Frequency resolution and hearing loss

Future scientific and diagnostic interest in frequency resolution requires an evaluation of the different methods that are available to measure it. We compared three methods: (1) pure-tone thresholds in broadband noise, (2) pure-tone thresholds in the presence of a fixed pure-tone masker and (3) psychoacoustical tuning curves. We additionally obtained estimates of temporal integration and of speech intelligibility in noise. Three subject groups were tested: 10 normals, 13 subjects with a noise-induced hearing loss and 18 subjects with a cochlear hearing loss but no history of noise exposure. Generally the three measures of frequency resolution show moderate agreement with each other. Poor frequency resolution is invariably associated with a pure-tone threshold loss. Temporal integration appears unrelated either to the pure-tone threshold loss or frequency resolution. Some of the measures of frequency resolution display significant correlation with speech intelligibility in noise. However, since both variables are correlated with pure-tone threshold loss the exact relationship between frequency resolution and speech intelligibility cannot be clearly established.