Table 5.
Summary of studies of temporal modulation transfer functions (TMTFs) and modulation-detection interference (MDI) in listeners with sensorineural hearing loss. The major studies reviewed in this paper are listed in the first column in the order in which they are discussed in Sections II-E-1 and II-E-2. The second column describes the test stimuli. The third column (Thresh. Match?) provides information concerning the use of threshold matching to simulate hearing loss (with the noise-masking threshold-elevation procedure abbreviated as NM). The fourth column gives the number (No.) of subjects (Ss) and either the range or the mean (X̄) of ages in years of the NH and HI groups. The fifth column provides information about the stimulus levels that were used to make comparisons among the groups (e.g., equal SPL or equal SL). The final column summarizes key comparisons of NH and HI performance.
| Study | Stimulus | Thresh. Match? | No. and Ages (Years) of Ss | Level Comparisons | Summary of Findings |
|---|---|---|---|---|---|
| Bacon and Viemeister (1985) | Broadband noise carrier | No | 4 NH: X̄ = 24 6 HI: 19-68 |
Equal SPL | Shape of TMTF similar for NH and HI listeners. Modulation thresholds of HI listeners at noise spectrum levels of 30 or 40 dB SPL/Hz were in the range of 0 to 7 dB worse than those of the NH listeners who were tested at a noise spectrum level of 30 dB SPL/Hz |
| Moore et al. (1992) | Octave band of noise centered at 2 kHz | No | 3 NH: 59-76 3 HI: 59-76 |
Equal SPL or equal SL | TMTFs of impaired ear of listeners with unilateral hearing loss similar to that of the normal ear for equal SPL and SL comparisons; TMTFs in better ear of bilateral loss subjects also similar to normal data |
| Bacon and Gleitman (1992) | Broadband noise carrier | No | 5 NH: 22-29 8 HI: 11-63 |
Equal SPL or equal SL | TMTFs of HI and NH listeners were generally equivalent for both equal SPL and equal SL comparisons |
| Formby (1987) | Broadband noise carrier | No | 6 NH: 27-56 6 HI: 27-56 |
Equal Loudness | TMTFs of impaired ear of listeners with unilateral hearing loss were similar to those of normal ear for modulation rates below 200 Hz but modulation thresholds were worse than normal for modulation rates above 200 Hz |
| Lamore et al. (1984) | Broadband noise carrier | No | 10 NH: ? 32 HI: 12-20 |
Equal SL | Substantial overlap between modulation detection thresholds of NH and NH listeners; greater inter-subject variability in HI results |
| Moore and Glasberg (2001) | Sinusoidal carriers | No | 4 NH: 23-54 3 HI: 70-84 |
Equal SPL or equal SL | Modulation detection thresholds of HI listeners similar to NH data for roughly equal SL |
| Grant et al. (1998) | Broadband noise carrier | No | 4 NH: 38-52 8 HI: 58-76 |
Equal SPL | Modulation detection thresholds of HI listeners worse than NH results at the higher rates of modulation. Modulation discrimination thresholds of HI worse than NH by a factor of 3. No correlation between detection and discrimination performance for HI or NH listeners. |
| Grose and Hall (1994) | Target: 1 kHz carrier; Interference: 4 kHz carrier | No | 12 NH: 18-45 11 HI: 24-53 |
Equal SPL | Results similar for NH and HI listeners. Modulation detection thresholds at 1 kHz were unaffected by the presence of an unmodulated 4Khz tone but increased by roughly 12 dB when the 4kHz tone was 100%-modulated at rates of 10 and 25 Hz. |
| Grose and Hall (1996a) | Same as above | No | 10 NH: 20-39 10 HI: 39-57 |
Equal SPL | Results as described above for Grose and Hall (1994) |