Gap Detection Threshold in Ears with and without Spontaneous Otoacoustic Emissions

Gap detection was measured for two groups of normally hearing young adults using broad-band noise stimuli. Group I consisted of subjects who exhibitcd both strong spontaneous and click-evoked otoacoustic emissions (SOAEs and CEOAEs). Group II included individuals with no SOms in either ear and weak CEOAEs. An adaptive 2FC gap detection task was performed for the stimuli presented at either 10, 20, 30, or 50 dB SL. At 10 dB SL stimulus level, the ears in Group 1 exhibited greater intersubject variability and higher mean gap detection thresholds than those in Group ll. At higher SLs, there were no differences between the results for the two groups. A short gap in the broad-band stimulus presented near the threshold is masked by SOAEs and emissions evoked by the stimulus.