Brain-computer interfaces in medicine

Mayo Clinic Proceedings

Volumn 87, Issue 3, 2012, Pages 268-279

  Shih, Jerry J ^a   Krusienski, Dean J ^b   Wolpaw, Jonathan R ^c  

^a MAYO CLINIC   (United States)

^b Old Dominion University   (United States)

^c STATE UNIVERSITY OF NEW YORK   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ALGORITHM; BRAIN COMPUTER INTERFACE; BRAIN CORTEX; BRAIN DEPTH RECORDING; BRAIN REGION; DATA EXTRACTION; ELECTROENCEPHALOGRAM; ELECTROENCEPHALOGRAPHY; HUMAN; INFORMATION DISSEMINATION; LATENT PERIOD; MEDICAL TECHNOLOGY; NEUROMODULATION; NONHUMAN; PHYSIOLOGICAL PROCESS; RELIABILITY; REVIEW; ROBOTICS; SCALP; SENSORY FEEDBACK; SIGNAL PROCESSING; SYNAPTIC TRANSMISSION; TRANSLATIONAL RESEARCH; VALIDATION PROCESS;

EID: 84857993132     PISSN: 00256196     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.mayocp.2011.12.008     Document Type: Review

References (126)

1. Wolpaw JR, Wolpaw EW, eds. Brain-Computer Interfaces: Principles and Practice. New York, NY: Oxford University Press; 2012.
2. Vidal JJ. Toward direct brain-computer communication. Annu Rev Biophys Bioeng. 1973;2:157-180.
3. Fetz EE. Operant conditioning of cortical unit activity. Science. 1969;163(3870):955-958.
4. Elbert T, Rockstroh B, Lutzenberger W, Birbaumer N. Biofeedback of slow cortical potentials. I. Electroencephalogr Clin Neurophysiol. 1980;48(3):293-301. (Pubitemid 10144863)
5. Farwell LA, Donchin E. Talking off the top of your head: toward a mental prosthesis utilizing event-related brain potentials. Electroencephalogr Clin Neurophysiol. 1988;70(6):510-523.
6. Gastaut H. Electrocorticographic study of the reactivity of rolandic rhythm. Rev Neurol (Paris). 1952;87:176-182.
7. Kuhlman WN. EEG feedback training: enhancement of somatosensory cortical activity. Electroencephalogr Clin Neurophysiol. 1978;45(2):290-294. (Pubitemid 8392403)
8. Wolpaw JR, McFarland DJ. Multichannel EEG-based braincomputer communication. Electroencephalogr Clin Neurophysiol. 1994;90(6):444-449.
9. Wolpaw JR, McFarland DJ, Neat GW, Forneris CA. An EEG-based brain-computer interface for cursor control. Electroencephalogr Clin Neurophysiol. 1991;78(3):252-259.
10. Wolpaw JR, McFarland DJ. Control of a two-dimensional movement signal by a noninvasive brain-computer interface in humans. Proc Natl Acad Sci U S A. 2004;101(51):17849-17854. (Pubitemid 40051975)
11. Hochberg LR, Serruya MD, Friehs GM, et al. Neuronal ensemble control of prosthetic devices by a human with tetraplegia. Nature. 2006;442(7099):164-171. (Pubitemid 44086558)
12. Krusienski DJ, Shih JJ. Control of a visual keyboard using an electrocorticographic brain-computer interface. Neurorehabil Neural Repair. 2011;25(4):323-331.
13. Vaughan TM, Wolpaw JR. The Third International Meeting on Brain-Computer Interface Technology: making a difference. IEEE Trans Neural Syst Rehabil Eng. 2006;14(2):126-127. (Pubitemid 44150223)
14. Berger H. Uber das electrenkephalogramm des menchen. Arch Psychiatr Nervenkr. 1929;87:527-570.
15. Akhtari M, Bryant HC, Mamelak AN, et al. Conductivities of three-layer human skull. Brain Topogr. 2000;13(1):29-42.
16. Krusienski DJ, Shih JJ. Control of a brain-computer interface using stereotactic depth electrodes in and adjacent to the hippocampus. J Neural Eng. 2011;8(2):025006.
17. Shih JJ, Krusienski DJ. Signals from intraventricular depth electrodes can control a brain-computer interface. J Neurosci Methods. 2012;203(2):311-314.
18. Mellinger J, Schalk G, Braun C, et al. An MEG-based brain-computer interface (BCI). Neuroimage. 2007;36(3):581-593. (Pubitemid 46915502)
19. van Gerven M, Jensen O. Attention modulations of posterior alpha as a control signal for two-dimensional brain-computer interfaces. J Neurosci Methods. 2009;179(1):78-84.
20. Lee JH, Ryu J, Jolesz FA, Cho ZH, Yoo SS. Brain-machine interface via real-time fMRI: preliminary study on thought-controlled robotic arm. Neurosci Lett. 2009;450(1):1-6.
21. Mak JN, Wolpaw JR. Clinical applications of brain-computer interfaces: current state and future prospects. IEEE Rev Biomed Eng. 2009;2:187-199.
22. Wolpaw JR, Birbaumer N, McFarland DJ, Pfurtscheller G, Vaughan TM. Brain-computer interfaces for communication and control. Clin Neurophysiol. 2002;113(6):767-791. (Pubitemid 34621187)
23. McFarland DJ, Krusienski DJ, Sarnacki WA, Wolpaw JR. Emulation of computer mouse control with a noninvasive brain-computer interface. J Neural Eng. 2008;5(2):101-110. (Pubitemid 351999178)
24. Kayagil TA, Bai O, Henriquez CS, et al. A binary method for simple and accurate two-dimensional cursor control from EEG with minimal subject training. J Neuroeng Rehabil. 2009;6(May 6):14.
25. McFarland DJ, Sarnacki WA, Wolpaw JR. Electroencephalographic (EEG) control of three-dimensional movement. J Neural Eng. 2010;7(3):036007.
26. Doud AJ, Lucas JP, Pisansky MT, He B. Continuous three-dimensional control of a virtual helicopter using a motor imagery based brain-computer interface. PLoS One. 2011;6(10):e26322.
27. Neuper C, Muller-Putz GR, Scherer R, Pfurtscheller G. Motor imagery and EEG-based control of spelling devices and neuroprostheses. Prog Brain Res. 2006;159:393-409. (Pubitemid 44634656)
28. Cincotti F, Mattia D, Aloise F, et al. Non-invasive brain-computer interface system: towards its application as assistive technology. Brain Res Bull. 2008;75(6):796-803.
29. Pfurtscheller G, Guger C, Muller G, Krausz G, Neuper C. Brain oscillations control hand orthosis in a tetraplegic. Neurosci Lett. 2000;292(3):211-214.
30. Pfurtscheller G, Muller GR, Pfurtscheller J, Gerner HJ, Rupp R. 'Thought'-control of functional electrical stimulation to restore hand grasp in a patient with tetraplegia. Neurosci Lett. 2003;351(1):33-36. (Pubitemid 37205178)
31. McFarland DJ, Wolpaw JR. Brain-computer interface operation of robotic and prosthetic devices. Computer. 2010;41:52-56.
32. Muller-Putz GR, Scherer R, Pfurtscheller G, Rupp R. EEG-based neuroprosthesis control: a step towards clinical practice. Neurosci Lett. 2005(1-2);382:169-174. (Pubitemid 40725887)
33. Galan F, Nuttin M, Lew E, et al. A brain-actuated wheelchair: asynchronous and non-invasive Brain-computer interfaces for continuous control of robots. Clin Neurophysiol. 2008(9);119:2159-2169.
34. Tanaka K, Matsunaga K, Wang HO. Electroencephalogram-based control of an electric wheelchair. IEEE Trans Robotics. 2005;21:762-766. (Pubitemid 41226906)
35. Hoffmann U, Vesin JM, Ebrahimi T, Diserens K. An efficient P300-based brain-computer interface for disabled subjects. J Neurosci Methods. 2008;167(1):115-125. (Pubitemid 350180084)
36. Krusienski DJ, Sellers EW, McFarland DJ, Vaughan TM, Wolpaw JR. Toward enhanced P300 speller performance. J Neurosci Methods. 2008;167(1):15-21. (Pubitemid 350180088)
37. Nijboer F, Sellers EW, Mellinger J, et al. A P300-based brain-computer interface for people with amyotrophic lateral sclerosis. Clin Neurophysiol. 2008;119(8):1909-1916.
38. Piccione F, Giorgi F, Tonin P, et al. P300-based brain computer interface: reliability and performance in healthy and paralysed participants. Clin Neurophysiol. 2006;117(3):531-537. (Pubitemid 43343985)
39. Sellers EW, Donchin E. A P300-based brain-computer interface: initial tests by ALS patients. Clin Neurophysiol. 2006;117(3):538-548. (Pubitemid 43343986)
40. Sellers EW, Kubler A, Donchin E. Brain-computer interface research at the University of South Florida Cognitive Psychophysiology Laboratory: the P300 Speller. IEEE Trans Neural Syst Rehabil Eng. 2006;14(2):221-224. (Pubitemid 44150247)
41. Sellers E W, Vaughan T M, Wolpaw J R. A brain-computer interface for long-term independent home use. Amyotroph Lateral Scler. 2010;11(5):449-455.
42. Vaughan TM, McFarland DJ, Schalk G, et al. The Wadsworth BCI Research and Development Program: at home with BCI. IEEE Trans Neural Syst Rehabil Eng. 2006;14(2):229-233. (Pubitemid 44150249)
43. Mugler EM, Ruf CA, Halder S, Bensch M, Kubler A. Design and implementation of a P300-based brain-computer interface for controlling an internet browser. IEEE Trans Neural Syst Rehabil Eng. 2010;18(6):599-609.
44. Pires G, Castelo-Branco M, Nunes U. Visual P300-based BCI to steer a wheelchair: a Bayesian approach. Conf Proc IEEE Eng Med Biol Soc. 2008;2008:658-661.
45. Rebsamen B, Burdet E, Guan C, et al. Controlling a wheelchair indoors using thought. IEEE Intelligent Systems. 2007;22:18-24. (Pubitemid 46495741)
46. Rebsamen B, Guan C, Zhang H, et al. A brain controlled wheelchair to navigate in familiar environments. IEEE Trans Neural Syst Rehabil Eng. 2010;18(6):590-598.
47. Vanacker G, del R Millan J, Lew E, et al. Context-based filtering for assisted brain-actuated wheelchair driving. Comput Intell Neurosci. 2007:25130.
48. Allison BZ, McFarland DJ, Schalk G, Zheng SD, Jackson MM, Wolpaw JR. Towards an independent brain-computer interface using steady state visual evoked potentials. Clin Neurophysiol. 2008;119(2):399-408. (Pubitemid 50013927)
49. Kelly SP, Lalor EC, Finucane C, McDarby G, Reilly RB. Visual spatial attention control in an independent brain-computer interface. IEEE Trans Biomed Eng. 2005;52(9):1588-1596. (Pubitemid 41462189)
50. Kelly SP, Lalor EC, Reilly RB, Foxe JJ. Visual spatial attention tracking using high-density SSVEP data for independent brain-computer communication. IEEE Trans Neural Syst Rehabil Eng. 2005;13(2):172-178. (Pubitemid 41017704)
51. Sutter EE. The brain response interface: communication through visually-induced electrical brain responses. J Microcomputer Applications. 1992;15:31-45.
52. Trejo LJ, Rosipal R, Matthews B. Brain-computer interfaces for 1-D and 2-D cursor control: designs using volitional control of the EEG spectrum or steady-state visual evoked potentials. IEEE Trans Neural Syst Rehabil Eng. 2006;14(2):225-229. (Pubitemid 44150248)
53. Muller-Putz GR, Pfurtscheller G. Control of an electrical prosthesis with an SSVEP-based BCI. IEEE Trans Biomed Eng. 2008;55(1):361-364. (Pubitemid 350308399)
54. Gollee H, Volosyak I, McLachlan AJ, Hunt KJ, Graser A. An SSVEP-based brain-computer interface for the control of functional electrical stimulation. IEEE Trans Biomed Eng. 2010;57(8):1847-1855.
55. Middendorf M, McMillan G, Calhoun G, Jones KS. Brain-computer interfaces based on the steady-state visual-evoked response. IEEE Trans Rehabil Eng. 2000;8(2):211-214. (Pubitemid 30437017)
56. Cecotti H. A self-paced and calibration-less SSVEP-based brain-computer interface speller. IEEE Trans Neural Syst Rehabil Eng. 2010;18(2):127-133.
57. Gao X, Xu D, Cheng M, Gao S. A BCI-based environmental controller for the motion-disabled. IEEE Trans Neural Syst Rehabil Eng. 2003;11(2):137-140. (Pubitemid 36935041)
58. Furdea A, Halder S, Krusienski D J, et al. An auditory oddball (P300) spelling system for brain-computer interfaces. Psychophysiology. 2009;46(3):617-625.
59. Hinterberger T, Neumann N, Pham M, et al. A multimodal brain-based feedback and communication system. Exp Brain Res. 2004;154(4):521-526. (Pubitemid 38293743)
60. Kubler A, Furdea A, Halder S, Hammer EM, Nijboer F, Kotchoubey B. A brain-computer interface controlled auditory event-related potential (p300) spelling system for locked-in patients. Ann N Y Acad Sci. 2009;1157:90-100.
61. Schreuder M, Blankertz B, Tangermann M. A new auditory multi-class brain-computer interface paradigm: spatial hearing as an informative cue. PLoS One. 2010;5(4):e9813.
62. Brouwer AM, Erp JB. A tactile P300 brain-computer interface. Front Neurosci. 2010;4:19.
63. Chatterjee A, Aggarwal V, Ramos A, Acharya S, Thakor NV. A brain-computer interface with vibrotactile biofeedback for haptic information. J Neuroeng Rehabil. 2007;4:40.
64. Cincotti F, Kauhanen L, Aloise F, et al. Vibrotactile feedback for brain-computer interface operation. Comput Intell Neurosci. 2007:48937.
65. Muller-Putz GR, Scherer R, Neuper C, Pfurtscheller G. Steady-state somatosensory evoked potentials: suitable brain signals for brain-computer interfaces? IEEE Trans Neural Syst Rehabil Eng. 2006;14(1):30-37.
66. Neuper C, Muller GR, Kubler A, Birbaumer N, Pfurtscheller G. Clinical application of an EEG-based brain-computer interface: a case study in a patient with severe motor impairment. Clin Neurophysiol. 2003;114(3):399-409. (Pubitemid 36561109)
67. Vaughan TM, Sellers EW, Wolpaw JR. Clinical evaluation of BCIs. In: Wolpaw JR, Wolpaw EW, eds. Brain-Computer Interfaces: Principles and Practice. New York, NY: Oxford University Press; 2012.
68. Daly JJ, Wolpaw JR. Brain-computer interfaces in neurological rehabilitation. Lancet Neurol. 2008;7(11):1032-1043.
69. Leuthardt EC, Schalk G, Roland J, Rouse A, Moran DW. Evolution of brain-computer interfaces: going beyond classic motor physiology. Neurosurg Focus. 2009;27(1):E4.
70. Murase N, Duque J, Mazzocchio R, Cohen LG. Influence of interhemispheric interactions on motor function in chronic stroke. Ann Neurol. 2004;55(3):400-409. (Pubitemid 38269592)
71. Daly JJ, Fang Y, Perepezko EM, Siemionow V, Yue GH. Prolonged cognitive planning time, elevated cognitive effort, and relationship to coordination and motor control following stroke. IEEE Trans Neural Syst Rehabil Eng. 2006;14(2):168-171. (Pubitemid 44150233)
72. Enzinger C, Ropele S, Fazekas F, et al. Brain motor system function in a patient with complete spinal cord injury following extensive brain-computer interface training. Exp Brain Res. 2008;190(2):215-223.
73. Daly JJ, Cheng RC, Hrovat K, Litinas KH, Rogers JM, Dohring ME. Development and testing of non-invasive BCI + FES/robot system for use in motor re-learning after stroke. Proc 13th International Functional Electrical Stimulation Society. 2008:166-168.
74. Hermes D, Miller KJ, Vansteensel MJ, Aarnoutse EJ, Leijten FS, Ramsey NF. Neurophysiologic correlates of fMRI in human motor cortex. Hum Brain Mapp. 2011.
75. Lachaux JP, Fonlupt P, Kahane P, et al. Relationship between task-related gamma oscillations and BOLD signal: new insights from combined fMRI and intracranial EEG. Hum Brain Mapp. 2007;28(12):1368-1375. (Pubitemid 350234188)
76. Manning JR, Jacobs J, Fried I, Kahana MJ. Broadband shifts in local field potential power spectra are correlated with single-neuron spiking in humans. J Neurosci. 2009;29(43):13613-13620.
77. Miller KJ. Broadband spectral change: evidence for a macroscale correlate of population firing rate? J Neurosci. 2010;30(19):6477-6479.
78. Niessing J, Ebisch B, Schmidt KE, Niessing M, Singer W, Galuske RA. Hemodynamic signals correlate tightly with synchronized gamma oscillations. Science. 2005;309(5736):948-951. (Pubitemid 41099934)
79. Ray S, Crone NE, Niebur E, Franaszczuk PJ, Hsiao SS. Neural correlates of high-gamma oscillations (60-200 Hz) in macaque local field potentials and their potential implications in electrocorticography. J Neurosci. 2008;28(45):11526-11536.
80. Acharya S, Fifer MS, Benz HL, Crone NE, Thakor NV. Electrocorticographic amplitude predicts finger positions during slow grasping motions of the hand. J Neural Eng. 2010;7(4):046002.
81. Kubanek J, Miller KJ, Ojemann JG, Wolpaw JR, Schalk G. Decoding flexion of individual fingers using electrocorticographic signals in humans. J Neural Eng. 2009;6(6):066001.
82. Miller KJ, Zanos S, Fetz EE, der Nijs M, Ojemann JG. Decoupling the cortical power spectrum reveals real-time representation of individual finger movements in humans. J Neurosci. 2009;29(10):3132-3137.
83. Scherer R, Zanos SP, Miller KJ, Rao RP, Ojemann JG. Classification of contralateral and ipsilateral finger movements for electrocorticographic brain-computer interfaces. Neurosurg Focus. 2009;27(1):E12.
84. Gunduz A, Sanchez JC, Carney PR, Principe JC. Mapping broadband electrocorticographic recordings to two-dimensional hand trajectories in humans: motor control features. Neural Netw. 2009;22(9):1257-1270.
85. Schalk G, Kubanek J, Miller KJ, et al. Decoding two-dimensional movement trajectories using electrocorticographic signals in humans. J Neural Eng. 2007;4(3):264-275.
86. Pistohl T, Ball T, Schulze-Bonhage A, Aertsen A, Mehring C. Prediction of arm movement trajectories from ECoG-recordings in humans. J Neurosci Methods. 2008;167(1):105-114. (Pubitemid 350180091)
87. Felton EA, Wilson JA, Williams JC, Garell PC. Electrocorticographically controlled brain-computer interfaces using motor and sensory imagery in patients with temporary subdural electrode implants: report of four cases. J Neurosurg. 2007;106(3):495-500. (Pubitemid 46354307)
88. Leuthardt EC, Schalk G, Wolpaw JR, Ojemann JG, Moran DW. A brain-computer interface using electrocorticographic signals in humans. J Neural Eng. 2004(2);1:63-71. (Pubitemid 41079659)
89. Ramsey NF, van de Heuvel MP, Kho KH, Leijten FS. Towards human BCI applications based on cognitive brain systems: an investigation of neural signals recorded from the dorsolateral prefrontal cortex. IEEE Trans Neural Syst Rehabil Eng. 2006;14(2):214-217. (Pubitemid 44150245)
90. Schalk G, Miller KJ, Anderson NR, et al. Two-dimensional movement control using electrocorticographic signals in humans. J Neural Eng. 2008;5(1):75-84. (Pubitemid 351366605)
91. Wilson JA, Felton EA, Garell PC, Schalk G, Williams JC. ECoG factors underlying multimodal control of a brain-computer interface. IEEE Trans Neural Syst Rehabil Eng. 2006;14(2):246-250. (Pubitemid 44150253)
92. Brunner P, Ritaccio AL, Emrich JF, Bischof H, Schalk G. Rapid communication with a "P300" matrix speller using electrocorticographic signals (ECoG). Front Neurosci. 2011;5:5.
93. Hinterberger T, Widman G, Lal TN, et al. Voluntary brain regulation and communication with electrocorticogram signals. Epilepsy Behav. 2008;13(2):300-306.
94. Yanagisawa T, Hirata M, Saitoh Y, et al. Real-time control of a prosthetic hand using human electrocorticography signals. J Neurosurg. 2011;114(6):1715-1722.
95. Leuthardt EC, Gaona C, Sharma M, et al. Using the electrocorticographic speech network to control a brain-computer interface in humans. J Neural Eng. 2011;8(3):036004.
96. Canolty T, Soltani M, Dalal SS, et al. Spatiotemporal dynamics of word processing in the human brain. Front Neurosci. 2007;1(1):185-196.
97. Pei X, Leuthardt EC, Gaona CM, Brunner P, Wolpaw JR, Schalk G. Spatiotemporal dynamics of electrocorticographic high gamma activity during overt and covert word repetition. Neuroimage. 2011;54(4):2960-2972.
98. Leuthardt EC, Miller KJ, Schalk G, Rao RP, Ojemann JG. Electrocorticography-based brain computer interface - the Seattle experience. IEEE Trans Neural Syst Rehabil Eng. 2006;14(2):194-198. (Pubitemid 44150240)
99. Blakely T, Miller KJ, Zanos SP, Rao RP, Ojemann JG. Robust, long-term control of an electrocorticographic brain-computer interface with fixed parameters. Neurosurg Focus. 2009;27(1):E13.
100. Miller KJ, Schalk G, Fetz EE, den Nijs M, Ojemann JG, Rao P. Cortical activity during motor execution, motor imagery, and imagery-based online feedback. Proc Natl Acad Sci U S A. 2010;107(9):4430-4435.
101. Chao ZC, Nagasaka Y, Fujii N. Long-term asynchronous decoding of arm motion using electrocorticographic signals in monkeys. Front Neuroeng. 2010;3:3.
102. Schalk G. Can electrocorticography (ECoG) support robust and powerful brain-computer interfaces? Front Neuroeng. 2010;3:9.
103. Simeral JD, Kim SP, Black MJ, Donoghue JP, Hochberg LR. Neural control of cursor trajectory and click by a human with tetraplegia 1000 days after implant of an intracortical microelectrode array. J Neural Eng. 2011;8(2):025027.
104. Pohlmeyer EA, Oby ER, Perreault EJ, et al. Toward the restoration of hand use to a paralyzed monkey: brain-controlled functional electrical stimulation of forearm muscles. PLoS One. 2009;4(6):e5924.
105. Kennedy PR, Bakay RA, Moore MM, Adams K, Goldwaithe J. Direct control of a computer from the human central nervous system. IEEE Trans Rehabil Eng. 2000;8(2):198-202. (Pubitemid 30437013)
106. Kennedy PR, Bakay RA. Restoration of neural output from a paralyzed patient by a direct brain connection. Neuroreport. 1998;9(8):1707-1711. (Pubitemid 28289171)
107. Bartels J, Andreasen D, Ehirim P, et al. Neurotrophic electrode: method of assembly and implantation into human motor speech cortex. J Neurosci Methods. 2008;174(2):168-176.
108. Guenther FH, Brumberg JS, Wright EJ, et al. A wireless brain-machine interface for real-time speech synthesis. PLoS One. 2009;4(12):e8218.
109. Chapin JK, Moxon KA, Markowitz RS, Nicolelis MA. Real-time control of a robot arm using simultaneously recorded neurons in the motor cortex. Nat Neurosci. 1999;2:664-670. (Pubitemid 30491219)
110. Ganguly K, Carmena JM. Emergence of a stable cortical map for neuroprosthetic control. PLoS Biol. 2009;7(7):e1000153.
111. Musallam S, Corneil BD, Greger B, Scherberger H, Andersen RA. Cognitive control signals for neural prosthetics. Science. 2004;305(5681):258-262. (Pubitemid 38886742)
112. Santhanam G, Ryu SI, Yu BM, Afshar A, Shenoy KV. A high-performance brain-computer interface. Nature. 2006;442(7099):195-198. (Pubitemid 44086565)
113. Taylor DM, Tillery SI, Schwartz AB. Direct cortical control of 3D neuroprosthetic devices. Science. 2002;296(5574):1829-1832. (Pubitemid 34596262)
114. Velliste M, Perel S, Spalding MC, Whitford AS, Schwartz AB. Cortical control of a prosthetic arm for self-feeding. Nature. 2008;453(7198):1098-1101. (Pubitemid 351871735)
115. OCZ Technology Web site. http://gear.ocztechnology.com/products/ description/OCZ-Neural-Impulse-Actuator/index.html. Accessed September 5, 2011.
116. Brainfingers Web site. http://www.brainfingers.com/. Accessed September 5, 2011.
117. Emotiv Web site. http://www.emotiv.com/. Accessed September 5, 2011.
118. NeuroSky, Inc Web site. http://www.neurosky.com/. Accessed September 5, 2011.
119. Mattel Mind Flex Web site. http://shop.mattel.com/product/index.jsp? productId=11695206. Accessed January 27, 2012.
120. Uncle Milton Force Trainer Web site. http://unclemilton.com/star-wars- science/. Accessed September 5, 2011.
121. BrainMaster Technologies, Inc Web site. http://www.brainmaster.com/. Accessed September 5, 2011.
122. EEG Info Web site. http://www.eeginfo.com/. Accessed September 5, 2011.
123. EEG Spectrum International Web site. http://www.eegspectrum.com/. Accessed September 5, 2011.
124. Interactive Productline Mindball Web site. http://www.mindball.se/. Accessed September 5, 2011.
125. Guger Technologies Web site. http://www.gtec.at/. Accessed September 5, 2011.
126. Wolpaw JR. Brain-computer interface research comes of age: traditional assumptions meet emerging realities. J Mot Behav. 2010;42(6):351-353.