COCHLEA ELECTRODE ARRANGEMENT, DEVICE, SYSTEM AND METHOD FOR ENHANCING MUSICAL MELODY PERCEPTION

Abstract

A cochlea electrode arrangement, system and method for enhancing musical melody perception. On each cochlear basilar membrane, according to the characteristic frequency correspondence of music notes, a phonosensitive full spectrum band corresponding to the cochlea apex to cochlea base is divided into musical response areas in response to specific musical note stimulating signals; a corresponding electrode for conducting or sensing frequency band signals is placed in each musical response area, namely, each electrode is placed in the corresponding characteristic frequency band where the music notes are located, the electrodes are divided into two groups, and a corresponding group of electrodes is implanted into cochleae on two sides respectively. Due to the fact that the electrodes are arranged in the cochleae on the two sides, the cochlea electrode arrangement is easy to implement, and the electrodes arranged in the cochleae on the two sides can perceive music better.

Claims

1. A cochlea electrode arrangement for enhancing musical melody perception, wherein nearby a cochlear basilar membrane on each side, according to the characteristic frequency correspondence of music notes, a phonosensitive full spectrum band corresponding to the cochlea apex to cochlea base is divided into frequency areas in response to specific notes; a conducting or stimulating electrode for frequency band signals is placed in each frequency area, namely each electrode is placed in the characteristic frequency band where the music notes are located, the electrodes are divided into two groups, two electrode distribution methods, namely an equalization method and a main-auxiliary method, are adopted for bilateral ears by using the characteristic of dual ears and dual tracks, a corresponding group of electrodes is implanted into cochleae on two sides respectively, and each electrode corresponds to the fundamental wave frequency point of a different note.

2. The cochlea electrode arrangement for enhancing musical melody perception as described in claim 1, wherein for the equalization method, the same number of electrodes is implanted into the bilateral cochleae respectively, and grouped into electrode arrays in an equal-pitch interval alternating manner at set frequency bands.

3. The cochlea electrode arrangement for enhancing musical melody perception as described in claim 2, wherein excessive electrodes should not be arranged in the low frequency area due to small very low note frequency intervals, meanwhile, a few very low notes are used, so representative frequency points are selected and respectively arranged at corresponding positions nearby the bilateral cochlea apexes.

4. The cochlea electrode arrangement for enhancing musical melody perception as described in claim 1, wherein 33 electrodes are respectively implanted into the remaining frequency areas in the bilateral cochleae except the low frequency areas; on one side, the arrangement of electrodes implanted into the cochlea is: the 1.sup.st electrode corresponds to the fundamental wave frequency of a B8 note; the 33.sup.rd electrode corresponds to the fundamental wave frequency of a G3 note, and the electrodes between the 1.sup.st electrode and the 33.sup.rd electrode are arranged according to a whole-tone frequency interval; the arrangement of 33 electrodes implanted into the remaining frequency areas of the cochlea on the other side except the low frequency area is: the 1.sup.st electrode corresponds to the fundamental wave frequency of a C9 note; the 33.sup.rd electrode corresponds to the fundamental wave frequency of a G#/Ab3 note, and the electrodes between the 1.sup.st electrode and the 33.sup.rd electrode are also arranged according to a whole-tone note frequency interval.

5. The cochlea electrode arrangement for enhancing musical melody perception as described in claim 4, wherein the three electrodes in the low frequency area are respectively: the 36.sup.th electrode corresponds to the fundamental wave frequency of an A1 note, the 35.sup.th electrode corresponds to the fundamental wave frequency of an E2 note, and the 34.sup.th electrode corresponds to the fundamental wave frequency of a C3 note.

6. The cochlea electrode arrangement for enhancing musical melody perception as described in claim 1, wherein as for the main-auxiliary method, different numbers of electrodes are implanted into the bilateral cochleae respectively, and grouped into electrode arrays in a specified frequency interval alternating manner at set frequency bands.

7. The cochlea electrode arrangement for enhancing musical melody perception as described in claim 6, wherein at the low frequency area, corresponding representative frequency points are selected for arranging corresponding electrodes, the electrodes are respectively implanted into the bilateral cochleae, and three electrodes are distributed on two sides respectively.

8. The cochlea electrode arrangement for enhancing musical melody perception as described in claim 1, wherein when different numbers of electrodes are implanted into the bilateral cochleae respectively, a main electrode group, totally 38 electrodes, is distributed in correspondence to the main frequency sensing area of the cochlea on one side, and an auxiliary electrode group, totally 27 electrodes, is distributed in correspondence to the main frequency sensing area of the cochlea on the other side; the arrangement of the main electrode group distributed in one cochlea is: the 1.sup.st electrode corresponds to the fundamental wave frequency of the B8 note; the 38.sup.th electrode corresponds to the fundamental wave frequency of the G3 note, and the electrodes between the 1.sup.st electrode and the 38.sup.th electrode are arranged according to the note frequency correspondence in a set manner; the arrangement of the auxiliary electrode group implanted into the other cochlea is as follows: the 1.sup.st electrode corresponds to the fundamental wave frequency of an A#/Bb8 note; the 27.sup.th electrode corresponds to the fundamental wave frequency of the G#/Ab3 note, and the electrodes between the 1.sup.st electrode and the 27.sup.th electrode are also arranged according to the note frequency correspondence in a set manner.

9. The cochlea electrode arrangement for enhancing musical melody perception as described in claim 8, wherein in the low frequency areas, the three electrodes are respectively: in the main electrode group, the 41.sup.st electrode corresponds to the fundamental wave frequency of the A1 note, the 40.sup.th electrode corresponds to the fundamental wave frequency of the E2 note, and the 39.sup.th electrode corresponds to the fundamental wave frequency of the C3 note; and in the auxiliary electrode group, the 30.sup.th electrode corresponds to the fundamental wave frequency of the A1 note, the 29.sup.th electrode corresponds to the fundamental wave frequency of the E2 note, and the 28.sup.th electrode corresponds to the fundamental wave frequency of the C3 note.

10. A cochlea electrode arrangement method for enhancing musical melody perception as described in claim 1, comprising the following steps: dividing electrodes into two groups, and implanting a corresponding group of electrodes into bilateral cochleae respectively, wherein each electrode is arranged in a corresponding characteristic frequency band where music notes are located, the electrodes are mainly concentrated in main frequency sensing areas of 100 Hz-8000 Hz, and corresponding representative frequency points are selected for arranging the electrodes in low frequency areas; wherein for an equalization method, when the electrodes are divided into two groups of the same number, the electrodes are arranged in a left-right staggered and equal interval manner in the unilateral cochlea according to fundamental wave characteristic frequencies of notes in the main frequency sensing area; and in a main-auxiliary method, when the electrodes are divided into two groups of unequal numbers, the electrodes are arranged in the unilateral cochlea according to fundamental wave characteristic frequencies of notes in a set manner.

11. A cochlea electrode array device for enhancing musical melody perception, comprising a plurality of electrodes, wherein each electrode comprises a plurality of annular electrode contacts, the annular electrode contacts are all connected with electrode circuits via metal wires with insulating layers, the electrode further comprises a flexible envelope wrapping all the electrode circuits, and the electrodes are arranged into arrays according to the electrode arrangement method of claim 10.

12. A cochlear implant system for enhancing musical melody perception, adopting the cochlea electrode array device for enhancing musical melody perception as described in claim 11, and comprising an implant part and an external part, wherein the implant part and the external part adopt a wireless communication connection mode or a wired connection mode, the implant part at least comprises an electrode array device, the external part at least comprises a sound processor and a sound acquisition device connected with the processor, sound signals are acquired by the sound acquisition device, notes and pitch intervals of a main melody of music signals are analyzed and coded by the processor, corresponding MIDI music codes are generated by the processor according to the type of a musical instrument and converted into bilateral cochlea electrode stimulating coded signals via a corresponding processing algorithm, and the stimulating coded signals are transmitted to stimulated parts via wireless communication or dedicated wired interface drive.

13. The cochlear implant system for enhancing musical melody perception as described in claim 12, wherein for the wireless communication connection mode, the electrode array device and a receiving device serve as the implant part of an cochlear implant, and a transmitter, the processor and the sound acquisition device serve as the external part of the cochlear implant.

14. The cochlear implant system for enhancing musical melody perception as described in claim 12, wherein for the wired connection mode, the electrode array device serves as the implant part of an cochlear implant, a wired interface device, a signal drive device, the processor and the sound acquisition device serve as the external part, signals acquired by the sound acquisition device are transmitted to the processor, the processor decomposes and quantifies the obtained signals to generate corresponding signals and transmits the signals to the signal drive device, the signal drive device transits each path of signals generated by drive to the wired interface device, and each path of signals is connected with each path of signals of implanted electrodes at the wired interface device to generate corresponding stimulating signals.

15. The cochlear implant system for enhancing musical melody perception as described in claim 12, wherein the wireless communication mode of the implant part and the external part may be a Bluetooth communication mode, an infrared communication mode or a radio frequency (RF) communication mode, and the wired connection mode may be a connection structure wrapped by a flexible material; and the connection structure is an optical connection structure, a thermal connection structure or a mechanical connection structure.

16. A working method of the cochlear implant system for enhancing musical melody perception based on claim 12, comprising the following steps: signals acquired by a sound acquisition device are transmitted to a processor, and the processor analyzes and encodes notes and pitch intervals of a main melody of the music signals, wherein the processor can generate corresponding MIDI music codes according to the type of a musical instrument, and processes the codes via a processing algorithm corresponding to a mode; the processor determines the location of an effective working electrode of each note according to the electrode working mode, and determines an array on each side and each electrode coding sequence; the processor converts the music codes into bilateral cochlea electrode stimulating coded signals via the processing algorithm corresponding to the mode, and the stimulating coded signals are transmitted to stimulated parts via wireless communication or dedicated wired interface drive.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] FIG. 1a shows time and frequency distribution characteristics of speech signals (na1);

[0042] FIG. 1b shows time and frequency distribution characteristics of music signals (violin C3);

[0043] FIG. 2a is a structural block diagram of a unilateral or bilateral cochlear implant system in a wireless transmission mode;

[0044] FIG. 2b is a structural block diagram of a unilateral or bilateral cochlear implant system in a wired connection mode;

[0045] FIG. 3 is a block diagram of a signal processing flow of an electrode system on each side;

[0046] FIG. 4 is a structural schematic diagram of an electrode array on each side;

[0047] FIG. 5 shows waveforms of binaural superposed musical sound simulation synthetic signals;

[0048] FIG. 6 is a waveform diagram corresponding to a section of musical melody in one embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0049] The present invention will be specified below in combination with the accompanying drawings.

[0050] Hair cells (i.e., auditory cells) on the basilar membrane of a cochlea having the function of analyzing or sensing frequency components are connected with terminal auditory nerves, and their topological locations in the cochlea correspond to the frequency components. If the perception of music is desired to be accurately reconstructed in the cerebral hearing area, so that an cochlear implant patient can feel wonderful musical melody, electrodes should be added to connect the corresponding auditory nerves. However, excessive electrodes are difficult to be implanted in the unilateral cochlea, thus, the present invention utilizes the fact that human ears have bilateral cochleae and the dual ears have a superposed sensing effect, frequency values are selected by means of an equalization method and a main-auxiliary method, and stimulating electrodes are distributed at the topological locations in the corresponding cochleae to connect the terminal auditory nerves.

[0051] Table 2.1 is a corresponding schematic table of note frequencies in an equalization method, in bilateral arrangement, the note frequencies corresponding to medium and high frequency electrodes on one side are bold, the note frequencies corresponding to medium and high frequency electrodes on the other side are italic, and the note frequencies corresponding to common electrodes arranged at the low frequency parts are bold and underlined.

[0052] In the equalization method, when bilateral electrodes are arranged specifically, the specific relations between the electrodes and the note frequencies are shown in table 3.1 and table 3.2.

[0053] Table 2.2 is a corresponding schematic table of note frequencies in a main-auxiliary method, wherein the note frequencies corresponding to medium and high frequency electrodes in the main side are bold; the note frequencies corresponding to medium and high frequency electrodes in the auxiliary side are italic; and the note frequencies corresponding to common electrodes arranged at the low frequency parts are bold and underlined.

[0054] In the main-auxiliary method, when electrodes in the main and auxiliary sides are arranged specifically, the specific relationship between the electrodes and the note frequencies are shown in table 3.3 and table 3.4.

TABLE-US-00002 TABLE 2.1 Corresponding table of note frequencies in equalization method (one side: bold; the other side: italic; low frequency common: bold + underlined) Deg. 8 Note 0 1 2 3 4 5 6 7 8 9 C 16.352 32.703 65.406 130.81 261.63 523.25 1046.5 2093.0 4186.0 8372.0 C#/Db 17.324 34.648 69.296 138.59 277.18 544.37 1108.7 2217.5 4434.9 8869.8 D 18.354 36.708 73.416 146.83 293.66 587.33 1174.7 2349.3 4698.6 9397.3 D#/Eb 19.445 38.891 77.782 155.56 311.13 622.25 1244.5 2489.0 4978.0 9956.1 E 20.60 41.20 82.407 164.8 329.6 659.2 1318.5 2637.0 5274.0 10548 F 21.827 43.654 87.307 174.61 349.23 698.46 1396.9 2793.8 5587.7 11175 F#/Eb 23.125 46.249 92.449 185.00 369.99 739.99 1480.0 2960.0 5919.9 11840 G 24.500 48.999 97.999 196.00 392.00 783.99 1568.0 3136.0 6271.9 12544 G#/Ab 25.957 51.913 103.83 207.65 415.30 830.61 1661.2 3322.4 6644.9 13290 A 27.500 55.000 110.00 220.00 440.00 880.00 1760.0 3520.0 7040.0 14080 A#/Bb 29.135 58.270 116.54 233.08 466.16 932.33 1864.7 3729.3 7458.6 14917 B 30.868 61.735 123.47 246.94 493.88 987.77 1975.5 3951.1 7902.1 15804

TABLE-US-00003 TABLE 2.2 Corresponding table of note frequencies in main-auxiliary method (main side: bold; auxiliary side: italic; low frequency common: bold + underlined) Deg. 8 Note 0 1 2 3 4 5 6 7 8 9 C 16.352 32.703 65.406 130.81 261.63 523.25 1046.5 2093.0 4186.0 8372.0 C#/Db 17.324 34.648 69.296 138.59 277.18 544.37 1108.7 2217.5 4434.9 8869.8 D 18.354 36.708 73.416 146.83 293.66 587.33 1174.7 2349.3 4698.6 9397.3 D#/Eb 19.445 38.891 77.782 155.56 311.13 622.25 1244.5 2459.0 4978.0 9956.1 E 20.60 41.20 82.407 164.8 329.6 659.2 1318.5 2637.0 5274.0 10548 F 21.827 43.654 87.307 174.61 349.23 698.46 1396.9 2793.8 5587.7 11175 F#/Eb 23.125 46.249 92.449 185.00 369.99 739.99 1480.0 2960.0 5919.9 11840 G 24.500 48.999 97.999 196.00 392.00 783.99 1568.0 3136.0 6271.9 12544 G#/Ab 25.957 51.913 103.83 207.65 415.30 830.61 1661.2 3322.4 6644.9 13290 A 27.500 55.000 110.00 220.00 440.00 880.00 1760.0 3520.0 7040.0 14080 A#/Bb 29.135 58.270 116.54 233.08 466.16 932.33 1864.7 3729.3 7458.6 14917 B 30.868 61.735 123.47 246.94 493.88 987.77 1975.5 3951.1 7902.1 15804

TABLE-US-00004 TABLE 3.1 Electrode distribution on one side in bilateral equalization method Center No. Note frequency Pass band range 36 A1 55 52.6-57.4 35 E2 82.407 80.0-84.8 34 C3 130.8 127.1-134.5 32 G#/Ab3 207.65 201.7-213.6 31 A#/Bb3 233.08 226.4-239.8 30 C4 261.63 254.1-261.1 29 D4 293.66 285.2-302.1 28 E4 329.6 320.2-339.1 27 F#/Eb4 369.99 359.4-380.6 26 G#/Ab4 415.3 403.4-427.2 25 A#/Bb4 466.16 452.8-479.5 24 C5 523.25 508.2-538.3 23 D5 587.33 570.5-604.1 22 E5 659.2 640.5-678.1 21 F#/Eb5 739.99 718.9-761.1 20 G#/Ab5 830.61 806.9-854.3 19 A#/Bb5 932.33 905.7-958.9 18 C6 1046.5 1016.7-1076.3 17 D6 1174.7 1141.1-1208.3 16 E6 1318.5 1280.7-1356.3 15 F#/Eb6 1480.00 1437.5-1522.5 14 G#/Ab6 1661.2 1613.5-1708.9 13 A#/Bb6 1864.7 1811.1-1918.3 12 C7 2093 2032.7-3045.3 11 D7 2349.3 2281.7-2416.9 10 E7 2637 2561.1-2712.9 9 F#/Eb7 2960 2874.7-3045.3 8 G#/Ab7 3322.4 3226.7-3418.1 7 A#/Bb7 3729.3 3621.9-3836.7 6 C8 4186 4065.5-4306.5 5 D8 4698.6 4563.3-4833.9 4 E8 5274 5122.1-5425.9 3 F#/Eb8 5919.9 5749.5-6090.3 2 G#/Ab8 6644.9 6454-6835.8 1 A#/Bb8 7458.6 7245.1-7672.1

TABLE-US-00005 TABLE 3.2 Electrode distribution on the other side in bilateral equalization method Center No. Note frequency Pass band range 36 A1 55 52.6-57.4 35 E2 82.407 80.0-84.8 34 C3 130.8 127.1-134.5 33 G3 196.00 190.3-201.7 32 A3 220.00 213.6-226.4 31 B3 246.94 239.8-254.1 30 C#/Db4 277.18 269.1-285.2 29 D#/Eb4 311.13 302.1-320.2 28 F4 349.23 339.1-359.4 27 G4 392.00 380.6-403.4 26 A4 440.00 427.2-452.8 25 B4 493.88 479.5-508.2 24 C#/Db5 544.37 538.3-570.5 23 D#/Eb5 622.25 604.1-640.5 22 F5 698.46 678.1-718.9 21 G5 783.99 761.1-806.9 20 A5 880.00 854.3-905.7 19 B5 987.77 958.9-1016.7 18 C#/Db6 1108.70 1076.3-1141.1 17 D#/Eb6 1244.50 1208.3-1280.7 16 F6 1396.90 1356.3-1437.5 15 G6 1568.00 1522.5-1613.5 14 A6 1760.00 1708.9-1811.1 13 B6 1975.50 1918.3-2032.7 12 C#/Db7 2217.50 2153.3-2281.7 11 D#/Eb7 2489.00 2416.9-2561.1 10 F7 2793.80 2712.9-2874.7 9 G7 3136.00 3045.3-3226.7 8 A7 3520.00 3418.1-3621.9 7 B7 3951.10 3836.7-4065.5 6 C#/Db8 4434.90 4306.5-4563.3 5 D#/Eb8 4978.00 4833.9-5122.1 4 F8 5587.70 5425.9-5749.5 3 G8 6271.90 6090.1-6453.7 2 A8 7040.00 6835.7-7244.3 1 B8 7902.10 7672.8-8131.4

TABLE-US-00006 TABLE 3.3 Electrode distribution on main side in main-auxiliary method Center No. Note frequency Pass band range 41 A1 55 52.6-57.4 40 E2 82.407 80.0-84.8 39 C3 130.8 127.1-134.5 38 G3 196.00 190.3-201.7 37 A3 220.00 213.6-226.4 36 B3 246.94 239.8-254.1 35 C4 261.63 254.1-261.1 34 D4 293.66 285.2-302.1 33 E4 329.6 320.2-339.1 32 F4 349.23 339.1-359.4 31 G4 392.00 380.6-403.4 30 A4 440.00 427.2-452.8 29 B4 493.88 479.5-508.2 28 C5 523.25 508.2-538.3 27 D5 587.33 570.5-604.1 26 E5 659.2 640.5-678.1 25 F5 698.46 678.1-718.9 24 G5 783.99 761.1-806.9 23 A5 880.00 854.3-905.7 22 B5 987.77 958.9-1016.7 21 C6 1046.5 1016.7-1076.3 20 D6 1174.7 1141.1-1208.3 19 E6 1318.5 1280.7-1356.3 18 F6 1396.90 1356.3-1437.5 17 G6 1568.00 1522.5-1613.5 16 A6 1760.00 1708.9-1811.1 15 B6 1975.50 1918.3-2032.7 14 C7 2093 2032.7-3045.3 13 D7 2349.3 2281.7-2416.9 12 E7 2637 2561.1-2712.9 11 F7 2793.80 2712.9-2874.7 10 G7 3136.00 3045.3-3226.7 9 A7 3520.00 3418.1-3621.9 8 B7 3951.10 3836.7-4065.5 7 C8 4186 4065.5-4306.5 6 D8 4698.6 4563.3-4833.9 5 E8 5274 5122.1-5425.9 4 F8 5587.70 5425.9-5749.5 3 G8 6271.90 6090.1-6453.7 2 A8 7040.00 6835.7-7244.3 1 B8 7902.10 7672.8-8131.4

TABLE-US-00007 TABLE 3.4 Electrode distribution on auxiliary side in main-auxiliary method Center No. Note frequency Pass band range 27 G#/Ab3 207.65 201.7-213.6 26 A#/Bb3 233.08 226.4-239.8 25 C#/Db4 277.18 269.1-285.2 24 D#/Eb4 311.13 302.1-320.2 23 F#/Eb4 369.99 359.4-380.6 22 G#/Ab4 415.3 403.4-427.2 21 A#/Bb4 466.16 452.8-479.5 20 C#/Db5 544.37 538.3-570.5 19 D#/Eb5 622.25 604.1-640.5 18 F#/Eb5 739.99 718.9-761.1 17 G#/Ab5 830.61 806.9-854.3 16 A#/Bb5 932.33 905.7-958.9 15 C#/Db6 1108.70 1076.3-1141.1 14 D#/Eb6 1244.50 1208.3-1280.7 13 F#/Eb6 1480.00 1437.5-1522.5 12 G#/Ab6 1661.2 1613.5-1708.9 11 A#/Bb6 1864.7 1811.1-1918.3 10 C#/Db7 2217.50 2153.3-2281.7 9 D#/Eb7 2489.00 2416.9-2561.1 8 F#/Eb7 2960 2874.7-3045.3 7 G#/Ab7 3322.4 3226.7-3418.1 6 A#/Bb7 3729.3 3621.9-3836.7 5 C#/Db8 4434.90 4306.5-4563.3 4 D#/Eb8 4978.00 4833.9-5122.1 3 F#/Eb8 5919.9 5749.5-6090.3 2 G#/Ab8 6644.9 6454-6835.8 1 A#/Bb8 7458.6 7245.1-7672.1

[0055] As shown in FIGS. 2a and 2b, when the present invention is implemented, electrodes are used in an cochlear implant system which includes an implant part and an external part, wherein the implant part includes an electrode array device arranged according to the above-mentioned mode; when the implant part is in wireless communication with the external part, the electrode array device is connected with a receiving device; and the external part includes a transmitter, a processor and a sound acquisition device connected in sequence. The sound acquisition device transmits the acquired signals to the processor, the processor transmits the signals to the transmitter after further processing, the transmitter transmits the processed signals to the receiving device wirelessly, the receiving device triggers the actions of the electrodes according to the received signals, and the corresponding electrodes act so that human ears can hear corresponding music signals.

[0056] When the implant part is in wired communication with the external part, the electrode array device serves as an implant part, and the external part includes a wired interface device, a signal drive device, a processor and a sound acquisition device connected in sequence. The sound acquisition device transmits the acquired signals to the processor, the processor transmits the signals to the signal drive device after further processing, the signal drive device transmits the processed signals to the electrode array device via the wired interface device, the electrode array device triggers the actions of the electrodes according to the received signals, and the corresponding electrodes act so that human ears can hear corresponding music signals.

[0057] The processor outside the ear can convert music signals into MIDI coded data of music by analyzing the music signals, and the data of this format can drive stimulating signals of each path of corresponding electrodes. Obviously, the electrodes distributed more closely can accurately correspond to the frequency points of music notes so that an cochlear implant patient can accurately acquire notes and harmonic information, moreover, speech characteristic frequencies can be transmitted by determining working electrodes from closer electrodes according to the principle of proximity mapping and adopting a speech processing coding strategy correspondingly, therefore, the electrode arrangement method and system consider the transmission of speech information and do not affect speech perception. However, if a few original electrodes are adopted for mapping transmission of music notes, even if the external sound processor accurately analyzes the music note information, the internal cochlea electrode cannot accurately correspond to the frequency points or connect the auditory nerves to transmit the music note information to the brain, and the music perception is still lacking. This also explains why the existing cochlear implant cannot well perceive music.

[0058] Experimental studies further discover that human ears have binaural phonosensitive superposition characteristic, and this characteristic is not only beneficial to distinguishing a sound source and improving the orientation capability of the sound source, but also can integrate sound effects of the brain stem area, i.e., can increase the volume of sound and superpose musical melody and harmonic information.

[0059] The signal processing flow of electrodes on each side in the cochlear implant system is as shown in FIG. 3:

[0060] Step 1: determining notes and pitch intervals (similar to MIDI coded information) of music;

[0061] Step 2: determining fundamental frequencies and harmonic frequencies of the notes;

[0062] Step 3: determining a music tone, and adjusting relevant coefficients;

[0063] Step 4: according to an electrode working mode including an equalization bilateral mode, a main-auxiliary bilateral mode, an equalization unilateral mode, a main-auxiliary unilateral mode, a music mode/speech mode and the like, determining the locations of effective working electrodes of the notes according to multiple principles or strategies, e.g., critical bands, no distinguishing sides of notes, same-side proximal correspondence, appropriate abandoning, etc.;

[0064] Step 5: determining working electrode locations on each side and the signal coding sequence of each electrode;

[0065] Step 6: driving or converting electrode codes, and generating stimulating pulse signals.

[0066] In this embodiment, for the multi-channel superposed sensing effect of musical melody, we made special simulation analysis, supposing that the optimal restoration effect of cochlear implant can reach normal human binaural perception, so we adopted normal human ears for simulation. As shown in FIG. 5, the upper and lower waveforms are respectively time domain waveforms of sound signals heard by left and right track cochleae, wherein the upper left track waveform shows simulated sound synthesized by left ear electrodes, including synthetic sound signals of fundamental waves and main harmonics of corresponding notes; and the lower right track waveform shows simulated sound synthesized by right ear electrodes, including synthetic sound signals of fundamental waves and main harmonics of corresponding notes. Thus, the music heard at the cerebral hearing area alternatively transmit and synthesizing by left and right tracks, and its melodic perception on segments is complete and accurate.

[0067] Experimental results show that the dual track technology can transmit more sub-band characteristics of music signals, and can transmit fundamental wave and key harmonic components more accurately and conveniently, thus increasing the electrode number of cochlear implant in other ways.

[0068] The tone of music notes is mainly determined by fundamental wave frequencies, while the timbre of tones is determined according to spectrum characteristics, i.e., determined by the ratio of fundamental waves to harmonics and the quantity of harmonics. The electrode arrangement solution of this patent just shows that the fundamental wave frequencies needed by all the music note expressions are firstly distributed well and then divided into two groups for bilateral arrangement to reduce the number of unilateral electrodes and lower the arrangement difficulty, and then the fundamental wave and harmonic frequencies of a certain note which needs to be expressed are mapped to an electrode array on one side according to a certain principle, thus ensuring that the same note works at the electrodes on one side and different notes can be expressed at the electrode arrays on different sides, and then realizing that the whole music segment adopts a melody processing strategy of bilaterally and alternatively synthesizing the sound effect. In actual corresponding conversion and expression, the center frequencies of a few harmonics may proximally fall onto the electrode locations on the other side, and this situation may be handled by adopting the principle of same-side proximity or appropriate abandoning.

[0069] In order to illustrate the effects achieved by the electrode arrangement mode of the present invention better, the present invention gives another embodiment:

[0070] Based on the above-mentioned dual track cochlea electrode arrangement method, the cochlear implant music sound processor generates corresponding electrode stimulating signals according to the electrode working mode and coding strategy and the signal processing flow of FIG. 3, wherein if the notes are lower, there are more harmonics in the music perception frequency band range and more corresponding stimulating electrodes; and if the notes are higher, there are less harmonics and less effective stimulating electrodes. When each note working electrode is determined, each effective working electrode, i.e., each electrode in the same-side cochlea where fundamental waves and effective harmonics are accurately or in approximate correspondence, is determined according to the principle of critical bands, wherein individual harmonics may be abandoned, e.g., the harmonics approximated to the electrodes on the other side. This analysis and processing operation is completed by the external sound processor.

[0071] For different musical instruments, the amplitude ratio relationships of harmonic components thereof are different, so parameters are often adjusted appropriately according to the type of a musical instrument.

[0072] The working condition of electrodes will be illustrated, taking a simple melody as an example:

[0073] A musical melody composed of three notes A3, G3 and C4 is selected, the note intervals are supposed to be equal, and the signal waveform is shown in FIG. 6.

[0074] Fundamental waves of the notes are determined at first, and then alternative electrodes of the fundamental waves and harmonics of the notes are allocated according to the processing flow of FIG. 3 and the coding strategy (i.e., critical band limitation, determining working electrodes on the basis that the harmonics of the same note are on the same side, abandoning the electrodes corresponding to the harmonics on different sides, etc.), as shown in tables 4.1, 4.2 and 4.3, to stimulate the auditory nerve system, thereby ensuring that music signals of the same note on random sides are connected to auditory nerves for stimulating, without destroying the integrity of note perception. In this case, each working electrode is determined on one side for each note, different notes may work on the same side or work alternately on different sides, and the complete musical melody is perceived by the superposition effect that the bilateral cochlea electrode arrays stimulate the auditory nerves.

[0075] If in a bilateral equalized electrode mode, for a melody section A3, G3 and C4, the 1.sup.st and 2.sup.nd notes work on the electrodes of one side, while the 3.sup.rd note works on the electrodes of the other side, e.g., table 4.1 gives an electrode condition that the 1.sup.st (A3) and 2.sup.nd (G3) notes work in sequence on one side, and table 4.2 gives a working condition of electrodes that the 3.sup.rd note C4 is on the other side.

[0076] If in a main-auxiliary bilateral electrode mode, for the melody section A3, G3 and C4, because the fundamental frequencies are distributed on the main side, the three notes work on the main side cochlea electrodes in sequence, wherein the specific working condition is shown in table 4.3.

TABLE-US-00008 TABLE 4.1 1.sup.st (A3) and 2.sup.nd (G3) notes sequentially work on electrodes in equalization binaural mode (on one side) Center No. Note frequency Pass band range 36 A1 55 52.6-57.4 35 E2 82.407 80.0-84.8 34 C3 130.8 127.1-134.5 33 G3 196.00 190.3-201.7 32 A3 220.00 213.6-226.4 31 B3 246.94 239.8-254.1 30 C#/Db4 277.18 269.1-285.2 29 D#/Eb4 311.13 302.1-320.2 28 F4 349.23 339.1-359.4 27 G4 392.00 380.6-403.4 26 A4 440.00 427.2-452.8 25 B4 493.88 479.5-508.2 24 C#/Db5 544.37 538.3-570.5 23 D#/Eb5 622.25 604.1-640.5 22 F5 698.46 678.1-718.9 21 G5 783.99 761.1-806.9 20 A5 880.00 854.3-905.7 19 B5 987.77 958.9-1016.7 18 C#/Db6 1108.70 1076.3-1141.1 17 D#/Eb6 1244.50 1208.3-1280.7 16 F6 1396.90 1356.3-1437.5 15 G6 1568.00 1522.5-1613.5 14 A6 1760.00 1708.9-1811.1 13 B6 1975.50 1918.3-2032.7 12 C#/Db7 2217.50 2153.3-2281.7 11 D#/Eb7 2489.00 2416.9-2561.1 10 F7 2793.80 2712.9-2874.7 9 G7 3136.00 3045.3-3226.7 8 A7 3520.00 3418.1-3621.9 7 B7 3951.10 3836.7-4065.5 6 C#/Db8 4434.90 4306.5-4563.3 5 D#/Eb8 4978.00 4833.9-5122.1 4 F8 5587.70 5425.9-5749.5 3 G8 6271.90 6090.1-6453.7 2 A8 7040.00 6835.7-7244.3 1 B8 7902.10 7672.8-8131.4

TABLE-US-00009 TABLE 4.3 1.sup.st (A3), 2.sup.nd (G3) and 3.sup.rd (C4) note works on electrodes in main-auxiliary bilateral mode (sequentially on main side) Center No. Note frequency Pass band range 41 A1 55 52.6-57.4 40 E2 82.407 80.0-84.8 39 C3 130.8 127.1-134.5 38 G3 196.00 190.3-201.7 37 A3 220.00 213.6-226.4 36 B3 246.94 239.8-254.1 35 C4 261.63 254.1-261.1 34 D4 293.66 285.2-302.1 33 E4 329.6 320.2-339.1 32 F4 349.23 339.1-359.4 31 G4 392.00 380.6-403.4 30 A4 440.00 427.2-452.8 29 B4 493.88 479.5-508.2 28 C5 523.25 508.2-538.3 27 D5 587.33 570.5-604.1 26 E5 659.2 640.5-678.1 25 F5 698.46 678.1-718.9 24 G5 783.99 761.1-806.9 23 A5 880.00 854.3-905.7 22 B5 987.77 958.9-1016.7 21 C6 1046.5 1016.7-1076.3 20 D6 1174.7 1141.1-1208.3 19 E6 1318.5 1280.7-1356.3 18 F6 1396.90 1356.3-1437.5 17 G6 1568.00 1522.5-1613.5 16 A6 1760.00 1708.9-1811.1 15 B6 1975.50 1918.3-2032.7 14 C7 2093 2032.7-3045.3 13 D7 2349.3 2281.7-2416.9 12 E7 2637 2561.1-2712.9 11 F7 2793.80 2712.9-2874.7 10 G7 3136.00 3045.3-3226.7 9 A7 3520.00 3418.1-3621.9 8 B7 3951.10 3836.7-4065.5 7 C8 4186 4065.5-4306.5 6 D8 4698.6 4563.3-4833.9 5 E8 5274 5122.1-5425.9 4 F8 5587.70 5425.9-5749.5 3 G8 6271.90 6090.1-6453.7 2 A8 7040.00 6835.7-7244.3 1 B8 7902.10 7672.8-8131.4

[0077] In addition, with the development of technology, when the arrangement of cochlea electrodes is not limited by the realizing process, it is the most ideal design that all the frequency points in tables 2.1 and 2.2 are arranged in the unilateral cochlea, and when all the electrodes are arranged in a unilateral ear, said cochlear implant device and corresponding optimization system are still applicable.

[0078] Although the specific embodiments of the present invention are described above in combination with the accompanying drawings, the protection scope of the present invention is not limited thereto. It should be appreciated by those skilled in the art that various modifications or variations made by those skilled in the art without any creative effort based on the technical solution of the present invention shall fall into the protection scope of the present invention.