K. Yasu, T. Arai, K. Kobayashi and M. Shindo, “Weighting of acoustic cues shifts to frication duration in identification of fricatives/affricates when auditory properties are degraded due to aging,” In Proc. of the Interspeech, 3152−3156, Lyon, 2013.

1. Weighting of acoustic cues shifts to
frication duration in identification of
fricatives/affricates when auditory
properties are degraded due to
aging
Keiichi Yasu, Takayuki Arai,
Kei Kobayashi, Mitsuko Shindo
Sophia University
2013/08/29 1

2. Degradation of auditory property by
aging
• Difficulty in consonant identification by
elderly people
• Degradation of auditory property is one of the
causes
– Elevation of hearing levels
– Deficit of temporal resolution
– Loudness recruitment
• And so on.
2013/08/29 2

3. Identification of fricative and affricate
(CV)
• Extending total duration of fricatives (T)
→ Identification shifts from affricates to fricatives.
• (Howell and Rosen, 1983; Kluender and Walsh, 1992)
2013/08/29 3
T
(ms)
60 80 100 120 140 160 180 200
Gradient of amplitude of frication: ⊿ Total duration of frication: T
Young Elderly

4. Identification of fricative and affricate
(VCV)
• Extending silent interval (SI) between V1 and C
-> Identified from fricative to affricate
– (Dorman et al.,1980; Gordon-Salant et al., 2006)
2013/08/29 4
SI (ms) 0 20 40 60 80 100
# 1 2 3 4 5 6
Total duration of frication: T Silent interval: SI
Young Elderly

5. Weighting shift
• Multiple cues exists:
– Longer T tend to perceived as fricative
– Shorter SI tend to perceived as fricative
– Shorter T tend to perceived as affricate
– Shorter SI tend to perceived as fricative
• Confusing condition
– Depends on listeners perception
– Weighting of cues shifts especially for elderly
listeners (Yasu et al. 2011, 2012)
2013/08/29 5
cue-trading
(Repp et al. 1978)
typical consonant

6. Goal
• Identification tests of fricative and affricate
– Degradation of auditory property by aging
• (Yasu et al., 2011, 2012, Gordon-Salant et al., 2006)
• The weighting of acoustic cues
– Re-analysis and discussing in this study
• Weighting Shift to Total duration of frication T
– Unified in different cues in CV and VCV stimuli in
simple framework
2013/08/29 6

7. Experiments
(Yasu et al. 2011, 2012)
• Participants
– 19 young listeners and 55 elderly listeners
– Auditory property measurement for elderly listeners
• Absolute threshold (f), temporal resolution (t), loudness
recruitment (r)
• Stimuli
– Continuum of CV (changing gradient of amplitude
and T)
– Continuum of VCV (changing SI and T)
• Procedure
– 2AFC
2013/08/29 7

8. Result of CV: Gradient and T
2013/08/29 8
Responserateof[∫]
1.0
0.5
0
Gradient of frication
1.0
0.5
0 20
80
140
200
T (ms)
Phonetic boundary

9. Phonetic boundary (p=0.5) in CV
2013/08/29 9
Gradientoffrication
T (ms)
1.0
0.5
0
0 100 200
Eftr

10. Weighting shift from gradient
to frication duration T
• Elderly listeners with a degradation in auditory
properties are less influenced by the gradient
of the amplitude of frication
• Aging and degradation of auditory properties
affect cue trading
2013/08/29 10
Group Y E Eftr
θ [deg] 85.2 90.8 89.5
Angle θ [deg] at phonetic boundary

11. Result of VCV: SI and T
2013/08/29 11
Responserateof[∫]
1.0
0.5
0
T (ms)SI (ms)
0
short
middle
long
30
60
90
Phonetic boundary

12. Phonetic boundary (p=0.5) in VCV
2013/08/29 12T (ms)
SI(ms)
0
short middle long
50
100

13. Weighting shift from SI
to frication duration T
• Elderly people with auditory degradations
tend to clue into frication duration T,
increasingly as the auditory degradations
complete, rather than SI
2013/08/29 13
Group Y E Eftr
θ [deg] 30.1 25.3 80.5
Angle θ [deg] at phonetic boundary

14. General discussion and conclusion
• Weighting shifts to the total duration of
frication (T) by aging
– CV: gradient of frication(⊿) to total duration (T)
– VCV: silent interval (SI) to total duration (T)
• Possible to unify into single framework
-> Total duration of frication
– for identification of fricative and affricate
2013/08/29 14
Acknowledgment:
Sophia University Open Research Center from MEXT, Japan