Comparison between the auditory lateralization ability of normal hearing elderly and youth with filtered noise

Abstract

Background and Aim: Aging affects the audi­tory lateralization function that is achieved thr­ough processing binaural cues. One of the most important benefits of this process, along with getting informed of sound location, is increasing signal to noise ratio and improvement of speech comprehension in crowded environments, which is one of the most common hearing complaints in the elderly. This study aimed to compare the performance of the lateralization function under the headphone conditions between the elderly and the youth, with a filtered noise stimulus. Methods: This study was performed between 22 elderly aged 60−80 and 22 young people aged 20−30. The auditory threshold was less than 25 dB HL in 250 to 4000 Hz frequencies in both groups. By applying a time delay of −880 to +880 microsecond and the intensity differe­nce of −10 to +10 dB between the two ears, and with high-pass and low-pass noise stimulus, the lateralization function was examined. For descr­iption of the lateralization function, scatter diag­ram and in order to compare the results, paired t-test and independent t-test were used. Results: Findings showed that the elderly's err­ors were increased in all tests compared to those of the youth group. There was a significant difference (p < 0.05) between the two groups in lateralization by time clues with low-pass and high-pass noise. Conclusion: Results confirm the impairment of the lateralization and processing of binaural cues in the elderly differently.