Frequency resolution for broadband‐noise masked normal listeners

Abstract

When evaluating frequency resolution of hearing‐impaired listeners, it is often difficult to determine if changes observed in auditory analysis with increasing auditory threshold reflect abnormal cochlear function or represent normal auditory processing at high stimulus levels. This experiment was designed to investigate the dependence of frequency‐resolution measures on threshold and signal level. Auditory‐filter characteristics, critical ratios, psychophysical tuning curves, and masking patterns were obtained from normal‐hearing listeners in quiet and in the presence of broadband noise at five levels (30 to 70 dB SPL). These findings were then compared to previously obtained frequency‐resolution results for subjects with sensorineural hearing loss whose auditory thresholds in quiet were comparable to the normal‐hearing listener's masked thresholds. These comparisons, while limited to individuals with moderate hearing loss and broadband‐noise masked normal listeners, suggest that frequency resolution observed in hearing‐impaired listeners is similar to that seen in the normal auditory system at high stimulus sound‐pressure levels. [Work supported by NIH NS 18015.]