Auditory temporal order and resolution in younger and older Maltese adults

Abstract

Recent studies are accruing support for the existence of auditory processing disorder in adults as a multifactorial condition underlying alterations in the auditory mechanisms and the brain. However, local research that evaluates age-related changes in temporal order and resolution is still very limited. This paper explores agerelated differences on non-speech measures of temporal order and resolution by investigating the performance of younger and older Maltese adults on four tests of temporal processing. The study also compares the four measures of temporal processing and explores their relationship. Sixteen younger adults (YA) aged between 18 and 25 years and 10 older adults (OA) aged between 60 and 74 years participated in the study. Temporal ordering, as measured by the Duration Pattern Test (DPT) and the Frequency Pattern Test (FPT), and temporal resolution, as measured by the Random Gap Detection Test (RGDT) and the Gaps-in-Noise Test (GIN), were evaluated. Results indicated that in comparison to OA, YA performed significantly better in all four tests. Thus, the OA group required more time to identify temporal changes in a stream of sound and were less able to label patterns of duration and frequency. With regards to the comparison between measures, while a statistically significant difference between the two tests of temporal resolution emerged, no significant difference between temporal order tests was revealed. A negative correlation between temporal order and resolution was established, indicating that a greater percentage of correct responses on temporal order tests was related to shorter gap detection thresholds on resolution tests. These findings tentatively suggest that the two subtypes of temporal measures may underlie common auditory processing abilities but may be influenced by the type of stimuli employed or the auditory processing mechanisms being assessed.