System for enhancing auditory stimulation and the like

• US 4,357,497 A
• Filed: 05/26/1981
• Issued: 11/02/1982
• Est. Priority Date: 09/24/1979
• Status: Expired due to Fees

• Current Assignee: Erwin S. Hochmair, Ingeborg J. Hochmair
• Original Assignee: Erwin S. Hochmair, Ingeborg J. Hochmair
• Inventors: Hochmair, Erwin S., Hochmair, Ingeborg J.
• Primary Examiner(s): Robinson, Thomas A.
• Application Number:
  US06/267,405
• Time in Patent Office: 525 Days
• Field of Search: 179/107 BC, 179/107 E, 179/1 A, 179/1 D, 179/1 AA, 179/1 SA
• US Class Current: 607/5
• CPC Class Codes: A61F 11/04 Methods or devices for enabling ear patients to achieve auditory perception through physiological senses other than hearing sense, e.g. through the touch sense electronic stimulation of auditory nerves A61N1/36036
• CPC Class Codes: A61N 1/0541 Cochlear electrodes
• CPC Class Codes: A61N 1/36038 Cochlear stimulation
• CPC Class Codes: A61N 1/372 Arrangements in connection with the implantation of stimulators
• CPC Class Codes: Y10S 128/903 Radio telemetry

Abstract

A plurality of the carrier signals are modulated by signals in the audio frequency bands. The carrier signals are transmitted to a receiver having one or more independent channels for receiving and demodulating the transmitted signals. The detected signals are applied to electrodes on a prosthetic device implanted in the cochlea with the electrodes selectively positioned in the cochlea to stimulate regions having a desired frequency response.

Claims

1. A multi-frequency system for electrical stimulation of selected tissue groups comprising:

(a) transmission means for transmitting a plurality of carrier signals each of which is modulated by a signal representing a band of frequencies, said transmission means including a plurality of signal processing channels corresponding to the plurality of bands of frequencies in the audio range, each signal processing channel including a band-pass filter for selecting a band of audio frequency signals, means for compressing the dynamic ranges of said audio frequency signals, means for compensating the loudness of said audio frequency signals dependent upon their frequency; and

a transmitter for modulating a carrier signal with the processed audio frequency signal;

(b) multi-channel receiver means for receiving said transmitted signals with each receiving channel responsive to one of said transmitted signals;

(c) electrode means for electrically contacting said selected tissue groups; and

(d) means connecting a signal from each of said receiving channels to said electrode means whereby said electrode means provides electrical stimulation.

2. A multi-frequency system as in claim 1 wherein said multi-channel receiver means includes four channels, each channel including a receiving coil, said transmitter means including two transmitting coils with each of said transmitting coils transmitting two modulated carrier signals, a first two of said receiving coils being inductively coupled to one of said transmitting coils, the other two of said receiving coils being inductively coupled to the other of said transmitting coils.

3. A multi-frequency system as in claim 1 wherein said multi-channel receiver means includes four channels, each channel including four receiving coils, said transmitting means including four transmitting coils with each of said transmitting coils transmitting a modulated carrier signal to a corresponding receiving coil, and with each of said transmitting coils being inductively coupled to a corresponding receiving coil.

4. A multi-frequency system as in claim 1 wherein said means for compression of dynamic range comprises a non-linear element.

5. A multi-frequency system as in claim 4 wherein said non-linear element is a function circuit implementing a power law associated with each of said plurality of channels.

6. A multi-frequency system as in claim 4 wherein said non-linear element is a logarithmic amplifier associated with each of said plurality of channels.

7. The multi-frequency system as in claim 1 wherein said means for compression of dynamic range comprises a gain controlled amplifier disposed in said signal processing channels.

8. For use in a system for transcutaneous electrical stimulation of a selected tissue group, a signal processing device comprising:

p1 (a) at least one signal processing channel including;

1. band-pass filtering means for passing a discrete band of frequencies through said signal processing channel,

2. means for modifying the amplitude of the filtered signals as a function of the frequency band, and

3. means for compressing the dynamic range of the filtered signals to a predetermined range;

(b) means for coupling the signals to said selected tissue group.

9. The signal processing device as in claim 8 wherein said means for coupling said signals to said selected tissue group comprises a percutaneous lead having a plurality of wires joining said signal processing channel(s) to said selected tissue group.

10. The signal processing device as in claim 8 wherein said means for coupling comprises radio frequency transmitter means coupled to said signal processing channel whereby an R.F. carrier wave is modulated by the signals emanating from said signal processing channel.

11. The signal processing device as in claim 8 and further including an input device for providing a time-varying electrical signal to said signal processing channel and a gain controlled amplifier connected between said input device and said signal processing channel.

12. The signal processing device as in claim 8 wherein said means for modifying the amplitude of said filtered signals comprises an operational transconductance amplifier means coupled to receive the output from said band-pass filtering means for producing an output current proportional to the voltage signal from said band-pass filtering means;

and means for adjusting the gain of said operational transconductance amplifier whereby the sensitivity of said signal processing channel can be established.

13. A multi-frequency system for electrical stimulation of selected tissue group comprising:

(a) at least one signal processing channel including;

1. band-pass filtering means for passing a discrete band of frequencies through said signal processing channel,

2. means for modifying the amplitude of the filtered signals as a function of the frequency band, and p2 3. means for compressing the dynamic range of the filtered signals to a predetermined range;

(b) radio-frequency transmitter means coupled to said signal processing channel for modulating an RF carrier wave by the signals emanating from said signal processing channel;

(c) a radio-frequency signal receiver adapted to be implanted subcutaneously, said receiver being coupled to the output of said radio-frequency transmitter means;

(d) electrode means for establishing electrical contact with said selected tissue group; and

(e) means connecting said receiver to said electrode means.

14. A multi-frequency system as in claim 13 wherein said transmitter means and said receiver include a plurality of transmitting and receiving channels, respectively.

15. The multi-frequency system as in claim 13, wherein said transmitter means includes an antenna coil for radiating the modulated RF carrier wave.

16. The multi-frequency system as in claim 15, and further including an ear-hook member, adapted to be removably secured to a wearer'"'"'s auricle and means physically attaching said radio frequency transmitter means and said antenna coil to said ear hook member.

17. The multi-frequency system as in claim 15, wherein said radio-frequency signal receiver is implanted subcutaneously behind the patient'"'"'s auricle and includes a receiving coil in general alignment with said antenna coil when said ear-hook is secured to said wearer'"'"'s auricle.