Brain–computer interface using a simplified functional near-infrared spectroscopy system

A brain-computer interface (BCI) is a device that allows a user to communicate with external devices through thought processes alone. A novel signal acquisition tool for BCIs is near-infrared spectroscopy (NIRS), an optical technique to measure localized cortical brain activity. The benefits of using this non-invasive modality are safety, portability and accessibility. A number of commercial multi-channel NIRS system are available; however we have developed a straightforward custom-built system to investigate the functionality of a fNIRS-BCI system. This work describes the construction of the device, the principles of operation and the implementation of a fNIRS-BCI application, 'Mindswitch' that harnesses motor imagery for control. Analysis is performed online and feedback of performance is presented to the user. Mindswitch presents a basic 'on/off' switching option to the user, where selection of either state takes 1 min. Initial results show that fNIRS can support simple BCI functionality and shows much potential. Although performance may be currently inferior to many EEG systems, there is much scope for development particularly with more sophisticated signal processing and classification techniques. We hope that by presenting fNIRS as an accessible and affordable option, a new avenue of exploration will open within the BCI research community and stimulate further research in fNIRS-BCIs.

[1]  N. Chater,et al.  Shedding light on brain function : the event-related optical signal , 2001 .

[2]  Cuntai Guan,et al.  Temporal classification of multichannel near-infrared spectroscopy signals of motor imagery for developing a brain–computer interface , 2007, NeuroImage.

[3]  Shirley Coyle,et al.  On the suitability of near-infrared (NIR) systems for next-generation brain-computer interfaces. , 2004, Physiological measurement.

[4]  M. Herrmann,et al.  Frontal activation during a verbal-fluency task as measured by near-infrared spectroscopy , 2003, Brain Research Bulletin.

[5]  Christa Neuper,et al.  Walking by Thinking: The Brainwaves Are Crucial, Not the Muscles! , 2006, PRESENCE: Teleoperators and Virtual Environments.

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

[7]  William Z Rymer,et al.  Guest Editorial Brain–Computer Interface Technology: A Review of the Second International Meeting , 2001 .

[8]  S. Coyle,et al.  An optical brain computer interface , 2004 .

[9]  Martin Wolf,et al.  Functional Frequency-Domain Near-Infrared Spectroscopy Detects Fast Neuronal Signal in the Motor Cortex , 2002, NeuroImage.

[10]  A. Villringer,et al.  Noninvasive monitoring of cerebral blood flow by a dye bolus method: separation of brain from skin and skull signals. , 2002, Journal of biomedical optics.

[11]  S. Coyle,et al.  Cerebral Blood Flow Changes related to Motor Imagery, using Near-infrared Spectroscopy (NIRS) , 2003 .

[12]  J. Wolpaw,et al.  Brain-computer communication: unlocking the locked in. , 2001, Psychological bulletin.

[13]  Soo-Young Lee,et al.  Brain–computer interface using fMRI: spatial navigation by thoughts , 2004, Neuroreport.

[14]  E Donchin,et al.  Brain-computer interface technology: a review of the first international meeting. , 2000, IEEE transactions on rehabilitation engineering : a publication of the IEEE Engineering in Medicine and Biology Society.

[15]  Ranulfo Romo,et al.  Language Abilities of Motor Cortex , 2004, Neuron.

[16]  D. Delpy,et al.  System for long-term measurement of cerebral blood and tissue oxygenation on newborn infants by near infra-red transillumination , 1988, Medical and Biological Engineering and Computing.

[17]  A. Villringer,et al.  Near infrared spectroscopy (NIRS): A new tool to study hemodynamic changes during activation of brain function in human adults , 1993, Neuroscience Letters.

[18]  A. Villringer,et al.  Non-invasive optical spectroscopy and imaging of human brain function , 1997, Trends in Neurosciences.

[19]  D. Delpy,et al.  Investigation of Cerebral Haemodynamics by Near-infrared Spectroscopy in Young Healthy Volunteers Reveals Posture-dependent Spontaneous Oscillations , 2004 .

[20]  S. Coyle,et al.  Physiological noise in near-infrared spectroscopy: implications for optical brain computer interfacing , 2004, The 26th Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[21]  G. Pfurtscheller,et al.  Imagery of motor actions: differential effects of kinesthetic and visual-motor mode of imagery in single-trial EEG. , 2005, Brain research. Cognitive brain research.

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

[23]  G Pfurtscheller,et al.  Current trends in Graz Brain-Computer Interface (BCI) research. , 2000, IEEE transactions on rehabilitation engineering : a publication of the IEEE Engineering in Medicine and Biology Society.

[24]  M. Tamura,et al.  Detection of dynamic changes in cerebral oxygenation coupled to neuronal function during mental work in man , 1993, Neuroscience Letters.

[25]  D. Boas,et al.  Non-invasive neuroimaging using near-infrared light , 2002, Biological Psychiatry.

[26]  David A. Boas,et al.  Factors affecting the accuracy of near-infrared spectroscopy concentration calculations for focal changes in oxygenation parameters , 2003, NeuroImage.

[27]  Thomas Elbert,et al.  Seeing right through you: applications of optical imaging to the study of the human brain. , 2003, Psychophysiology.

[28]  Michael Erb,et al.  Physiological self-regulation of regional brain activity using real-time functional magnetic resonance imaging (fMRI): methodology and exemplary data , 2003, NeuroImage.

[29]  P. Rolfe,et al.  In vivo near-infrared spectroscopy. , 2000, Annual review of biomedical engineering.