STIMULUS TIMING FOR A STIMULATING MEDICAL DEVICE

• US 20100198300A1
• Filed: 02/05/2009
• Published: 08/05/2010
• Est. Priority Date: 02/05/2009
• Status: Active Grant

• Current Assignee: Cochlear Limited
• Original Assignee: Cochlear Limited
• Inventors: Smith, Zachary Mark
• Granted Patent: US 8,688,222 B2
• Time in Patent Office: Days
• US Class Current: 607/57
• CPC Class Codes: A61N 1/36038 Cochlear stimulation
• CPC Class Codes: H04R 25/505 using digital signal processing

Abstract

Methods and systems are disclosed for determining the timing of stimulation applied using a medical device. In embodiments, the medical device filters a received signal to obtain a plurality of band-pass filtered signals, each corresponding to one or more stimulation channels. The medical device then determines the envelopes of these band-pass filtered signals. Next, the medical device determines the stimulation timing (i.e., the pulse times) for the corresponding stimulation channel based on the timing of a particular phase (e.g., a peak, a minimum, etc.) of the envelope. A pulse amplitude for the stimulation channel may then be determined, and stimulation applied using the determined amplitude and pulse time.

Claims

1. A method for delivering a stimulating signal by a stimulating medical device having a plurality of electrodes, comprising:

receiving a signal;

filtering the received signal to obtain a first set of one or more band-pass filtered signals;

determining a timing envelope by determining an envelope of at least one of the band-pass filtered signals;

determining a pulse time based on when a phase of the timing envelope is equal to a specified phase;

determining an amplitude for the pulse time; and

delivering a stimulation signal using one or more of the plurality of electrodes using the determined pulse time and amplitude.

2. The method of claim 1, wherein the specified phase is equal to a phase at which the envelope is at a maximum value.

3. The method of claim 1, wherein the envelope signal has a frequency range within the perceptually-relevant range of a recipient of the stimulating signal.

4. The method of claim 1, further comprising:

filtering the signal to obtain a second set of one or more band-pass filtered signals; and

wherein determining an amplitude comprises;

determining the amplitude using at least one of the band-pass filtered signals from the second set.

5. The method of claim 4, wherein each of the band-pass filtered signals of the first set corresponds to at least one band-pass filtered signal in the second set.

6. The method of claim 5, wherein each corresponding band-pass filtered signal in the first and second sets correspond to a particular channel for delivering stimulation signals using the medical device.

7. The method of claim 6, wherein each particular channel corresponds to one or more of the electrodes for use in delivering a stimulating signal for the channel.

8. The method of claim 4, wherein determining the amplitude using at least one of the bandpass signals from the second set comprises:

determining an amplitude envelope by determining an envelope of at least one band-pass signals from the second set; and

determining the amplitude based on a value of the amplitude envelope at the determined pulse time.

9. The method of claim 1, wherein determining a timing envelope comprises:

determining a plurality of timing envelopes, each determined by determining an envelope of at least one of the band-pass filters;

wherein determining a pulse time comprises;

determining a pulse time for each of the timing envelopes; and

wherein determining an amplitude comprises;

determining an amplitude for each of the determined pulse times.

10. The method of claim 9, further comprising:

selecting a plurality of maxima from the determined pulse times and their determined amplitudes.

11. The method of claim 10, further comprising:

arbitrating between the selected maxima to determine set of stimulation pulse times and amplitudes; and

wherein delivering a stimulation signal comprises;

delivering a stimulation signal for each of the determined stimulation pulse times and amplitudes.

12. An apparatus for use in delivering a stimulating signal by a stimulating medical device having a plurality of electrodes, comprising:

a first set of one or more band-pass filters configured to filter a received signal to obtain a first set of one or more band-pass filtered signals;

a first set of at least one envelope detector configured to determine a timing envelope by determining an envelope of at least one of the band-pass filtered signals;

a first set of one or more pulse time selectors configured to determine a pulse time based on when a phase of the timing envelope is equal to a specified phase;

a first set of one or more amplitude selectors configured to determine an amplitude for the pulse time; and

a transmitter configured to transmit the determined pulse time and amplitude for use in delivering a stimulation signal using one or more of the plurality of electrodes and using the determined pulse time and amplitude.

13. The apparatus of claim 12, wherein the specified phase is equal to a phase at which the envelope is at a maximum value.

14. The apparatus of claim 12, further comprising:

a low pass filter configured to filter the timing envelope to produce a low pass filtered timing envelope signal with a frequency range within the perceptually-relevant range of a recipient of the stimulating signal.

15. The apparatus of claim 12, further comprising:

a second set of one or more band-pass filters configured to filter the signal to obtain a second set of one or more band-pass filtered signals; and

wherein amplitude selector is further configured to determine the amplitude using at least one of the band-pass filtered signals from the second set.

16. The apparatus of claim 15, wherein each of the band-pass filters of the first set corresponds to at least one band-pass filter in the second set.

17. The apparatus of claim 16, wherein each corresponding band-pass filter in the first and second sets correspond to a particular channel for delivering stimulation signals using the medical device.

18. The apparatus of claim 17, wherein each particular channel corresponds to one or more of the electrodes for use in delivering a stimulating signal for the channel.

19. The apparatus of claim 15, further comprising:

a second set of one or more envelope detectors configured to determine an amplitude envelope by determining an envelope of at least one band-pass signals from the second set; and

wherein the amplitude selector is configured to determine the amplitude based on a value of the amplitude envelope at the determined pulse time.

20. The apparatus of claim 12, wherein the first set of one or more band-pass filtered signals comprises a plurality of band-pass filtered signals;

wherein the first set of at least one envelope detector is configured to determine a timing envelope for each of the band-pass filtered signals by determining an envelope of each of the band-pass filtered signals;

wherein the first set of one or more pulse time selectors is configured to determine a pulse time for each of the timing envelopes based on when a phase of the timing envelope is equal to a specified phase; and

wherein the first set of one or more amplitude selectors is configured to determine an amplitude for each of the determined pulse times.

21. The apparatus of claim 20, further comprising:

a maxima selector configured to select a plurality of maxima from the determined pulse times and their determined amplitudes.

22. The apparatus of claim 21, further comprising:

an arbitrator configured to arbitrate between the selected maxima to determine a set of stimulation pulse times and amplitudes; and

wherein;

the transmitter is further configured to deliver a stimulation signal for each of the determined stimulation pulse times and amplitudes.

23. A computer readable medium comprising a computer program for controlling a processor to execute a method for delivering a stimulating signal by a stimulating medical device having a plurality of electrodes, the method comprising:

receiving a signal;

filtering the received signal to obtain a first set of one or more band-pass filtered signals;

determining a timing envelope by determining an envelope of at least one of the band-pass filtered signals;

determining a pulse time based on when a phase of the timing envelope is equal to a specified phase;

determining an amplitude for the pulse time; and

delivering a stimulation signal using one or more of the plurality of electrodes using the determined pulse time and amplitude.

24. A system for delivering a stimulating signal by a stimulating medical device having a plurality of electrodes, comprising

means for receiving a signal;

means for filtering the received signal to obtain a first set of one or more band-pass filtered signals;

means for determining a timing envelope by determining an envelope of at least one of the band-pass filtered signals;

means for determining a pulse time based on when a phase of the timing envelope is equal to a specified phase;

means for determining an amplitude for the pulse time; and

means for delivering a stimulation signal using one or more of the plurality of electrodes using the determined pulse time and amplitude.