Table 1.
Audiological profile of participants with auditory neuropathy.
Figure 1.
Amplitudemodulation detection thresholds as a function of modulation frequency in listeners with normal hearing (NH) and those with auditory neuropathy (AN).
The opensquarefornormal hearing, open trianglefor listeners with AN. The open trianglewith downward arrow indicates thresholds >0 dB.
Figure 2.
Frequency modulation detection threshold (FMDL) for 2 Hz and 10 Hz modulation frequencies as function of carrier frequencies (0.5, 1, 2, and 4 kHz) expressed as peak-to-peak deviation divided by center frequency in listeners with AN and normal hearing.
Figure 3.
Speech identification scores as a function of signal to noise ratio for listeners with normal hearing (open circle) and those with AN (filled square).
The error indicates 95% confidence interval.
Table 2.
Summary of Multivariate Regression Analysis.
Figure 4.
Comparison of data of four exceptional listeners with AN who had normal temporal modulation transfer function (TMTF) and poor perception of speech in noise with the remaining listeners with AN and those with normal hearing.
Panel 1: Sensitivity to modulation as a function of modulation frequency. A shaded area with single hatched line for listeners with normal hearing (NH) and double hatched line for listeners with auditory neuropathy (AN). The shaded area indicates 95% confidence interval. Individual data from each of the four listeners with AN is shown with separate symbols. Panel 2: Frequency modulation detection threshold (FMDL)for 2 Hz and 10 Hz expressed as peak-to-peak deviation divided by center frequency and plotted as a function of center frequency. The mean data of the four exceptional listeners with AN is shown separately symbol. Panel 3: Speech perception scores as a function of signal to noise ratio. The shaded area indicates 95% confidence interval. Individual data from each of the four listeners with AN is shown with separate symbols.
Figure 5.
Atypical temporal modulation transfer function (TMTF) pattern measured in listeners with AN.
Left panel shows flat pattern and right panel shows band pass pattern. In each panel, the ordinate is the amplitude modulation detection threshold, expressed in decibels as 20 log m and abscissa is modulation frequency (Hz).
Figure 6.
Frequency modulation detection threshold (FMDL) for 2 Hz and 10 Hz modulation frequencies as function of carrier frequencies (0.5, 1, 2, and 4 kHz) expressed as ΔF divided by equivalent rectangular bandwidth (ERB).
ΔF/ERB values were grossly abnormal at lower frequencies and lean towards normal function at higher frequencies.