Investigating the effect of extended high-frequency hearing loss on duration pattern sequence test

Abstract

Background and Aim: Temporal processing is affected in people exposed to occupational noi­se. The primary goal of this study was to eva­luate the temporal processing of people exposed to occupational noise of more than 85 dB A but have not experienced clinically significant chan­ges at hearing thresholds at conventional frequ­encies.
 Methods: A comparison between groups were designed using individuals exposed to occupa­tional noise (n = 15 as the case group) and non-exposed individuals (n = 16 as the control gro­up). Two groups were age-matched (p < 0.05). The extended high-frequency audiometric thre­sholds and temporal processing system were evaluated through a duration pattern sequence test. Finally, the correlation between the exten­ded high-frequency hearing thresholds and the duration pattern test scores was investigated.
 Results: The case group had significantly high­er hearing thresholds than the control group at 14, 15, and 16 kHz (p < 0.05). Although in other frequencies, the mean hearing thresholds in the case group was higher than the control group, the difference was not significant. Also, the case group had significantly lower duration pattern sequence scores than the control group in the right (p = 0.02) and the left ears (p = 0.03). There was no correlation between extended high-frequency hearing thresholds and duration pattern sequence test scores.
 Conclusion: In people exposed to occupational noise, both extended high-frequency thresholds and temporal processing in lower frequency ran­ges (with normal hearing thresholds) are inter­rupted.