While most work in speech communication to date attempts to characterise average responses of homogeneous populations, the importance of explaining individual differences between subjects and test items is increasingly recognised. This is particularly relevant in the case of hearing loss or foreign-language ability, but differences exist too in working memory capacity or executive control, factors related to an aging population.
Project ID-1 aims to better characterise various types of hearing loss, based on estimates of sensitivity, cochlear compression, frequency selectivity, temporal resolution, intensity discrimination, cognitive capabilities, and their relation to performance in different speech intelligibility tests, including consonant identification and sentence recognition.
Project ID-2 examines how individual differences in auditory and cognitive abilities affect the integration of acoustic and lexical information during speech recognition.
The goal of Project ID-3 is to develop a battery of tests aimed at quantifying and developing theories about the depletion of central processing resources during speech perception in noise. The effect of noise on higher-order functions is notably understudied yet highly-relevant when considering individual performance, especially for older listeners or listeners operating in a non-native language.