Pulse burst electrical stimulation of nerve or tissue fibers

• US 20050222644A1
• Filed: 03/30/2005
• Published: 10/06/2005
• Est. Priority Date: 03/31/2004
• Status: Active Grant

• Current Assignee: Cochlear Limited
• Original Assignee: Cochlear Limited
• Inventors: von Wallenberg, Ernst, Killian, Matthijs, Smoorenburg, Guido
• Granted Patent: US 7,333,858 B2
• Time in Patent Office: Days
• US Class Current: 607/57
• CPC Class Codes: A61N 1/36038 Cochlear stimulation

Abstract

A method for stimulating nerve or tissue fibers and a prosthetic hearing device implanting same. The method comprises: generating a stimulation signal comprising a plurality of pulse bursts each comprising a plurality of pulses; and distributing said plurality of pulse bursts across one or more electrodes each operatively coupled to nerve or tissue fibers such that each of said plurality of pulse bursts delivers a charge to said nerve or tissue fibers to cause dispersed firing in said nerve or tissue fibers.

Claims

1. A method of stimulating nerve or tissue fibers comprising:

generating a stimulation signal comprising a plurality of pulse bursts each comprising a plurality of pulses; and

distributing said plurality of pulse bursts across one or more electrodes each operatively coupled to nerve or tissue fibers such that each of said plurality of pulse bursts delivers a charge to said nerve or tissue fibers to cause dispersed firing in said nerve or tissue fibers.

2. The method of claim 1, wherein the nerve or tissue fibers comprise auditory nerve fibers.

3. The method of claim 1, wherein said generating a stimulation signal comprises:

generating a stimulation signal in accordance with an implemented speech processing strategy.

4. The method of claim 3, wherein said generating a stimulation signal in accordance with an implemented speech processing strategy comprises:

generating a stimulation signal in accordance with an implemented low-rate speech processing strategy.

5. The method of claim 4, wherein generating a stimulation signal comprising a plurality of pulse bursts each comprising a plurality of pulses at a pulse rate of less than approximately 500 pulses per second.

6. The method of claim 1, wherein one or more of the plurality of the pulse bursts is a ramped pulse burst.

7. The method of claim 5, wherein each of said one or more ramped pulse bursts has an approximate linear intensity function.

8. The method of claim 7, wherein said approximate linear intensity function of said one or more ramped pulse bursts is a linearly increasing intensity function.

9. The method of claim 8, wherein said approximate linearly increasing intensity function of said one or more ramped pulse bursts are progressively increasing across successively occurring ramped pulse bursts.

10. The method of claim 6, wherein said one or more ramped pulse bursts has an approximate exponential intensity function.

11. The method of claim 6, wherein said one or more ramped pulse bursts has a staggered intensity function.

12. The method of claim 1, wherein one or more of said plurality of pulses of said plurality of pulse bursts of said stimulation signal are biphasic pulses.

13. The method of claim 1, wherein one or more of said plurality of pulses of said plurality of pulse bursts of said stimulation signal are monophasic pulses.

14. The method of claim 0.1, wherein one or more of said plurality of pulses of said plurality of pulse bursts of said stimulation signal have a substantially square waveform.

15. The method of claim 1, wherein one or more of said plurality of pulses of said plurality of pulse bursts of said stimulation signal have a substantially sinusoidal waveform.

16. The method of claim 1, wherein one or more of said plurality of pulses of said plurality of pulse bursts of said stimulation signal have a substantially sawtooth waveform.

17. The method of claim 1, wherein said plurality of pulses of one or more of said plurality of pulse bursts of said stimulation signal have a different duration.

18. The method of claim 1, wherein said plurality of pulses of one or more of said plurality of pulse bursts of said stimulation signal have a different amplitude.

19. The method of claim 1, wherein said distributing said plurality of pulse bursts across one or more electrodes comprises:

distributing said plurality of pulse bursts across said one or more electrodes such that said plurality of pulses of at least one of said plurality of pulse bursts occurring on one of said one or more electrodes are interleaved with said plurality of pulses of at least one other of said plurality of pulse bursts occurring on a different one of said one or more electrodes.

20. The method of claim 19, wherein distributing said plurality of pulse bursts across said one or more electrodes comprises:

distributing said plurality of pulse bursts across said one or more electrodes such that said plurality of pulses of at least one of said plurality of pulse bursts occurring on one of said one or more electrodes are repeatedly interleaved with said plurality of pulses of at least one other of said plurality of pulse bursts occurring on a different one of said one or more electrodes.

21. The method of claim 1, wherein a first plurality of said plurality of pulses bursts is sequentially distributed on said one or more electrode.

22. The method of claim 1, wherein at least two of the pulse bursts are simultaneously distributed on two or more of said one or more electrodes.

23. The method of claim 1, wherein distributing said plurality of pulse bursts across one or more electrodes comprises:

distributing at least some of said plurality of pulse bursts across said one or more electrodes so as to enhance temporal cues when stimulating the nerve fibers.

24. The method of claim 23, wherein said one or more electrodes comprising one or more high frequency electrodes and one or more low frequency electrodes each operatively coupled to a nerve fiber which responds to high frequency stimulation signals or low frequency stimulation signals, respectively, and

wherein a first portion of said plurality of pulse bursts are distributed on said one or more low frequency electrodes and a second portion of said plurality of pulse bursts are distributed on said one or more high frequency electrodes.

25. The method of claim 24, wherein said one or more low frequency electrodes are operatively coupled to nerve fibers that respond to stimulation below 500 Hz.

26. The method of claim 24, wherein said one or more high frequency electrodes are operatively coupled to nerve fibers that respond to stimulation above 500 Hz.

27. The method of claim 24, wherein said first portion of said plurality of pulse bursts have a longer duration than said second portion of said plurality of pulses bursts.

28. The method of claim 24, wherein said first portion of said plurality of pulse bursts have a longer interval than said second portion of said plurality of pulses bursts.

29. The method of claim 24, wherein said plurality of pulses of said first portion of said plurality of pulse bursts have a longer duration than said plurality of pulses of said second portion of said plurality of pulses bursts.

30. A method of stimulating nerve fibers using electrodes operatively coupled to the nerve fibers comprising:

generating a stimulation signal comprising a first plurality of pulse bursts having a first duration and a second plurality of pulse bursts having a second duration that is less than said first duration;

distributing said first plurality of pulse bursts across one or more electrodes operatively coupled to nerve fibers responsive to low frequency stimulation; and

distributing said second plurality of pulse bursts across one or more electrodes operatively coupled to nerve fibers responsive to high frequency stimulation.

31. The method of claim 30, wherein the nerve fibers are auditory nerve fibers.

32. The method of claim 30, wherein each of said first and second plurality of pulse bursts delivers a charge to the respective nerve fibers sufficient to cause dispersed firing of the nerve fibers.

33. The method of claim 30, wherein said nerve fibers responsive to low frequency stimulation are responsive to stimulation below 500 Hz.

34. The method of claim 30, wherein nerve fibers responsive to high frequency stimulation are responsive to stimulation above 500 Hz.

35. The method of claim 30, wherein said first plurality of pulse bursts has at least two pulse bursts separated by a first interval, and wherein said second plurality of pulse bursts has at least two pulse bursts separated by a second interval that is less than said first interval.

36. The method of claim 30, wherein a speech processor implementing a low-rate speech processing strategy generates said stimulation signal.

37. The method of claim 30, wherein one or more of said plurality of pulse bursts is ramped.

38. A prosthetic hearing device, comprising:

means for generating a stimulation signal from an ambient sound;

means for defining one or more pulse bursts in said stimulation signal; and

means for distributing said pulse bursts across one or more electrodes so as to cause dispersed firing of nerve fibers.

39. The prosthetic hearing device of claim 38, further comprising:

means for defining one or more ramping pulses in said stimulation signal.

40. The prosthetic hearing device of claim 38, wherein the nerve fibers are auditory nerve fibers.

41. The prosthetic hearing device of claim 38, wherein said means for distributing said pulse bursts across one or more electrodes comprises:

means for distributing a first plurality of pulse bursts across one or more electrodes operatively coupled to nerve fibers responsive to low frequency stimulation; and

means for distributing a second plurality of pulse bursts across one or more electrodes operatively coupled to nerve fibers responsive to high frequency stimulation.

42. The prosthetic hearing device of claim 41, wherein said nerve fibers responsive to low frequency stimulation are responsive to stimulation below 500 Hz, and said nerve fibers responsive to high frequency stimulation are responsive to stimulation above 500 Hz.