Closed loop brain machine interface

• US 20030093129A1
• Filed: 10/29/2001
• Published: 05/15/2003
• Est. Priority Date: 10/29/2001
• Status: Active Grant

• Current Assignee: Duke University
• Original Assignee: Duke University
• Inventors: Wessberg, Johan, Nicolelis, Miguel A.L., Chapin, John K.
• Granted Patent: US 7,209,788 B2
• Time in Patent Office: Days
• US Class Current: 607/45
• CPC Class Codes: A61B 2503/40 Animals
• CPC Class Codes: A61B 2503/42 for laboratory research
• CPC Class Codes: A61B 2562/046 in a matrix array
• CPC Class Codes: A61B 5/1114 Tracking parts of the body
• CPC Class Codes: A61B 5/291 for electroencephalography [EEG]
• CPC Class Codes: A61B 5/293 Invasive
• CPC Class Codes: A61B 5/375 using biofeedback
• CPC Class Codes: A61B 5/6868 Brain
• CPC Class Codes: A61B 5/72 Signal processing specially adapted for physiological signals or for diagnostic purposes character recognition, recognising digital ink, document-oriented image-based pattern recognition G06V30/00; recognition or understanding of postal images G06V30/424
• CPC Class Codes: A61B 5/7221 Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take precedence
• CPC Class Codes: A61B 5/7455 characterised by tactile indication, e.g. vibration or electrical stimulation
• CPC Class Codes: A61F 2/72 Bioelectric control, e.g. myoelectric
• CPC Class Codes: A61F 2002/704 computer-controlled, e.g. robotic control
• CPC Class Codes: G06F 3/015 Input arrangements based on nervous system activity detection, e.g. brain waves [EEG] detection, electromyograms [EMG] detection, electrodermal response detection
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: Y10S 128/905 Feedback to patient of biological signal other than brain electric signal

Abstract

A closed loop brain-machine interface is disclosed. The closed loop brain-machine interface translates one or more neural signals into a movement, or a series of movements, performed by a machine. The close-loop brain-machine interface also provides sensory feedback to the subject. Methods of employing the closed loop brain-machine interface are also disclosed.

Claims

1. A real time closed loop brain-machine interface comprising:

(a) a plurality of electrodes adapted to be chronically implanted in the nervous system of a subject and to acquire extracellular electrical signals from a population of single neurons;

(b) a signal processing mechanism adapted to communicate with the plurality of electrodes and adapted to form extracted motor commands from the extracellular electrical signals; and

(c) an actuator adapted to communicate with the signal processing mechanism and to respond to the extracted motor commands by effecting a movement, and to provide sensory feedback to the subject.

2. The real time closed loop brain-machine interface of claim 1, wherein the plurality of electrodes comprises one or more microwires.

3. The real time closed loop brain-machine interface of claim 2, wherein the microwires comprise a material selected from the group consisting of stainless steel, platinum, and tungsten.

4. The real time closed loop brain-machine interface of claim 3, wherein the diameter of the one or more microwires is about 50 μ

m.

5. The real time closed loop brain-machine interface of claim 3, wherein the microwires are TEFLON®

coated.

6. The real time closed loop brain-machine interface of claim 3, wherein the one or more microwires are oriented in a definite spatial relationship relative to one another to thereby form a microwire array.

7. The real time closed loop brain-machine interface of claim 6, wherein the diameter of the one or more microwires is about 25 to 50 μ

m.

8. The real time closed loop brain-machine interface of claim 6, wherein the microwires are TEFLON®

coated.

9. The real time closed loop brain-machine interface of claim 6, wherein the microwire array comprises about 16 to 128 microwires.

10. The real time closed loop brain-machine interface of claim 2, wherein the one or more microwires are oriented in a definite spatial relationship relative to one another to thereby form a microwire bundle.

11. The real time closed loop brain-machine interface of claim 10, wherein the microwires comprise a material selected from the group consisting of stainless steel, platinum and tungsten.

12. The real time closed loop brain-machine interface of claim 10, wherein the diameter of the one or more microwires is about 25 to 50 μ

m.

13. The real time closed loop brain-machine interface of claim 10, wherein the microwires are TEFLON®

coated.

14. The real time closed loop brain-machine interface of claim 10, wherein the microwires have different lengths.

15. The real time closed loop brain-machine interface of claim 14, wherein the difference in length between a first wire tip and a second wire tip is about 150 to 300 μ

m.

16. The real time closed loop brain-machine interface of claim 1, wherein the signal processing mechanism comprises:

(a) one or more neurochips adapted to be chronically implanted in the body of a subject in communication with the plurality of electrodes;

(b) a data acquisition module in communication with the one or more neurochips;

(c) a motor command extraction module in communication with the data acquisition module; and

(d) a power supply for relaying power to the one or more neurochips and transmitting signals received at the one or more neurochips to the data acquisition module.

17. The real time closed loop brain-machine interface of claim 16, wherein the one or more neurochips are sealed with an insulating material, thereby preventing contact with blood or tissue.

18. The real time closed loop brain-machine interface of claim 17, wherein the insulating material is aluminum trioxide.

19. The real time closed loop brain-machine interface of claim 16, wherein the one or more neurochips are adapted to amplify the extracellular electrical signals received by the one or more neurochips.

20. The real time closed loop brain-machine interface of claim 16, wherein the one or more neurochips are adapted to filter extracellular electrical signals received by the one or more neurochips.

21. The real time closed loop brain-machine interface of claim 16, wherein the one or more neurochips are adapted to multiplex neural signals received by the one or more neurochips.

22. The real time closed loop brain-machine interface of claim 16, wherein the data acquisition module comprises a many neuron acquisition processor.

23. The real time closed loop brain-machine interface of claim 16, wherein the data acquisition module comprises one or more timing boards.

24. The real time closed loop brain-machine interface of claim 16, wherein the data acquisition module comprises one or more digital signal processors.

25. The real time closed loop brain-machine interface of claim 16, wherein the data acquisition module comprises one or more spike discrimination programs.

26. The real time closed loop brain-machine interface of claim 16, wherein the data acquisition module is adapted to store data received from the one or more neurochips.

27. The real time closed loop brain-machine interface of claim 16, wherein communication between the one or more neurochips and the data acquisition module is wireless.

28. The real time closed loop brain-machine interface of claim 16, wherein communication between the one or more neurochips and the data acquisition module is through a cable.

29. The real time closed loop brain-machine interface of claim 16, wherein the motor command extraction module comprises one or more computational algorithms running on one or more microchips.

30. The real time closed loop brain-machine interface of claim 29, wherein the one or more computational algorithms is a linear model.

31. The real time closed loop brain-machine interface of claim 29, wherein the one or more computational algorithms is an artificial neural network.

32. The real time closed loop brain-machine interface of claim 16, wherein the power supply comprises a lithium battery.

33. The real time closed loop brain-machine interface of claim 1, wherein the actuator comprises a prosthetic limb.

34. The real time closed loop brain-machine interface of claim 1, wherein the actuator comprises a device adapted to provide electrical stimulation of one or more muscles.

35. A real time closed loop brain-machine interface for restoring voluntary motor control and sensory feedback to a subject that has lost a degree of voluntary motor control and sensory feedback comprising:

(a) an implantable microwire electrode array adapted to acquire one or more brain-derived neural signals;

(b) an implantable neurochip adapted to communicate with the implantable microwire array and to filter and amplify the one or more neural signals;

(c) a motor command extraction microchip adapted to communicate with the implantable neurochip and embodying one or more motor command extraction algorithms, the microchip and the algorithms adapted to extract motor commands from the brain-derived neural signals;

(d) an actuator adapted to communicate with the motor command extraction microchip and to move in response to the motor commands and to acquire sensory feedback information during and subsequent to a movement;

(e) a sensory feedback microchip embodying one or more sensory feedback information interpretation algorithms adapted to communicate with the actuator, the sensory feedback microchip adapted to form interpreted sensory feedback information;

(f) a structure adapted to communicate with the sensory feedback microchip and to deliver interpreted sensory feedback information to the subject; and

(g) one or more power sources adapted to provide power, as necessary, to one or more of the group comprising;

the implantable neurochip;

the motor command extraction microchip;

the actuator;

the sensory feedback microchip; and

the structure adapted to relay interpreted sensory feedback information to the subject.

36. The real time closed loop brain-machine interface of claim 35, wherein the microwire electrode array comprises TEFLON®

coated stainless steel microwires.

37. The real time closed loop brain-machine interface of claim 35, wherein the one or more motor command extraction algorithms comprise a linear model.

38. The real time closed loop brain-machine interface of claim 35, wherein the one or more motor command extraction algorithms comprise an artificial neural network.

39. The real time closed loop brain-machine interface of claim 35, wherein the motor command extraction microchip is implantable.

40. The real time closed loop brain-machine interface of claim 35, wherein the communication between the implantable neurochip and the motor command extraction microchip is wireless.

41. The real time closed loop brain-machine interface of claim 35, wherein the actuator comprises a prosthetic limb.

42. The real time closed loop brain-machine interface of claim 35, wherein the actuator comprises a device adapted to provide electrical stimulation of one or more muscles.

43. The real time closed loop brain-machine interface of claim 35, wherein the communication between the actuator and the motor command extraction microchip is wireless.

44. The real time closed loop brain-machine interface of claim 35, wherein the one or more sensory feedback interpretation algorithms is selected from the group consisting of linear and ANN algorithms.

45. The real time closed loop brain-machine interface of claim 35, wherein the sensory feedback information is provided to the subject in the form of a physical stimulus delivered to the body of the subject.

46. The real time closed loop brain-machine interface of claim 35, wherein the sensory feedback information is provided to the subject in the form of a pattern of electrical microstimulation delivered to the nervous system of the subject.

47. A method of controlling an actuator adapted to provide sensory feedback to a subject by neural signals, the method comprising:

(a) collecting a neural signal directly from the nervous system of a subject;

(b) processing the neural signal to form a processed neural signal;

(c) extracting a motor command from the processed neural signal to form an extracted motor command;

(e) transmitting the extracted motor command to an actuator, whereby the actuator effects a movement;

(f) acquiring sensory feedback information from the actuator;

(g) interpreting the sensory feedback information to form interpreted sensory feedback;

information; and

(h) relaying the interpreted sensory feedback information back to the subject.

48. The method of claim 47, wherein the neural signal is an electrical signal.

49. The method of claim 47, wherein the neural signal is acquired via plurality of electrodes comprising one or more microwires.

50. The method of claim 49, wherein the microwires comprise a material selected from the group consisting of stainless steel, platinum and tungsten.

51. The method of claim 49, wherein the diameter of the one or more microwires is about 50 μ

m.

52. The method of claim 49, wherein the microwires are TEFLON®

coated.

53. The method of claim 49, wherein the one or more microwires are oriented in a definite spatial relationship relative to one another to thereby form a microwire array.

54. The method of claim 53, wherein the microwires comprise a material selected from the group consisting of stainless steel, platinum and tungsten.

55. The method of claim 53, wherein the diameter of the one or more microwires is about 25 to 50 μ

m.

56. The method of claim 53, wherein the microwires are TEFLON®

coated.

57. The method of claim 53, wherein the microwire array comprises about 16 to 128 microwires.

58. The method of claim 49, wherein the one or more microwires are oriented in a definite spatial relationship relative to one another to thereby form a microwire bundle.

59. The method of claim 58, wherein the microwires comprise a material selected from the group consisting of stainless steel, platinum and tungsten.

60. The method of claim 58, wherein the diameter of the one or more microwires is about 25 to 50 μ

m.

61. The method of claim 58, wherein the microwires are TEFLON®

coated.

62. The method of claim 58, wherein the microwires have different lengths.

63. The method of claim 58, wherein the difference in length between a first wire tip and a second wire tip is about 150 to 300 μ

m.

64. The method of claim 47, wherein the collecting is performed in real time.

65. The method of claim 47, wherein the processing comprises:

(a) amplifying the one or more neural signals to form amplified neural signals;

(b) filtering the amplified neural signals to form filtered neural signals; and

(c) performing a spike detection analysis on the filtered neural signals.

66. The method of claim 47, wherein the processing is performed in real time.

67. The method of claim 47, wherein the extracting comprises applying a linear model to the processed neural signals.

68. The method of claim 48, wherein the extracting comprises applying an artificial neural network to the processed neural signals.

69. The method of claim 47, wherein the extracting is performed in real time.

70. The method of claim 47, wherein the transmitting comprises conveying the extracted motor commands wirelessly.

71. The method of claim 47 wherein the transmitting comprises conveying the extracted motor commands over a cable.

72. The method of claim 47, wherein the transmitting is performed in real time.

73. The method of claim 47, wherein the sensory information is selected from the group consisting of tactile information, temperature information and visual information.

74. The method of claim 47, wherein the sensory feedback information is acquired in real time.

75. The method of claim 47, wherein the sensory feedback information is relayed to the subject wirelessly.

76. The method of claim 47, wherein the sensory feedback information is relayed to the subject through a cable.

77. The method of claim 47, further comprising imparting the sensory feedback information to the subject.

78. The method of claim 77, wherein the imparting is by a mechanical stimulus delivered to the body of the subject.

79. The method of claim 77, wherein the imparting is by a pattern of electrical stimulation delivered to the nervous system of the subject.

80. A method of imparting voluntary motor control and sensory feedback to a subject that has lost a degree of voluntary motor control and sensory feedback, the method comprising:

(a) implanting a neural signal acquisition apparatus in the tissue of a subject'"'"'s central nervous system;

(b) fitting the subject with an actuator adapted to respond to neural signals with movement and to acquire sensory feedback;

(c) collecting one or more neural signals;

(d) extracting one or more motor commands from the acquired neural signals to form extracted motor commands;

(e) transmitting the extracted motor commands to the actuator;

(f) effecting a movement corresponding to the extracted motor commands;

(g) acquiring sensory feedback information via the actuator;

(h) interpreting the sensory feedback information to form interpreted sensory feedback information; and

(i) relaying the interpreted sensory feedback information to the subject, whereby voluntary motor control and sensory feedback is imparted to a subject that has lost a degree of voluntary motor control and sensory feedback.

81. The method of claim 80, wherein the neural signal acquisition apparatus comprises:

(a) a plurality of electrodes; and

(b) a neurochip adapted to amplify and filter neural signals the neurochip adapted to communicate with the plurality of electrodes.

82. The method of claim 81, wherein the plurality of electrodes comprises one or more microwire electrode arrays

83. The method of claim 81, wherein the plurality of electrodes comprises one or more microwire bundles.

84. The method of claim 80, wherein the neural signals comprise electrical signals.

85. The method of claim 80, wherein the collecting is performed in real time.

86. The method of claim 80, wherein the actuator comprises a prosthetic limb.

87. The method of claim 80, wherein the actuator comprises a device adapted to provide electrical stimulation of one or more muscles.

88. The method of claim 80, wherein the fitting comprises interfacing the actuator with the central nervous system of the subject.

89. The method of claim 80, wherein the extracting comprises passing the one or more acquired neural signals through a linear model.

90. The method of claim 80, wherein the extracting comprises passing the one or more acquired neural signals through an artificial neural network.

91. The method of claim 80, wherein the transmitting comprises conveying the extracted motor commands wirelessly.

92. The method of claim 80, wherein the transmitting comprises conveying the extracted motor commands over a cable.

93. The method of claim 80, wherein the effected movement comprises a motion in three-dimensions.

94. The method of claim 80, wherein the movement effecting is performed in real time.

95. The method of claim 80, wherein the sensory feedback information comprises information selected from the group consisting of tactile information, temperature information and visual information.

96. The method of claim 80, wherein the acquiring is performed by one or more sensor mechanisms disposed on the actuator.

97. The method of claim 96, wherein the one or more sensor mechanisms comprise one or more devices adapted to provide one or visual and tactile feedback information.

98. The method of claim 80, wherein the interpreting comprises performing one of a linear algorithm and an ANN algorithm.

99. The method of claim 80, wherein the interpreting is performed by one or more algorithms embodied on an implanted microchip.

100. The method of claim 80, wherein the interpreting is performed by one or more algorithms embodied on the actuator.

101. The method of claim 80, wherein the interpreting is performed in real time.

102. The method of claim 80, wherein the relaying comprises conveying the interpreted sensory feedback information wirelessly.

103. The method of claim 80, wherein the relaying comprises conveying the interpreted sensory feedback information through a cable.

104. The method of claim 80, wherein the relaying is performed in real time.

105. The method of claim 80, wherein the sensory feedback information is relayed to the subject in the form of a physical stimulus delivered to the body of the subject.

106. The method of claim 80, wherein the sensory feedback information is relayed to the subject in the form of a stimulus delivered to the nervous system of the subject.

107. The method of claim 106, wherein the stimulus is an electrical stimulus.

108. The method of claim 80, wherein the steps (a) through (i) are performed in real time.