Gap detection as a function of stimulus loudness for listeners with and without hearing loss

Temporal resolution, or the ability to process rapidly changing stimuli, has been purported to be reduced in some listeners with hearing loss while being described as normal in others. Ensuring stimulus audibility by increasing stimulus levels results in near-normal temporal resolution abilities for many listeners with hearing loss, but may also result in uncomfortably loud stimulus levels. The current study was conducted to describe temporal resolution abilities of listeners with and without hearing loss as a function of stimulus loudness. The gap detection abilities of 8 listeners with normal hearing were compared with those of 8 listeners with mild to moderate hearing losses over a wide range of intensities using a 650-Hz wide high-frequency noise marker. At low intensities, listeners with hearing loss show poor gap detection ability. As intensity increases, most listeners' performance improves and stabilizes near normal at high loudness and sensation levels. At comfortable loudness, gap detection abilities of listeners with hearing loss are less than at loud levels and are considerably poorer than normal.