AUTOMATIC MEASUREMENT OF AN EVOKED NEURAL RESPONSE CONCURRENT WITH AN INDICATION OF A PSYCHOPHYSICS REACTION

• US 20110082521A1
• Filed: 12/10/2010
• Published: 04/07/2011
• Est. Priority Date: 06/15/2004
• Status: Active Grant

• Current Assignee: Cochlear Limited
• Original Assignee: Cochlear Limited
• Inventors: Botros, Andrew, Dijk, Bastiaan van
• Granted Patent: US 8,190,268 B2
• Time in Patent Office: Days
• US Class Current: 607/57
• CPC Class Codes: A61B 5/24 Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
• CPC Class Codes: A61N 1/36039 fitting procedures

Abstract

A method of fitting to a recipient a cochlear implant including a plurality of stimulation channels. The method comprises applying to at least one stimulation channel of the cochlear implant a first stimulus signal comprising a neural response component and a psychophysics signal component, automatically measuring a strength of an evoked compound action potential (ECAP) of the recipient evoked in response to the application of the neural response component of the first stimulus signal, and simultaneously providing to a user an indication of the automatically measured strength of the ECAP and a value of the applied psychophysics signal component.

Claims

1. A method of fitting to a recipient a cochlear implant including a plurality of stimulation channels, comprising:

applying to at least one stimulation channel of the cochlear implant a first stimulus signal comprising a neural response component and a psychophysics signal component;

automatically measuring an evoked compound action potential (ECAP) of the recipient evoked in response to the application of the neural response component of the first stimulus signal; and

simultaneously providing to a user an indication of the automatically measured ECAP and a value of the applied psychophysics signal component.

2. The method of claim 1, further comprising:

comparing (i) an evoked response by the recipient to at least the psychophysics signal component to (ii) the automatically measured ECAP.

3. The method of claim 2, further comprising:

reapplying to the at least one stimulation channel of the cochlear implant a second stimulus signal comprising a neural response component and a psychophysics signal component, wherein a current of the psychophysics signal component of the second stimulus signal is higher than a current of the psychophysics signal of the first stimulus signal.

4. The method of claim 3, further comprising:

comparing (i) an evoked response by the recipient to at least the psychophysics signal component of the second stimulus signal to (ii) the automatically measured ECAP of the second stimulus signal.

5. The method of claim 4, further comprising:

establishing an initial MAP for the cochlear implant based on the comparison of the (i) evoked response by the recipient to at least the psychophysics signal component of the second stimulus signals to (ii) the automatically measured ECAP of the second stimulus signal,

wherein establishing the initial MAP for the cochlear implant includes setting at least one of a T level of the MAP or a C level of the MAP to correspond to the current of the psychophysics signal component of the second stimulus signal.

6. The method of claim 1, further comprising:

determining that the measured ECAP of the recipient evoked in response to the application of the neural response component of the first stimulus signal is indicative of no neural response by the recipient to the neural response component of the first stimulus signal;

upon the determination that the measured ECAP of the recipient evoked in response to the application of the neural response component of the first stimulus signal is indicative of no neural response by the recipient to the neural response component of the first stimulus signal, establishing an initial MAP for the cochlear implant by setting a T level of the MAP to correspond to a current that is higher than a current of the psychophysics signal component of the first stimulus signal; and

evoking a response by the recipient to the psychophysics signal component of the second stimulus signal.

7. The method of claim 1, wherein the action of applying to at least one stimulation channel of the cochlear implant a first stimulus signal comprising a neural response component and a psychophysics signal component comprises:

applying the neural response component in a burst;

applying the psychophysics signal component in a burst such that the psychophysics burst sounds, to the recipient, about the same loudness as the applied neural response component.

8. The method of claim 1, wherein the action of applying to at least one stimulation channel of the cochlear implant a first stimulus signal comprising a neural response component and a psychophysics signal component comprises:

applying the neural response component in a burst;

applying the psychophysics signal component in a burst such that the psychophysics burst sounds, to the recipient, much louder than the applied neural response component.

9. The method of claim 1, wherein the action of applying to at least one stimulation channel of the cochlear implant a first stimulus signal comprising a neural response component and a psychophysics signal component comprises:

applying the neural response component in a burst temporally adjacent to the applied psychophysics signal component.

10. The method of claim 9, wherein the action of applying to at least one stimulation channel of the cochlear implant a first stimulus signal comprising a neural response component and a psychophysics signal component comprises:

applying the neural response component in a burst and immediately thereafter applying the psychophysics signal component in a burst.

11. The method of claim 10, the burst of the neural response component comprises:

a series of pulses having a period of about one hundredth of a second.

12. The method of claim 10, the burst of the neural response component comprises:

a series of pulses having a period of about 125 milliseconds.

13. The method of claim 10, wherein the action of applying to at least one stimulation channel of the cochlear implant a first stimulus signal comprising a neural response component and a psychophysics signal component comprises:

applying the psychophysics signal component in a burst including a series of pulses having a period of about 0.2 to about 0.4 milliseconds.

14. The method of claim 10, wherein the action of applying to at least one stimulation channel of the cochlear implant a first stimulus signal comprising a neural response component and a psychophysics signal component comprises:

applying the psychophysics signal component in a burst including a series of pulses, the burst lasting about a half of a second; and

applying the neural response component in a burst including a series of pulses, wherein the psychophysics burst rate is much higher than a rate of the neural response signal.

15. An apparatus for fitting to a recipient a cochlear implant including a plurality of stimulation channels, the apparatus configured to:

apply to at least one stimulation channel of the cochlear implant a first stimulus signal comprising a neural response component and a psychophysics signal component;

automatically measure a strength of an evoked compound action potential (ECAP) of the recipient evoked in response to the application of the neural response component of the first stimulus signal; and

simultaneously automatically provide to a user of the apparatus an indication of the automatically measured strength of the ECAP and a value of the applied psychophysics signal component.

16. The apparatus of claim 15, wherein:

the apparatus includes a display;

the display of the hearing implant fitting system is configured to display a visual representation of the measured strength of the ECAP; and

the display of the hearing implant fitting system is configured to display a visual representation of the value of the applied psychophysics signal component.

17. The apparatus of claim 15, wherein the apparatus is configured to create a decision making algorithm through the use of machine learning, wherein the decision making algorithm analyzes ECAP telemetry data received from the cochlear implant to automatically measure the strength of the ECAP of the recipient evoked in response to the application of the neural response component of the first stimulus signal.

18. The apparatus of claim 15, wherein the apparatus is configured to:

apply the neural response component in a burst temporally adjacent to the applied psychophysics signal component.

19. A method of fitting to a recipient a cochlear implant including a plurality of stimulation channels, comprising:

applying a stimulus signal to a target neural region of the recipient of the cochlear implant via a stimulus signal, the stimulus signal comprising a neural response component and a psychophysics signal component,

wherein applying the stimulus signal includes applying the neural response component in a burst,

wherein applying the stimulus signal includes applying the psychophysics signal component in a burst, and

wherein the bursts are applied temporally adjacent to each other.

20. The method of claim 19, wherein the psychophysics signal component is applied immediately after the neural response component.