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Background Some evidence suggests that young adults exhibit a selective laterality of auditory brainstem response (ABR) elicited with speech stimuli. Little is known about such an auditory laterality in older adults. Objective The aim of this study was to investigate possible asymmetric auditory brainstem processing between right and left ear presentation in older adults. Methods Sixty-two older adults presenting with normal hearing thresholds according to their age and who were native speakers of Quebec French participated in this study. ABR was recorded using click and a 40-ms /da/ syllable. ABR was elicited through monaural right and monaural left stimulation. Latency and amplitude for click-and speech-ABR components were compared between right and left ear presentations. In addition, for the /da/ syllable, a fast Fourier transform analysis of the sustained frequency-following response (FFR) of the vowel was performed along with stimulus-to-response and right-left ear correlation analyses. Results No significant differences between right and left ear presentation were found for amplitudes and latencies of the click-ABR components. Significantly shorter latencies for right ear presentation as compared to left ear presentation were observed for onset and offset transient components (V, A and O), sustained components (D and E), and voiced transition components (C) of the speech-ABR. In addition, the spectral amplitude of the fundamental frequency (F0) was significantly larger for the left ear presentation than the right ear presentation. Conclusions Results of this study show that older adults with normal hearing exhibit symmetric encoding for click stimuli at the brainstem level between the right and left ear presentation. However, they present with brainstem asymmetries for the encoding of selective stimulus components of the speech-ABR between the right and left ear presentation. The right ear presentation of a /da/ syllable elicited reduced neural timing for both transient and sustained components compared to the left ear. Conversely, a stronger left ear F0 encoding was observed. These findings suggest that at a preattentive, sensory stage of auditory processing, older adults lateralize speech stimuli similarly to young adults.

Purpose: to verify the association between self-reported dizziness, degree and symmetry of hearing loss, age and gender in a sample of older adults. Methods: this retrospective study included the analysis of 440 records of older adults with a mean age of 72.9 years, enrolled from 2011 to 2015 in an auditory rehabilitation service. Binary logistic regression models were performed between the variables, and the data was analyzed using the SPSS 24.00 software. For all tests, alpha values were considered significant when lower than 0.05. Results: in the sample, 78 (17.7%) older adults had asymmetric hearing loss, and 27 (34.6%) of them complained of dizziness. Self-reported complaint of dizziness was significantly associated with female gender (p<0,001), to severe hearing loss (p<0,001), age under 70 years, and with asymmetric hearing loss(p<0,001). Conclusion: in this study, younger female elderlies with severe asymmetric hearing loss presented self-reported complaint of dizziness . These results suggest that this population should be routinely screened for balance problems in order to provide rehabilitation programs to avoid future falls.