Across-frequency loudness matches with pure tones and narrow-band noises

Abstract

Loudness matches between stimuli that differ in frequency are difficult, presumably due to the strong pitch differences which make it challenging to focus on loudness exclusively. It is hypothesized that the use of stimuli with a less salient pitch percept (but that still permit relatively frequency-specific excitation of the cochlea) would allow for more accurate across-frequency loudness matches. This would permit more stable comparisons of loudness growth between frequency regions (corresponding to normal and elevated thresholds) as is often the need in studies involving hearing-impaired subjects. In this study, normal-hearing listeners were evaluated in loudness matching tasks with two types of stimuli: pure tones and narrow bands of noise (with corresponding center frequencies). Listeners matched the loudness of a stimulus in one frequency region with a stimulus in another frequency region. The stimuli were either two pure tones, two narrow-band noises, or a pure tone and a narrow-band noise. The results will be evaluated based on predictions from an excitation pattern model and transitivity to determine if more accurate predictions are possible using narrow-band noise stimuli. [Work supported by the University of Minnesota.]