Test On Auditory Steady-state Responses Of Normal-hearing Adults

Objective: To discuss the method of forecasting the normal-hearing adult's audio state through the thresholds of auditory steady-state response(ASSR) and the creditability of shorten the testing time of ASSR.Methods: The pure tone audiometry and ASSR to multiple simultaneous stimuli were tested in a sample of 28 normal-hearing adults(56 ears). The thresholds of pure tone and ASSR, and the searching time when ASSR thresholds appear in 500Hz,1000Hz,2000Hz,4000Hz were recored. Speculating the pure tone average(PTA) based the mean of ASSR thresholds. Analyzing the relationship between ASSR thresholds and pure tone thresholds and find weather the max researching time may influence the ASSR thresholds.Results: The ASSR thresholds at 500,1000,2000,4000 Hz were 29±8 dBHL,29±8 dBHL,28±9 dBHL and 30±10 dBHL.The test showed no significant difference between frequencies (P>0.05). ASSR thresholds were about 13dB-15dB higher than pure tone thresholds in four frequencies. There was no significant correlation between ASSR thresholds and pure tone thresholds. The predictive value of PTA was about 8 dBHL higher than substantive PTA. The max researching time in all frequencies showed no significant difference to the ASSR thresholds between 6min and 9min(χ2=0.152,1.145,0.783,3.02, P>0.05).Conclusion: The ASSR thresholds was no more than 15 dBHL higher than pure tone thresholds in normal-hearing adult. It was not suitable to predict the pure tone thresholds in normal-hearing adult through their ASSR thresholds. For ICS Chartr EP system, if we set the max research time for 6min, the ASSR thresholds'detection rate won't change and the testing time could be shorten.