40. 2021.03.13
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Sensitivity to AM
Time(s)
Amplitude
Discriminate?
Depth
Detection
threshold
(Imaginary data)
Depth
Correct
(%)
50
100
70.7
AM rate (Hz)
Depth
at
threshold
(dB)
(Viemeister 1979 J Acoust Soc Am)
Threshold depends on AM rate
Single
person
Modulation transfer
function (MTF)
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p. 41
Threshold also depends on carriers
Depth
at
threshold
(dB)
Broadband
(Dau 1997 J Acoust Soc Am)
314 Hz
31 Hz
3 Hz
(Viemeister 1979 J Acoust Soc Am)
(Lorenzi 2001 J Acoust Soc Am)
Broadband
Fixed
Fixed
Fixed
Fixed
Random
MTF
Carrier bandwidth
AM rate (Hz)
AM starting phase
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p. 42
1. A model for natural sound recognition
2. Compare AM sensitivity with human
Compare
sensitivity
Stimulus
AM
detection
Stimulus
AM
detection
Method: computational simulation Recognize
Natural
sound
Recognize
Modeling
Natural
sound
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Results: Human-like MTFs in the higher layer
1st 3rd 5th 7th 9th 11th 13th
Layers
Depth
at
threshold
(dB)
Broadband
314 Hz
31 Hz
3 Hz
Broadband
Fixed
Fixed
Fixed
Fixed
Random
Carrier
bandwidth
(Viemeister 1979 JASA)
(Dau 1997 JASA) (Lorenzi 2001 JASA)
NN
Human
AM starting
phase
AM rate (Hz)
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p. 66
MTFの分析
最適変調周波数
argmaxf(MTF(f))
カットオフ周波数
神経生理の論文によって定義が異なる
最大値の50% (Eggermont, 1998; Zhang and Kelly, 2006)
最大値の80% (Rhode and Greenberg, 1994; Kuwada and Batra, 1999)
最大値の70% = −3 dB (Joris and Yin, 1992, 1998; Joris and Smith, 1998)
最大値と最小値を9:1に分ける点 (Krishna and Semple, 2000)
絶対値0.1 (Rhode and Greenberg, 1994; Zhao and Liang, 1995)
統計的に有意となる最大の変調周波数 (Batra et al., 1989; Kuwada and Batra, 1999; Krishna and
Semple, 2000; Lu and Wang, 2000; Lu et al., 2001; Liang et al., 2002; Batra, 2006; Bartlett and Wang, 2007; Scott et
al., 2011)