Communication disorders in subjects with normal hearing: a behavioral and electrophysiological study

Hearing thresholds are not always predictive of performance in environments with reduced extrinsic redundancy. OBJECTIVE: To investigate the communication disorders reported by adults with normal hearing, and to assess their underlying conditions through behavioral and electrophysiological testing. METHOD: This case control study enrolled 20 adults with normal hearing thresholds and divided them into two groups: a case group with 10 adults with hearing impairment-related communication disorders and a control group with 10 adults with normal hearing. The frequency of occurrence of communication difficulties was recorded during speech recognition tests run in quiet and noisy conditions, audiometry, and auditory evoked brainstem potential testing. RESULTS: Case group subjects differed statistically from controls only in self-reported scores of hearing impairment. The groups did not differ in the other ratings. A positive correlation was found between hearing thresholds and scores on self-reported impairment. CONCLUSION: The combination of hearing complaints and unaltered audiograms was not correlated with differences in performance in speech recognition testing in noisy conditions or in the remaining evaluations. Correlation analysis showed that the higher the pure tone thresholds, the greater were the reported communication difficulties, even in thresholds between 0 and 25 dB.