DETERMINING STIMULATION SIGNALS FOR NEURAL STIMULATION

• US 20090177247A1
• Filed: 10/29/2008
• Published: 07/09/2009
• Est. Priority Date: 08/21/2000
• Status: Active Grant

• Current Assignee: Cochlear Limited
• Original Assignee: Cochlear Limited
• Inventors: Neal, Tim, Dijk, Bastiaan van
• Granted Patent: US 9,008,786 B2
• Time in Patent Office: Days
• US Class Current: 607/57
• CPC Class Codes: A61N 1/36038 Cochlear stimulation
• CPC Class Codes: A61N 1/36146 specified by the stimulation parameters

Abstract

A tissue-stimulating prosthesis receives an input signal and determines a set of stimulation signals for use in generating electrical stimulation that will cause the recipient to perceive the input signal. The prosthesis determines a set of stimulation signals based on the perceptual power of at least one of the frequency components of the input signal or the perceptual power of one or more stimulation signals within the set.

Claims

1. A method of providing neural stimulation to a recipient with a tissue-stimulating prosthesis, comprising:

receiving an input signal;

determining a set of stimulation signals corresponding to said input signal in which the amplitude of at least one stimulation signal is adjusted based on the perceptual power of at least one other signal within said set; and

delivering said determined set of stimulation signals to the recipient such that the recipient perceives said input signal.

2. The method of claim 1, wherein said determining said set of stimulation signals comprises:

determining a first stimulation signal based on the perceptual power of said first stimulation signal; and

determining one or more stimulation signals which are likely to be masked by said first stimulation signal, wherein said amplitudes of said one or more stimulation signals are scaled by a scaling factor to adjust for said masking by said first stimulation signal.

3. The method of claim 2, wherein said one or more stimulation signals are scaled by multiplying said amplitude of said one or more stimulation signals by said scaling factor.

4. The method of claim 3, wherein said scaling factor is greater than 1.

5. The method of claim 3, wherein said scaling factor less than or equal to 1.

6. The method of claim 2, wherein said one or more stimulation signals comprise a plurality of stimulation signals, and wherein at least one of said plurality of stimulation signals is scaled by a different scaling factor than another one of said plurality of stimulation signals.

7. The method of claim 2, wherein said amplitudes of said one or more stimulation signals are scaled by adding a scaling factor to said amplitudes.

8. The method of claim 2, wherein said amplitudes of said one or more second stimulation signals are scaled by subtracting a scaling factor from said amplitudes.

9. The method of claim 2, wherein said amplitudes of said one or more stimulation signals are scaled by application of a function thereto selected from the group comprising:

a logarithmic function, a trigonometric function or a polynomial function

10. The method of claim 2, wherein said one or more stimulation signals comprise a plurality of stimulation signals.

11. The method of claim 10, wherein said first stimulation signal is delivered via a channel of the prosthesis terminating in an electrode, and wherein said plurality of signals likely to be masked are delivered via channels of the prosthesis having electrodes positioned symmetrically about the selected channel.

12. The method of claim 10, wherein said first stimulation signal is delivered via a channel of the prosthesis terminating in an electrode, and wherein said plurality of signals likely to be masked are delivered via channels of the prosthesis having electrodes positioned asymmetrically about the selected channel.

13. The method of claim 1, wherein said tissue-stimulating prosthesis comprises a plurality of channels each terminating in at least one electrode, and wherein determining said set of stimulation signals comprises:

selecting a first stimulation signal from a generated set of stimulation signals based on the perceptual power of said first stimulation signal, wherein said selected stimulation signal corresponds to a selected channel of said tissue-stimulating prosthesis; and

scaling one or more stimulation signals which correspond to channels having electrodes positioned adjacent said electrode of said selected channel.

14. The method of claim 13, further comprising:

scaling stimulation signals which correspond to channels having electrodes positioned on either side of the electrode of said selected channel.

15. The method of claim 1, wherein said determining said set of stimulation signals comprises:

determining a first set of one or more stimulation signals;

selecting a first stimulation from said first set based on the perceptual power of said first signal; and

adjusting the amplitude of one or more stimulation signals within said first set using information indicative of a masking effect caused by delivery of electrical stimulation corresponding to said first stimulation signal.

16. The method of claim 15, wherein said information indicative of said masking effect comprises:

pre-determined masking estimations.

17. The method of claim 11, wherein said masking estimations are determined during a fitting procedure.

18. The method of claim 2, wherein said scaling factor applied to said one or more stimulation signals is updated automatically based on characteristics of a received sound signal.

19. The method of claim 2, wherein said scaling factor applied to said one or more stimulation signals is adjustable by the recipient.

20. The method of claim 15, wherein said information indicative of said masking effect is derived from one or more psychophysical models.

21. The method of claim 20, wherein said one or more psychophysical models comprise a psychoacoustic model.

22. The method of claim 20, wherein said one or more psychophysical models comprises a psychoelectric model.

23. The method of claim 20, wherein said one or more psychophysical models comprise a psychoacoustic model and a psychoelectric model.

24. A method of providing neural stimulation to a recipient with a tissue-stimulating prosthesis having a plurality of channels for delivery of stimulation signals, comprising:

receiving an input signal;

generating stimulation signals corresponding to frequency components of said input signal;

using the perceptual power of frequency components of the input signal to select channels for delivery to the recipient of said generated stimulation signals; and

delivering to the recipient said generated stimulation signals via said selected channels.

25. The method of claim 24, wherein said using the perceptual power of said frequency components of said input signal to select channels of the stimulating prosthesis for delivery of stimulated signals comprises:

determining a first frequency component having the largest perceptual power, said first frequency component corresponding to a first selected channel of the tissue-stimulating prosthesis; and

deemphasizing one or more others channels of the prosthesis for delivery of stimulation signals.

26. The method of claim 25, wherein said first selected channel terminates in an electrode, and wherein said deemphasizing said plurality of channels comprises:

deemphasizing a plurality of channels terminating in electrodes adjacent said first selected channel.

27. The method of claim 26, further comprising:

deemphasizing channels terminating in electrodes positioned symmetrically about said electrode of said first selected channel.

28. The method of claim 27, wherein each of said plurality of deemphasized channels comprise channels having electrodes positioned on either side of, and immediately adjacent to said electrode of first selected channel.

29. The method of claim 26, further comprising:

deemphasizing channels terminating in electrodes positioned asymmetrically about said electrode of said first selected channel.

30. The method of claim 25, wherein designating said one or more channels comprises:

deemphasizing said one or more channels using data determined during a fitting procedure.

31. The method of claim 25, wherein deemphasizing said one or more channels comprises:

deemphasizing said one or more channels based on characteristics of a received sound signal.

32. The method of claim 25, wherein deemphasizing said one or more channels further comprises:

adjusting which channels are to be masked based on an input by the recipient.

33. A tissue-stimulating prosthesis for providing neural stimulation to a recipient, comprising:

a sound input configured to receive an input signal;

a stimulation signal determination module configured to determine a set of stimulation signals corresponding to said input signal in which the amplitude of at least one stimulation signal within said set is adjusted based on the perceptual power of at least one other signal within said set; and

a stimulator unit configured to deliver said stimulation signals to the recipient such that the recipient perceives said input signal.

34. The prosthesis of claim 33, wherein said stimulation signal determination module is further configured to determine a first stimulation signal based on the perceptual power of said first stimulation signal, and to determine one or more stimulation signals which are likely to be masked by said first stimulation signal, wherein said amplitude of said one or more stimulation signals are scaled to adjust for said masking by said first stimulation signal.

35. The prosthesis of claim 34, wherein said one or more stimulation signals are scaled by multiplying said amplitude of said one or more stimulation signals by a scaling factor.

36. The prosthesis of claim 35, wherein said scaling factor is greater than 1.

37. The prosthesis of claim 35, wherein said scaling factor is less than 1.

38. The prosthesis of claim 35, wherein said one or more stimulation signals comprise a plurality of stimulation signals, and wherein at least one of said plurality of stimulation signals is scaled by a different scaling factor than another one of said plurality of stimulation signals.

39. The prosthesis of claim 34, wherein said one or more stimulation signals are scaled by adding a scaling factor to said amplitude of said one or more stimulation signals.

40. The prosthesis of claim 34, wherein said one or more stimulation signals are scaled by subtracting a scaling factor from said amplitude of said one or more stimulation signals.

41. The prosthesis of claim 33, wherein said stimulation signal determination module is configured to determine a first set of one or more stimulation signals, and is configured to select a first stimulation from said first set based on the perceptual power of said first signal, and to adjust the amplitude of one or more stimulation signals within said first set using information indicative of a masking effect.

42. The prosthesis of claim 41, wherein said information indicative of said masking effect comprises:

pre-determined masking estimations.

43. The prosthesis of claim 42, wherein said masking estimations are determined during a fitting procedure.

44. The prosthesis of claim 41, wherein said information indicative of said masking effect is derived from one or more psychophysical models.

45. The prosthesis of claim 44, wherein said one or more psychophysical models comprise a psychoacoustic model.

46. The prosthesis of claim 44, wherein said one or more psychophysical models comprises a psychoelectric model.

47. The prosthesis of claim 44, wherein said one or more psychophysical models comprise a psychoacoustic model and a psychoelectric model.

48. The prosthesis of claim 34, wherein said amplitude of said second stimulation signal is scaled by through the application of a function selected from the group comprising:

a logarithmic function, a trigonometric function and a polynomial function

49. The prosthesis of claim 34, wherein said one or more stimulation signals comprise a plurality of stimulation signals, and wherein at least one of said plurality of stimulation signals is scaled by a different scaling factor than another one of said plurality of stimulation signals.

50. The prosthesis of claim 34, wherein said first stimulation signal is delivered via a channel of the prosthesis terminating in an electrode, and wherein said plurality of signals likely to be masked are delivered via channels of the prosthesis having electrodes positioned symmetrically about the selected channel.

51. The prosthesis of claim 34, wherein said first stimulation signal is delivered via a channel of the prosthesis terminating in an electrode, and wherein said plurality of signals likely to be masked are delivered via channels of the prosthesis having electrodes positioned asymmetrically about the selected channel.

52. The prosthesis of claim 34, wherein said scaling factor applied to said one or more stimulation signals is updated automatically based on characteristics of a received sound signal.

53. The prosthesis of claim 34, wherein said scaling factor applied to said one or more stimulation signals is adjustable by the recipient.

54. A tissue-stimulating prosthesis for providing neural stimulation to a recipient, comprising:

a sound input configured to receive an input signal;

a stimulation signal determination module configured to generate stimulation signals corresponding to frequency components of said input signal, and to use the perceptual power of frequency components of the input signal to select channels for delivery to the recipient of said generated stimulation signals; and

a stimulator unit configured to deliver to the recipient said generated stimulation signals via said selected channels.

55. The prosthesis of claim 54, wherein stimulation signal determination module is further configured to determine a first frequency component having the largest perceptual power, said first frequency component corresponding to a first selected channel of the tissue-stimulating prosthesis, and to configured to deemphasize one or more others channels of the prosthesis for delivery of stimulation signals.

56. The prosthesis of claim 55, wherein said first selected channel terminates in an electrode, and wherein said prosthesis is configured to deemphasize a plurality of channels terminating in electrodes adjacent said first selected channel.

57. The prosthesis of claim 56, further configured to deemphasize channels having electrodes positioned symmetrically about said electrode of said first selected channel.

58. The prosthesis of claim 57, further configured to deemphasize channels terminating in electrodes positioned on either side and immediately adjacent to said electrode of first selected channel.

59. The prosthesis of claim 56, further configured to deemphasize channels terminating in electrodes positioned asymmetrically about said electrode of said first selected channel.

60. The prosthesis of claim 55, further configured to deemphasize said channels based on a fitting procedure.

61. The prosthesis of claim 55, further configured to deemphasize said channels based on characteristics of a received sound signal.

62. The prosthesis of claim 55, further configured to receive an input from the recipient, and wherein the prosthesis is configured to deemphasize said channels based on the input.