Subthreshold stimulation of a cochlea

• US 8,538,541 B2
• Filed: 11/11/2002
• Issued: 09/17/2013
• Est. Priority Date: 11/09/2001
• Status: Expired due to Fees

• Current Assignee: Cochlear Limited
• Original Assignee: Cochlear Limited
• Inventors: Milojevic, Dusan, Parker, John
• Primary Examiner(s): MANUEL, GEORGE C
• Application Number:
  US10/494,995
• Publication Number:
  US 20050033377A1
• Time in Patent Office: 3,963 Days
• Field of Search: 607/57
• US Class Current: 607/57
• CPC Class Codes: A61M 2205/05 combined with other kinds of therapy
• CPC Class Codes: A61M 2210/0662 Ears
• CPC Class Codes: A61M 5/14276 specially adapted for implantation
• CPC Class Codes: A61N 1/00 Electrotherapy; Circuits therefor A61N2/00 takes precedence; irradiation apparatus A61N5/00
• CPC Class Codes: A61N 1/36038 Cochlear stimulation
• CPC Class Codes: A61N 1/36082 Cognitive or psychiatric applications, e.g. dementia or Alzheimer's disease

Abstract

An implantable apparatus, such as a cochlear implant, for delivering electrical plasticity informative stimuli to a neural network of an implantee. The apparatus comprises a stimulator device (40) that generates stimulation signals, and an electrode array (20) that receives the stimulation signals and delivers the stimuli to the neural network of the implantee in response to the signals. The stimuli delivered to the implantee facilitates and/or controls the production and/or release of naturally occurring agents into the neural network to influence the functionality thereof.

Claims

1. An apparatus for delivering electrical stimuli to an auditory system of an implantee, comprising:

an stimulator configured to generate stimulation signals having the stimuli encoded therein; and

at least one electrode member configured to deliver the stimulation signals to the auditory system;

wherein the stimuli comprises plasticity informative stimuli having a magnitude below an auditory perception threshold of the implantee, the plasticity informative stimuli configured to facilitate the production and/or release of naturally occurring neurotrophic agents into the auditory system.

2. An apparatus of claim 1 wherein the apparatus is configured to modify the functionality of the auditory system in a predetermined manner.

3. An apparatus of claim 1 wherein the apparatus is configured to deliver the stimuli to at least one of the cochlea, inferior colliculus, the Subthalamic Nucleus (STN), the Globus Pallidus (GPi), and the Thalamus of the implantee.

4. An apparatus of claim 1 wherein the apparatus is a component of a hearing prosthesis that is also adapted to deliver auditory informative stimuli having a magnitude that is about at or above the auditory perception threshold of the implantee to the auditory system of the implantee.

5. An apparatus of claim 4 wherein the hearing prosthesis is a cochlear implant.

6. An apparatus of claim 4 wherein the hearing prosthesis is a hearing aid.

7. An apparatus of claim 4 wherein the prosthesis comprises an electrode array that is implantable in the cochlea of the implantee and is adapted to deliver said plasticity informative stimuli and auditory informative stimuli to the cochlea of the implantee.

8. An apparatus of claim 4 wherein the prosthesis comprises a first electrode array configured to deliver said plasticity informative stimuli and a second electrode array configured to deliver said auditory informative stimuli to the auditory system of the implantee.

9. An apparatus of claim 8 wherein the first electrode array is insertable into the auditory system at a location different from that of the second electrode array.

10. An apparatus of claim 8 wherein both said first and said second electrode arrays comprise an elongate carrier member having a plurality of electrodes mounted thereon.

11. An apparatus of claim 10 wherein the stimulator is electrically connected to each of the elongate carrier members via an electrical lead, the lead including one or more wires extending from each electrode of each elongate member.

12. An apparatus of claim 4 wherein the apparatus is implantable and further wherein the hearing prosthesis comprises an external component that is configured to operate in conjunction with the implantable apparatus, the external component comprising:

a microphone configured to detect sounds and further configured to output acoustic signals representative of said detected sounds; and

a processor configured to receive said acoustic signals from the microphone and to convert the signals into stimulation signals representative of the detected sounds, and further configured to encode said stimuli into said stimulation signals, deliver said stimulation signals transcutaneously to the stimulator.

13. An apparatus of claim 12 wherein the external component comprises a controller configured to control the output of the stimulator.

14. An apparatus of claim 12 wherein the external component further comprises a power source.

15. An apparatus of claim 1 wherein the apparatus is configured to deliver said plasticity informative stimuli to the cochlea of the implantee and is configured to operate in conjunction with a cochlear implant device adapted to deliver said auditory informative stimuli to the same cochlea of the implantee.

16. An apparatus of claim 1 wherein the apparatus is configured to operate in conjunction with an external component, the external component comprising a controller configured to control the output of the plasticity informative stimuli from the stimulator.

17. An apparatus of claim 16 wherein the external component further comprises a power source.

18. An apparatus of claim 1 wherein the stimulator is housed in a housing that is totally implantable within the implantee.

19. An apparatus of claim 18 wherein the housing is further configured to house a power source configured to provide the apparatus with at least sufficient power to deliver plasticity informative stimuli.

20. An apparatus of claim 1 wherein said at least one electrode member is part of an electrode array that is implantable in the auditory system of the implantee.

21. An apparatus of claim 20 wherein said electrode array comprises an elongate electrode carrier member having a plurality of electrodes mounted thereon.

22. An apparatus of claim 21 wherein the stimulator is electrically connected to the elongate member by way of an electrical lead, the lead comprising one or more wires extending from each electrode of the array mounted on the elongate member.

23. An apparatus of claim 1 wherein said plasticity informative stimuli is configured to be delivered in a duty cycle comprising a period of time (t1) of active stimulus and a period of time (t2) of no stimulus.

24. An apparatus of claim 23 wherein the apparatus has at least two electrode members and the plasticity informative stimuli is configured to be delivered simultaneously or sequentially by said at least two electrode members.

25. An apparatus of claim 24 wherein the beginning of the active part of the duty cycle for an electrode member is configured to occur with a delay with respect to the commencement of the duty cycle of at least one adjacent electrode member, but before the active part of the duty cycle of said at least one adjacent electrode member is finished.

26. An apparatus of claim 23 wherein the apparatus has at least two electrode members and wherein the active part of the duty cycle for each active electrode is configured to occur simultaneously.

27. An apparatus of claim 23 wherein the apparatus has at least two electrode members and wherein at any given time only one stimulating electrode is active.

28. An apparatus of claim 27 wherein the active part of each duty cycle is configured to be delivered sequentially by said at least two electrode members.

29. An apparatus of claim 1 wherein the apparatus is configured to measure the activity of one or more of the electrode members delivering auditory informative stimuli over a period of time of use.

30. An apparatus of claim 29 wherein the plasticity informative stimuli configured to be delivered by each electrode member is varied depending on the measure of activity determined for that electrode over said period of time.

31. An apparatus of claim 1 wherein the stimulator comprises a processor configured to process a set of instructions stored on the processor in the form of software.

32. An apparatus of claim 1 wherein said naturally occurring neurotrophic agents comprise one or more neurotrophic factors selected from the group comprising Brain Derived Neurotrophic Factor (BDNF), NGF, NT-3, NT-4/5, NT-6, LIF, GDNF, CNTF, and IGF-I.

33. An apparatus of claim 1 wherein said naturally occurring neurotrophic agents comprise neurotrophic factors that increase the survival of spiral ganglion cells.

34. An apparatus of claim 1 wherein said stimuli is configured to elicit outgrowth of spiral ganglion cells towards said at least one electrode member.

35. An apparatus of claim 1 wherein said stimuli is configured to be delivered at a frequency less than 5 kHz.

36. An apparatus of claim 1 wherein the apparatus is configured to deliver plasticity informative stimuli at times when the apparatus is not delivering auditory informative stimuli.

37. A method of delivering stimuli to an auditory system of an implantee, via an stimulator electrically coupled to at least one electrode member, wherein the electrode member is positioned to deliver the stimuli to the implantee, comprising:

generating stimulation signals having the stimuli to be delivered encoded therein; and

delivering said stimulation signals via at least one electrode member to the auditory system of the implantee;

wherein the stimuli comprises plasticity informative stimuli having a magnitude below an auditory perception threshold of the implantee and auditory informative stimuli, the plasticity informative stimuli configured to facilitate the production and/or release of naturally occurring neurotrophic agents into the auditory system.

38. A method of delivering stimuli to the auditory system of claim 37 wherein the stimuli is configured to modify the functionality of the auditory system in a predetermined desired manner.

39. A method of delivering stimuli to the auditory system of claim 37, further comprising:

positioning least one electrode member in a cochlea of the implantee prior to said delivering stimulation signals.

40. A method of delivering stimuli to the auditory system of claim 37 wherein said at least one electrode is adapted to deliver said plasticity informative stimuli and said auditory informative stimuli to the cochlea of the implantee.

41. An implantable apparatus for delivering electrical stimuli to an auditory system of an implantee, the apparatus comprising:

a stimulator configured to generate stimulation signals; and

an electrode array implantable in the auditory system, comprising at least one electrode member configured to deliver the stimulation signals to the auditory system;

wherein the stimuli comprises plasticity informative stimuli having a magnitude below a perception threshold of the implantee, the plasticity informative stimuli configured to facilitate the production and/or release of naturally occurring neurotrophic agents into the auditory system.

42. An implantable apparatus of claim 41 wherein the stimuli is configured to modify the functionality of the auditory system in a predetermined desired manner.

43. An implantable apparatus of claim 41 wherein the apparatus is configured to deliver the stimuli to at least one of the cochlea, inferior colliculus, the Subthalamic Nucleus (STN), the Globus Pallidus (GPi), and the Thalamus of the implantee.

44. An implantable apparatus of claim 41 wherein the perception threshold is an auditory perception threshold of the implantee.

45. An implantable apparatus of claim 41 wherein the apparatus is a component of a hearing prosthesis that is also adapted to deliver auditory informative stimuli having a magnitude that is about at or above the auditory perception threshold of the implantee to the auditory system of the implantee.

46. An implantable apparatus of claim 45 wherein the hearing prosthesis is a cochlear implant.

47. An implantable apparatus of claim 45 wherein the hearing prosthesis is a hearing aid.

48. An implantable apparatus of claim 45 wherein said electrode array is implantable in the cochlea of the implantee and is adapted to deliver said plasticity informative stimuli and said auditory informative stimuli to the cochlea of the implantee.

49. An implantable apparatus of claim 45 wherein the prosthesis comprises a first electrode array configured to deliver plasticity informative stimuli and a second electrode array configured to deliver auditory informative stimuli to the auditory system of the implantee.

50. An implantable apparatus of claim 49 wherein the first electrode array is insertable into the auditory system at a location different from that of the second electrode array.

51. An implantable apparatus of claim 44 wherein the apparatus is configured to deliver plasticity informative stimuli to the cochlea of the implantee and is configured to operate in conjunction with a cochlear implant device adapted to deliver auditory informative stimuli to the same cochlea of the implantee.

52. An implantable apparatus of claim 44 wherein the apparatus is configured to operate in conjunction with an external component, the external component comprising a controller that is configured to control the output of the plasticity informative stimuli from the stimulator.

53. An implantable apparatus of claim 44 wherein the stimulator is housed in a housing that is totally implantable within the implantee.

54. An implantable apparatus of claim 41 wherein the apparatus has at least two electrode members and the plasticity informative stimuli is configured to be delivered simultaneously or sequentially by said at least two electrode members.

55. An implantable apparatus of claim 41 wherein the apparatus has at least two electrode members and wherein the active part of the duty cycle for each active electrode is configured to occur simultaneously.

56. An implantable apparatus of claim 41 wherein the apparatus has at least two electrode members and wherein at any given time only one stimulating electrode is active.

57. An implantable apparatus of claim 41 wherein said naturally occurring neurotrophic agents comprise one or more neurotrophic factors selected from the group comprising Brain Derived Neurotrophic Factor (BDNF), NGF, NT-3, NT-4/5, NT-6, LIF, GDNF, CNTF, and IGF-I.

58. An implantable apparatus of claim 41 wherein said naturally occurring neurotrophic agents comprise neurotrophic factors that increase the survival of spiral ganglion cells.

59. An implantable apparatus of claim 41 wherein said stimuli is configured to elicit outgrowth of spiral ganglion cells towards said at least one electrode member.

60. An implantable apparatus of claim 41 wherein the apparatus is configured to deliver plasticity informative stimuli at times when the apparatus is not delivering auditory informative stimuli.

61. A method of delivering stimuli to an auditory system of an implantee via an electrode array having at least one electrode member, configured to deliver the stimuli to the implantee and positioned in a neural network, comprising:

generating stimulation signals having the stimuli to be delivered encoded therein; and

delivering said stimulation signals to said via at least one electrode member to the implantee;

wherein the stimuli includes plasticity informative stimuli having a magnitude below a perception threshold of the implantee, the plasticity informative stimuli configured to facilitate the production and/or release of naturally occurring neurotrophic agents into the neural network.

62. A method of delivering stimuli to the neural network of claim 61 wherein the stimuli is configured to modify the functionality of the neural network in a predetermined desired manner.

63. A method of delivering stimuli to the neural network of claim 61 wherein the stimuli is configured to be delivered to the auditory system of the implantee.

64. A method of delivering stimuli to the neural network of claim 61 wherein positioning an electrode array comprises positioning said electrode array in a cochlea of the implantee.

65. A method of delivering stimuli to the neural network of claim 61 wherein said at least one electrode is adapted to deliver plasticity informative stimuli and auditory informative stimuli to the cochlea of the implantee.

66. An implantable apparatus for delivering electrical stimuli to a neural network of an implantee, the apparatus comprising:

a stimulator configured to generate stimulation signals; and

at least one electrode member configured to receive the stimulation signals and configured to deliver the stimuli to the neural network in response to said signals;

wherein the stimuli includes plasticity informative stimuli having a magnitude below a perception threshold of the implantee, the plasticity informative stimuli facilitating the production and/or release of naturally occurring neurotrophic agents into the neural network, and

wherein said naturally occurring neurotrophic agents comprise one or more neurotrophic factors selected from the group comprising Brain Derived Neurotrophic Factor (BDNF), NGF, NT-3, NT-4/5, NT-6, LIF, GDNF, CNTF, and IGF-I.

67. An implantable apparatus of claim 66 wherein the apparatus is configured to deliver stimuli to the auditory system of the implantee.

68. An implantable apparatus of claim 67 wherein the perception threshold is an auditory perception threshold of the implantee.

69. An implantable apparatus of claim 68 wherein the apparatus is a component of a hearing prosthesis that is also adapted to deliver auditory informative stimuli having a magnitude that is about at or above the auditory perception threshold of the implantee to the auditory system of the implantee.

70. An implantable apparatus of claim 69 wherein the hearing prosthesis is a cochlear implant.

71. An implantable apparatus of claim 69 wherein the hearing prosthesis is a hearing aid.

72. An implantable apparatus of claim 69 wherein the prosthesis includes an electrode array that is implantable in the cochlea of the implantee and is adapted to deliver both plasticity informative stimuli and auditory informative stimuli to the cochlea of the implantee.

73. An implantable apparatus of claim 69 wherein the prosthesis comprises a first electrode array configured to deliver plasticity informative stimuli and a second electrode array configured to deliver auditory informative stimuli to the auditory system of the implantee.

74. An implantable apparatus of claim 68 wherein the apparatus delivers plasticity informative stimuli to the cochlea of the implantee and is configured to operate in conjunction with a cochlear implant device adapted to deliver auditory informative stimuli to the same cochlea of the implantee.

75. An implantable apparatus of claim 66 wherein the apparatus is configured to deliver the stimuli to at least one of the cochlea, inferior colliculus, the Subthalamic Nucleus (STN), the Globus Pallidus (GPi), and the Thalamus of the implantee.

76. An implantable apparatus of claim 75 wherein said naturally occurring neurotrophic agents comprise neurotrophic factors that increase the survival of spiral ganglion cells.

77. An implantable apparatus of claim 66 wherein the apparatus has at least two electrode members and the plasticity informative stimuli is configured to be delivered simultaneously or sequentially by said at least two electrode members.

78. An implantable apparatus of claim 66 wherein the apparatus has at least two electrode members and wherein at any given time only one stimulating electrode is active.

79. An implantable apparatus of claim 66 wherein said stimuli elicits outgrowth of spiral ganglion cells towards said at least one electrode member.

80. A method of delivering stimuli to an auditory system of an implantee, via an stimulator electrically coupled to at least one electrode member, wherein the electrode member is positioned to deliver the stimuli to the implantee, comprising the steps of:

generating stimulation signals having the stimuli to be delivered encoded therein; and

delivering said stimulation signals via at least one electrode member to the auditory system of the implantee;

wherein the stimuli includes plasticity informative stimuli having a magnitude below a perception threshold of the implantee, the plasticity informative stimuli facilitating the production and/or release of naturally occurring neurotrophic agents into the auditory system, wherein said naturally occurring neurotrophic agents comprise one or more neurotrophic factors selected from the group comprising Brain Derived Neurotrophic Factor (BDNF), NGF, NT-3, NT-4/5, NT-6, LIF, GDNF, CNTF, and IGF-I.

81. A method of delivering stimuli to the auditory system of claim 80 wherein the stimuli is configured to be delivered to the auditory system of the implantee.

82. A method of delivering stimuli to the auditory system of claim 80 wherein positioning at least one electrode member comprises positioning said at least one electrode member in a cochlea of the implantee.

83. A method of delivering stimuli to the auditory system of claim 80 wherein said at least one electrode is adapted to deliver plasticity informative stimuli and auditory informative stimuli to the cochlea of the implantee.

84. An implantable apparatus for delivering electrical stimuli to a neural network of an implantee, the apparatus comprising:

a stimulator that generates stimulation signals; and

at least one electrode member configured to receive the stimulation signals and configured to deliver the stimuli to the neural network in response to said signals;

wherein the stimuli includes plasticity informative stimuli having a magnitude below a perception threshold of the implantee, the plasticity informative stimuli facilitating the production and/or release of naturally occurring neurotrophic agents into the neural network, and

wherein said naturally occurring neurotrophic agents comprise neurotrophic factors that increase the survival of spiral ganglion cells.

85. An implantable apparatus of claim 84 wherein the apparatus delivers stimuli to the auditory system of the implantee.

86. An implantable apparatus of claim 85 wherein the perception threshold is an auditory perception threshold of the implantee.

87. An implantable apparatus of claim 86 wherein the apparatus is a component of a hearing prosthesis that is also adapted to deliver auditory informative stimuli having a magnitude that is about at or above the auditory perception threshold of the implantee to the auditory system of the implantee.

88. An implantable apparatus of claim 87 wherein the hearing prosthesis is a cochlear implant.

89. An implantable apparatus of claim 87 wherein the hearing prosthesis is a hearing aid.

90. An implantable apparatus of claim 86 wherein the apparatus delivers plasticity informative stimuli to the cochlea of the implantee and is configured to operate in conjunction with a cochlear implant device adapted to deliver auditory informative stimuli to the same cochlea of the implantee.

91. An implantable apparatus of claim 86 wherein the apparatus is configured to operate in conjunction with an external component, the external component comprising a controller that controls the output of the plasticity informative stimuli from the stimulator.

92. An implantable apparatus of claim 84 wherein the apparatus is configured to deliver the stimuli to at least one of the cochlea, inferior colliculus, the Subthalamic Nucleus (STN), the Globus Pallidus (GPi), and the Thalamus of the implantee.

93. An implantable apparatus of claim 84 wherein the apparatus has at least two electrode members and the plasticity informative stimuli is configured to be delivered simultaneously or sequentially by said at least two electrode members.

94. An implantable apparatus of claim 84 wherein the apparatus has at least two electrode members and wherein the active part of the duty cycle for each active electrode occurs simultaneously.

95. An implantable apparatus of claim 84 wherein the apparatus has at least two electrode members and wherein at any given time only one stimulating electrode is active.

96. An implantable apparatus of claim 84 wherein said naturally occurring neurotrophic agents comprise one or more neurotrophic factors selected from the group comprising Brain Derived Neurotrophic Factor (BDNF), NGF, NT-3, NT-4/5, NT-6, LIF, GDNF, CNTF, and IGF-I.

97. An implantable apparatus of claim 84 wherein said stimuli elicits outgrowth of spiral ganglion cells towards said at least one electrode member.

98. A method of delivering stimuli to an auditory system of an implantee, via an stimulator electrically coupled to at least one electrode member, wherein the electrode member is positioned to deliver the stimuli to the implantee, comprising the steps of:

generating stimulation signals having the stimuli to be delivered encoded therein; and

delivering said stimulation signals via at least one electrode member to the implantee;

wherein the stimuli includes plasticity informative stimuli having a magnitude below a perception threshold of the implantee, the plasticity informative stimuli facilitating the production and/or release of naturally occurring neurotrophic agents into the auditory system, wherein said naturally occurring agents comprise neurotrophic factors that increase the survival of spiral ganglion cells.

99. A method of delivering stimuli to the auditory system of claim 98 wherein the stimuli is configured to be delivered to the auditory system of the implantee.

100. A method of delivering stimuli to the auditory system of claim 98 wherein positioning at least one electrode member comprises positioning said at least one electrode member in a cochlea of the implantee.

101. A method of delivering stimuli to the auditory system of claim 98 wherein said at least one electrode is adapted to deliver plasticity informative stimuli and auditory informative stimuli to the cochlea of the implantee.

102. An implantable apparatus for delivering electrical stimuli to a neural network of an implantee, the apparatus comprising:

a stimulator that generates stimulation signals; and

at least one electrode member configured to receive the stimulation signals and configured to deliver the stimuli to the neural network in response to said signals;

wherein the stimuli includes plasticity informative stimuli having a magnitude below a perception threshold of the implantee, the plasticity informative stimuli facilitating the production and/or release of naturally occurring neurotrophic agents into the neural network, and

wherein said stimuli elicits outgrowth of spiral ganglion cells towards said at least one electrode member.

103. An implantable apparatus of claim 102 wherein the apparatus delivers stimuli to the auditory system of the implantee.

104. An implantable apparatus of claim 103 wherein the perception threshold is an auditory perception threshold of the implantee.

105. An implantable apparatus of claim 102 wherein the wherein the apparatus is configured to deliver the stimuli to at least one of the cochlea, inferior colliculus, the Subthalamic Nucleus (STN), the Globus Pallidus (GPi), and the Thalamus of the implantee.

106. An implantable apparatus of claim 102 wherein the hearing prosthesis is a cochlear implant.

107. An implantable apparatus of claim 102 wherein the hearing prosthesis is a hearing aid.

108. An implantable apparatus of claim 102 wherein the apparatus has at least two electrode members and the plasticity informative stimuli is configured to be delivered simultaneously or sequentially by said at least two electrode members.

109. An implantable apparatus of claim 102 wherein the apparatus has at least two electrode members and wherein at any given time only one stimulating electrode is active.

110. An implantable apparatus of claim 102 wherein said naturally occurring neurotrophic agents comprise one or more neurotrophic factors selected from the group comprising Brain Derived Neurotrophic Factor (BDNF), NGF, NT-3, NT-4/5, NT-6, LIF, GDNF, CNTF, and IGF-I.

111. An implantable apparatus of claim 102 wherein said naturally occurring neurotrophic agents comprise neurotrophic factors that increase the survival of spiral ganglion cells.

112. A method of delivering stimuli to an auditory system of an implantee, via an stimulator electrically coupled to at least one electrode member, wherein the electrode member is positioned to deliver the stimuli to the implantee, comprising the steps of:

generating stimulation signals having the stimuli to be delivered encoded therein; and

delivering said stimulation signals via at least one electrode member to the implantee;

wherein the stimuli includes plasticity informative stimuli having a magnitude below a perception threshold of the implantee, the plasticity informative stimuli facilitating the production and/or release of naturally occurring neurotrophic agents into the auditory system, wherein said stimuli elicits outgrowth of spiral ganglion cells.

113. A method of delivering stimuli to a neural network of claim 112 wherein the stimuli provided by the stimulation signals is configured to be delivered to the auditory system of the implantee.