A new technique for measuring spectral shape discrimination

Abstract

A new technique for measuring the ability of listeners to discriminate between sounds on the basis of spectral shape—called “auditory profile analysis”—is described. In this technique, the signal is a series of intensity increments and decrements to an equal‐level multitone reference spectrum. For any stimulus trial, the signal is either an intensity increment to the odd‐numbered tones and an intensity decrement to the even‐numbered tones, or vice‐versa. The advantage of the technique is that it reduces, by one‐half (in a two‐down, one‐up adaptive procedure), the range of the random, within‐trial rove in overall level needed to limit the usefulness of level cues. Using this technique, discrimination performance was measured for a group of normally hearing listeners for broadband, low‐pass, and high‐pass filtered conditions, and for individual hearing‐impaired listeners. The results indicated that the new technique appears to be well suited for studying auditory profile analysis in hearing‐impaired listeners where the range of sound intensities that may be presented is often quite limited. [Work supported by NIH/NIDCD.]