Doctor of Philosophy
Health and Rehabilitation Sciences
Oram Cardy, Janis
Separate lines of research have demonstrated relations between auditory temporal processing and language ability and between information processing speed and intelligence. Because these processes have rarely been studied in the same sample, it is unclear how auditory temporal processing and information processing speed may operate together and how they may relate to cognitive functions including language. The overarching aim of this dissertation was to integrate these lines of research to better understand whether auditory temporal processing has a unique relation with language, or whether it relates more broadly to language and other cognitive functions as a part of global information processing speed. Study 1 examined auditory temporal processing, information processing speed, language ability, and intelligence in 4-6 year olds (N=47). Results revealed that auditory temporal processing and information processing speed correlated with age and with each other, but previously identified correlations with language and intelligence were not supported. Results raised questions about the auditory temporal processing measure used, thus Study 2 involved a mixed methodological scoping review to disentangle behavioural measures and constructs of auditory temporal processing in the extant literature. The review identified five categories of tasks that reportedly measure six auditory temporal processing constructs. Study 3 was planned as a pilot of three, child-friendly auditory temporal processing tasks that were designed and programmed based on Study 3 results, using a sample of adults and investigating the same relations as Study 1. Data collection was interrupted by Covid-19, thus Study 3 was written as a pre-registration and Study 4 involved a feasibility assessment for measuring auditory temporal processing online. Results revealed that measuring auditory temporal processing online shows promise, but must first be tested to ensure accuracy, precision, and quality of stimuli in the specific context of the tasks being used due to the potential impact on millisecond level timing. Although the direction of this dissertation took a step back to disentangle questions outside of the original overall aim, the collective results return the field to a place where the original questions may be investigated with better clarity about important considerations that need to be made moving forward.
Summary for Lay Audience
The way in which we process the smallest pieces of incoming sound information that we hear (auditory temporal processing) may influence how easily children learn language. Previous research has shown that auditory temporal processing and language development may be related, but what remains unknown is whether language development is specifically related to processing sounds or to the speed of processing information in general. The goal of this dissertation was to investigate how language and intelligence relate to auditory temporal processing and information processing speed. Study 1 measured auditory temporal processing, overall processing speed, language ability, and intelligence in 47 4-6 year old children. Results revealed that auditory temporal processing and processing speed related to age and to each other, but were not related to language ability and intelligence as previously found. Study 2 reviewed the literature to clarify how auditory temporal processing is defined and measured, and found five categories of auditory temporal processing tasks that reportedly measure six specific types of auditory temporal processing. With this information, Study 3 involved the design and programming of three child-friendly auditory temporal processing tasks to investigate the same relations that were studied in Study 1. Because Study 3 was interrupted due to Covid-19, Study 4 reviewed the literature to examine the possibility of measuring auditory temporal processing online. Results revealed that measuring auditory temporal processing online may be possible, but must first be tested using the specific tasks to ensure timing is not impacted by factors such as computer hardware and software. Overall, this dissertation aimed to understand how the processing of sensory information relates to the development of language, and this remains the aim going forward with a deeper understanding about how auditory temporal processing is and can be measured.
Smyth, Rachael E., "The Relation of Auditory Temporal Processing to Language Development and Other Cognitive Processes: Methodological and Conceptual Considerations" (2021). Electronic Thesis and Dissertation Repository. 7635.