Comparison of Auditory Brain Stem Responses to Tone Burst and Tone Burst Masked by Notched Noise Recorded in Adults with Normal Hearing / 听力学及言语疾病杂志

ABSTRACT

Objective To compare the accuracy of auditory brain stem response (ABR) thresholds to tone burst and tone burst ipsilaterally masked by notched noise in estimating puretone thresholds of adults with normal hearing.To study characteristics of ABRs evoked by tone burst and tone burst in notched noise of two different intensities.These three kinds of ABRs were named as followstb-ABR,amtb-ABR and bmtb-ABR.Methods Puretone audiometry,ABRs to tone burst and tone burst ipsilaterally masked by notched noise of different intensities were tested in 20 adults (totally 40 ears) with normal hearing.Results ①Thresholds for tb-ABR,amtb-ABR and broth-ABR of each frequency all approximated each other,and there were no statistically significant differences between them.②The mean differences between puretone thresholds and thresholds for tb-ABR,amtb -ABR and bmtb-ABR of each frequency were all less than 15 dB.Those mean differences of different ABRs of the same frequency were approximate to each other and had no statistically differences.③No matter what kind of ABR was tested,the latencies of wave V shortened with increase of frequency in each ABR at the same intensity.When the intensity and frequency of the tone burst were the same,the latency of wave V of tb-ABR was always statistically shorter than that of amtb-ABR.The latter was also always statistically shorter than that of bmtb-ABR.Conclusion Thresholds for ABRs to tone burst and tone burst ipsilaterally masked by notched noise were useful in predicting puretone thresholds.