. 1, 79104 Freiburg, Germany

^bBernstein Center for Computational Neuroscience, Hansastr. 9a, 79104 Freiburg, Germany

^cMEG-Center, University of Tübingen, Tübingen, Germany

^dCIMeC, Center of Mind/Brain Sciences, University of Trento, Trento, Italy

^eEpilepsy Center, University Clinics, Albert-Ludwigs University, Freiburg, Germany

Available online 7 August 2009.

Abstract

Brain-machine interfaces (BMIs) can be characterized by the technique used to measure brain activity and by the way different brain signals are translated into commands that control an effector. We give an overview of different approaches and focus on a particular BMI approach: the movement of an artificial effector (e.g. arm prosthesis to the right) by those motor cortical signals that control the equivalent movement of a corresponding body part (e.g. arm movement to the right). This approach has been successfully applied in monkeys and humans by accurately extracting parameters of movements from the spiking activity of multiple single-units. Here, we review recent findings showing that analog neuronal population signals, ranging from intracortical local field potentials over epicortical ECoG to non-invasive EEG and MEG, can also be used to decode movement direction and continuous movement trajectories. Therefore, these signals might provide additional or alternative control for this BMI approach, with possible advantages due to reduced invasiveness.

Keywords: Directional tuning; Decoding; SUA; MUA; LFP; ECoG; EEG; MEG; BMI; BCI

Article Outline

1. Introduction
2. Directional tuning
3. Movement decoding
4. Discussion
Acknowledgements
Appendix A
References

Corresponding authors. Address: Faculty of Biology, Hauptstr. 1, 79104 Freiburg, Germany. Tel.: +49 761 203 2542; fax: +49 761 203 2921 (S. Walbert), tel.: +49 761 203 2543; fax: +49 761 203 2921 (C. Mehring).
¹ These authors contributed equally to the manuscript.