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85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04
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Adult
Children
Centers
Chronological changes of CI cases and CI Chronological changes of CI cases and CI centers in Japan centers in Japan (120 million population)(120 million population)
Bilateral Cochlear Implantation on the Bilateral Cochlear Implantation on the same daysame day
1) Sound direction 1) Sound direction identificationidentification
2) Speech perception in 2) Speech perception in quietquiet
3) Speech perception in 3) Speech perception in noise noise
a) Noise from fronta) Noise from front b) Noise from right and b) Noise from right and
leftleft
Binaural hearing with CI/HA or CI/CIBinaural hearing with CI/HA or CI/CI
Mechanism of sound source detection Mechanism of sound source detection Inter-aural time difference (IInter-aural time difference (I
TD)TD) Inter-aural level difference Inter-aural level difference
(ILD)(ILD)Normally hearing subjects Normally hearing subjects
ITD; 10 ITD; 10 μμsecsec ILD; 0.5 -1 dBILD; 0.5 -1 dB
can detect the difference in 2ºcan detect the difference in 2º
Sound direction identification with bilateral earsSound direction identification with bilateral ears
Bilateral cochlear implant subjectsBilateral cochlear implant subjects ITD; 400 ITD; 400 μμsec-1msecsec-1msec ILD; 1 dBILD; 1 dB
can detect the difference in 10-25º.can detect the difference in 10-25º.
Sound direction identification in Sound direction identification in bimodal (CI/HA) hearing modebimodal (CI/HA) hearing mode
③③
1.3m1.3m 1.3m1.3m①①
②② ④④
⑤⑤
AudiometerAudiometer
SCB-40SCB-40
MethodsMethods
Stimulation:Stimulation:5 speakers at 45º 5 speakers at 45º
separationseparationwhite noise with white noise with
65dB SPL for 1 sec 65dB SPL for 1 sec 20 times from each 20 times from each
speakers at speakers at random sequencerandom sequence
Stimulation:Stimulation:5 speakers at 45º 5 speakers at 45º
separationseparationwhite noise with white noise with
65dB SPL for 1 sec 65dB SPL for 1 sec 20 times from each 20 times from each
speakers at speakers at random sequencerandom sequence
Judgment: Judgment: correct correct
22 near-missnear-miss
11 errorerror
00
Judgment: Judgment: correct correct
22 near-missnear-miss
11 errorerror
00
Subjects:Subjects: Two HA users Two HA users
whose hearing whose hearing levels were levels were symmetric.symmetric.
TT..SS.. MM..KK..
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0dB0dB
50dB50dB
100dB100dB
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Result of bilateral HA usersResult of bilateral HA users
Only 5 errors to the Only 5 errors to the adjacent speakers adjacent speakers out of 100 trialsout of 100 trials
Speakers: Speakers: trials trials (scores)(scores)L L (( - 90°- 90° ))
F F (( 0°0° ))
R R (( 90°90° ))RA RA (( 45°45° ))
LA LA (( - 45°- 45° ))19/2019/20 (( 39/4039/40 ))19/2019/20 (( 39/4039/40 ))20/2020/20 (( 40/4040/40 ))18/2018/20 (( 38/4038/40 ))19/2019/20 (( 39/4039/40 ))
95/10095/100 (( 195/200195/200 ))
Threshold Time for useCase Age Gender
CauseDeafness
Durationdeafness CI HA C I H A
12
48 M Unknown 3 y 111.3 118.8 1y 4y
359 F Unknown 1 y1 y S.O. 101.3 2y10m 20y
465 F Unknown 4 y 106.3 92.5 1y6m 8y
571 M Unknown 1 y 101.3 96.3 3y 4y
680 F Unknown 1 y 108.8 107.5 1y10m 27 y84 M Labyrinthitis 1 y 98.8 112.5 3y4m 8y
Threshold Time for useCase Age Gender
CauseDeafness
Durationdeafness Rt Lt Rt Lt
12
62 M Unknown 5 y 111.3 118.8 6 y 3 y32 F Unknown 17y S.O. 110.3 3 y 3 y
SubjectSubjectCI/HA
CI/CI
CI/HA: CI/HA: trials (scores)trials (scores)L L (( - 90°- 90° ))
F F (( 0°0° ))
R R (( 90°90° ))RA RA (( 45°45° ))
LA LA (( - 45°- 45° ))11/2011/20 (( 28/4028/40 ))
11/2011/20 (( 30/430/400 ))10/2010/20 (( 29/4029/40 ))
6/206/20 (( 23/4023/40 )) 9/209/20 (( 26/4026/40 ))
46/10046/100 (( 135/200135/200 ))
CI alone: CI alone: trials (scores)trials (scores)L L (( - 90°- 90° ))
F F (( 0°0° ))
R R (( 90°90° ))RA RA (( 45°45° ))
LA LA (( - 45°- 45° ))7/207/20 (( 19/4019/40 ))
9/209/20 (( 29/4029/40 )) 8/208/20 (( 240/40240/40 )) 7/207/20 (( 24/4024/40 )) 5/205/20 (( 209/40209/40 ))
36/10036/100 (( 115/200115/200 ))K.K.K.K.
L-CI/R-HAL-CI/R-HA
HAHA
CI/HACI/HA
CICI
Sound direction identification in Sound direction identification in binaural (CI/HA ) subjectsbinaural (CI/HA ) subjects
HA: trials (scores)HA: trials (scores)
L L (( - 90°- 90° ))
F F (( 0°0° ))
R R (( 90°90° ))RA RA (( 45°45° ))
LA LA (( - 45°- 45° )) 4/204/20 (( 15/4015/40 )) 4/204/20 (( 16/4016/40 )) 7/207/20 (( 23/4023/40 )) 5/205/20 (( 19/4019/40 )) 4/204/20 (( 12/4012/40 ))
25/10025/100 (( 85/20085/200 ))
Comparison of sound direction identification Comparison of sound direction identification scores in CI, CI-HA, HA conditionsscores in CI, CI-HA, HA conditions
100100
00
5050
HAHACI+HACI+HACICI
P=0.001P=0.001
**P=0.0197P=0.0197
******
CI/HA groupCI/HA group
Binaural hearing with Binaural hearing with
CI and HA showed CI and HA showed
significantly better significantly better
score than monaural score than monaural
hearing (CI or HA hearing (CI or HA
alone) condition.alone) condition.
Binaural hearing with Binaural hearing with
CI and HA showed CI and HA showed
significantly better significantly better
score than monaural score than monaural
hearing (CI or HA hearing (CI or HA
alone) condition.alone) condition.
Comparison of sound direction identification Comparison of sound direction identification scores in CI alone and bilateral CI conditionsscores in CI alone and bilateral CI conditions
100100
00
5050
Lt CILt CI Bil CIBil CI Rt CIRt CI
**n.s.n.s.
CI/CI groupCI/CI group
Bilateral CI subjects Bilateral CI subjects
showed better score showed better score
than monaural listening than monaural listening
with poorer CI, but with poorer CI, but
showed similar showed similar
performance when performance when
listening with the better listening with the better
CI.CI.
Bilateral CI subjects Bilateral CI subjects
showed better score showed better score
than monaural listening than monaural listening
with poorer CI, but with poorer CI, but
showed similar showed similar
performance when performance when
listening with the better listening with the better
CI.CI.
Summary for sound direction Summary for sound direction identification studyidentification study
Binaural hearing with CI/HA had advantages Binaural hearing with CI/HA had advantages
for sound direction identification.for sound direction identification.
Benefits: Aware for the direction
of alarm sign. Can identify the speakerCan identify the speaker
while talking with many while talking with many
people.people.
1) Sound source detection 1) Sound source detection
2) Better speech perception 2) Better speech perception
especially in noisy especially in noisy
circumstancescircumstances
1) Sound source detection 1) Sound source detection
2) Better speech perception 2) Better speech perception
especially in noisy especially in noisy
circumstancescircumstances
Advantages of binaural hearingAdvantages of binaural hearing
Mechanisms of better hearing with two earsMechanisms of better hearing with two ears Summation effectSummation effect Binaural unmasking effect Binaural unmasking effect
(binaural squelch effect)(binaural squelch effect) Head shadow effect (advantage)Head shadow effect (advantage)
Mechanisms of better hearing with two earsMechanisms of better hearing with two ears Summation effectSummation effect Binaural unmasking effect Binaural unmasking effect
(binaural squelch effect)(binaural squelch effect) Head shadow effect (advantage)Head shadow effect (advantage)
CICI
NNSS
CICIHAHA
2) Speech perception in quiet2) Speech perception in quiet
- summation effect – - summation effect – Speech perception score (%)Speech perception score (%) Speech reception threshold Speech reception threshold
(SRT in dB)(SRT in dB)
Binaural hearing with CI/HA or CI/CIBinaural hearing with CI/HA or CI/CI
Binmodal (CI/HA) hearing uBinmodal (CI/HA) hearing under quiet conditionnder quiet condition
****
**
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10
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60
70
80
90
100 ****
***
**
*
40 50 60 70 80 85 9055 65 7535 45 (dB)
*
Comparison of speech perception sores Comparison of speech perception sores in three conditions (HA, CI, CI/HA)in three conditions (HA, CI, CI/HA)
***
0
10
20
30
40
50
60
70
80
90
100
**
*
40 50 60 70 80 85 9055 65 7535 45 (dB)
**
*
*
*HA
CI/HA
CI
Correct % for mono-syllabic words Correct % for mono-syllabic words in binaural and monaural conditionsin binaural and monaural conditions
CI+HA CI HA0
10
20
30
40
50
60
70
80
90
CI+HA CI HA0
10
20
30
40
50
60
70
80
90 (%)(%)
(CI/HA, CI-, HA-alone)(CI/HA, CI-, HA-alone)
(%)(%)
0
10
20
30
40
50
60
70
80
CI/CI Rt-CI Lt-CI
0
10
20
30
40
50
60
70
80
CI/CI Rt-CI Lt-CI
(CI/CI, CI alone)(CI/CI, CI alone)
Two parameters for speech perception testsTwo parameters for speech perception tests
Speech reception Speech reception threshold (dB)threshold (dB)
Speech reception Speech reception score (%)score (%)
Speech reception threshold (SRT) for HINT sentences under quiet condition
Six bimodal (CI/HA) subjects Six bimodal (CI/HA) subjects
CI+HA CI HA0
10
20
30
40
50
60
70
80
90dB(A)dB(A)
**
Two bilateral CI subjects Two bilateral CI subjects
0
10
20
30
40
50
60
Bil-CI Rt-CI Lt-CI
dB(A)dB(A)
Both speech perception score Both speech perception score
(%) and reception threshold (%) and reception threshold
(SRT) were better in listening (SRT) were better in listening
with two ears than listening with two ears than listening
with CI alone condition. with CI alone condition.
Both speech perception score Both speech perception score
(%) and reception threshold (%) and reception threshold
(SRT) were better in listening (SRT) were better in listening
with two ears than listening with two ears than listening
with CI alone condition. with CI alone condition.
Summary for speech perception in quietSummary for speech perception in quiet- Summation effect -- Summation effect -
SoundSoundfrom frontfrom front
CICIHAHA
SS
If SRT is better in 2dB, it If SRT is better in 2dB, it
corresponds to 10 15% better corresponds to 10 15% better
speech perception.speech perception.
If SRT is better in 2dB, it If SRT is better in 2dB, it
corresponds to 10 15% better corresponds to 10 15% better
speech perception.speech perception.
3) Speech perception 3) Speech perception in noisein noise
a) Noise from fronta) Noise from front- examination for - examination for bilateral unmasking bilateral unmasking (squelch) effect -(squelch) effect -
Binaural hearing with CI/HA or CI/CIBinaural hearing with CI/HA or CI/CI
Binaural hearing (CI/HA) Binaural hearing (CI/HA) under noisy circumstanceunder noisy circumstance
Sound and NoiseSound and Noisefrom frontfrom front
CICIHAHA
NNSS
Speech perception scores (%) under the noise Speech perception scores (%) under the noise from frontfrom front
100**
CI/HANoise
0
20
40
60
80
CIQuiet
CINoise
CI/HAQuiet
%
Binaural unmasking (squelch) effectBinaural unmasking (squelch) effect
Speech Sound: Speech Sound: 65dBSPL65dBSPL
Multi-talker noise:Multi-talker noise:60dBSPL60dBSPL
Hearing in noise test (HINT) in binaural Hearing in noise test (HINT) in binaural hearing subjectshearing subjects
Sound and NoiseSound and Noisefrom frontfrom front
CICIHAHA
NNSS
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11
11
11
11 33
22 44 8866
55 77 99
1010
1111
1212
1313
1616 1818
17171515
1414 2020
191911
Intensity of Intensity of noisenoise (dB)(dB)
Speech Sound: Speech Sound: 65dB65dB
Multi-talker noise Multi-talker noise with variable with variable intensities at 2 dB intensities at 2 dB steps.steps.
Bil-CI Rt-CI Lt-CI0
2
4
6
8
10
12
14
16
18
HINT under the noise and speech from HINT under the noise and speech from the frontthe front
Binaural performance was better or as good as performance with the better ear alone under the condition with the speech and noise from front:
binaural unmasking (squelch) effect !!
S/N ratio (dB)S/N ratio (dB)
CI+HA CI0
5
10
15
20
25
P=0.04P=0.04
S/N ratio (dB)S/N ratio (dB)
**
3) Speech perception 3) Speech perception in noisein noise
b) Noise from b) Noise from different directionsdifferent directions
- examination for head - examination for head shadow effect -shadow effect -
Binaural hearing with CI/HA or CI/CIBinaural hearing with CI/HA or CI/CI
0
2
4
6
8
10
12
14
16
Rt-CI Lt-CI
S/N (dB)S/N (dB)
Noise from LtNoise from Lt
NN
CICI
CICI
SS
0
2
4
6
8
10
12
Rt-CI Lt-CI
S/N (dB)S/N (dB)
Noise from RtNoise from Rt
CICI
CICI
NNSS
“ “ Head shadow Head shadow advantage”advantage”
Monaural hearing under the noise Monaural hearing under the noise from right or leftfrom right or left
Front CI-side HA-side0
4
8
12
****
S/N (dB)S/N (dB)
Binaural hearing (CI/HA) under the noise Binaural hearing (CI/HA) under the noise from three directionsfrom three directions
For noise on the left or right side, binaural performance For noise on the left or right side, binaural performance can utilize can utilize “Head shadow advantage”.“Head shadow advantage”.
CICI
HAHA
SSNN
NN
NN
For noise on the left or right side, binaural performance For noise on the left or right side, binaural performance can utilize can utilize “Head shadow advantage”.“Head shadow advantage”.
NNSS
CICI
CICI
NN
NN
Binaural hearing (CI/CI) under the noise Binaural hearing (CI/CI) under the noise from three directionsfrom three directions
0
2
4
6
8
10
N-Front N-better N-poorer
S/N (dB)S/N (dB)
Conclusion -2-Conclusion -2-For the binaural hearing under the For the binaural hearing under the
noise condition “the head shadow noise condition “the head shadow
advantage” was large, while “binaural advantage” was large, while “binaural
unmasking effect” contributed little. unmasking effect” contributed little.
Karaoke bar in OsakaKaraoke bar in Osaka
END OF END OF
PRESENTATIONPRESENTATION END OF END OF
PRESENTATIONPRESENTATION
Auditory and visual information Auditory and visual information processing in auditory cortical processing in auditory cortical
areas of cochlear implant areas of cochlear implant usersusers ..
- PET activation study -- PET activation study -