Cochlear hearing loss independently degrades binaural processing of temporal fine structure

Evidence

The study of King et al. ( 2014 ), described above, is relevant here. Recall that they tested 46 subjects with a wide range of ages (18–83 years) and degrees of hearing loss. Thresholds for detecting IPDs in TFSp were positively correlated with absolute thresholds for both carrier frequencies (r = 0.45 for f c = 250 Hz; r = 0.40, for f c = 500 Hz). The correlations remained positive and significant when the effect of age was partialled out. Thus, hearing loss adversely affects the binaural processing of TFS. — Dijk, Pim van, Physiology, Psychoacoustics and…, 817

Several studies have shown that cochlear hearing loss is associated with a greatly reduced ability to perform the TFS1 test or similar tests (Hopkins and Moore 2007 , 2010a , 2011 ). Many hearing-impaired subjects cannot perform the task at all. Although the effects of hearing loss and age were confounded in some of these studies, the performance of older hearing-impaired subjects seems to be much worse than that of older normal-hearing subjects, suggesting that hearing loss per se adversely affects monaural TFS processing. — Dijk, Pim van, Physiology, Psychoacoustics and…, 814

Many studies have shown that cochlear hearing loss is associated with larger than normal DLFs. For a review, see Moore ( 2014 ). However, in most studies the hearing-impaired subjects were older than the normal-hearing subjects, so some (but probably not all) of the effects of hearing loss may have been due to age. DLFs for hearing-impaired subjects are not correlated with measures of frequency selectivity (Tyler et al. 1983 ; Moore and Peters 1992 ), confirming that DLFs depend on TFS information and not excitation-pattern information. Several studies have shown that cochlear hearing loss is associated with a greatly reduced ability to perform the TFS1 test or similar tests (Hopkins and Moore 2007 , 2010a , 2011 ). … Although the effects of hearing loss and age were confounded in some of these studies, the performance of older hearing-impaired subjects seems to be much worse than that of older normal-hearing subjects, suggesting that hearing loss per se adversely affects monaural TFS processing. — Dijk, Pim van, Physiology, Psychoacoustics and…, 811

Categorization

• QUESTION: How does TFS1 testing distinguish TFS from envelope cues operationally? Would be worth clarifying for the reader’s understanding of the method.
• XREF: Connects to broader theme from Zero Decibels/One Square Inch that age and environment confound perceptual measurements.
• corroborated: 4 independent passages support this claim — Dijk, Pim van, Physiology, Psychoacoustics and…, 817; Dijk, Pim van, Physiology, Psychoacoustics and…, 814; Dijk, Pim van, Physiology, Psychoacoustics and…, 811