Investigating autonomic arousal and auditory motor control mechanisms across health and disease
OA Version
Citation
Abstract
Current investigations of speech production and auditory motor control mechanisms are limited by specificity in scope and paradigms bound to the laboratory environment. Despite attempts to isolate certain speech-related behaviors, heterogeneity exists in the research, especially when clinical populations are the focus of study, making it difficult to draw group-level conclusions and apply findings to the clinical setting. We propose to take a holistic approach to understand speech while leveraging variability to investigate individualistic characteristics that may contribute to certain speech production and auditory motor control behavior across health and disease. In studies 1 and 2 we utilized altered auditory feedback and physiological measures of the autonomic nervous system during cognitive loading tasks to understand the role of autonomic arousal in sensorimotor adaptation of suprasegmental (study 1) and segmental (study 2) aspects of speech in adults with typical speech. We also investigated a range of speech acoustic measures relating to auditory-perceptual aspects of speech in a cognitive loading task without altered auditory feedback to compare how changes in sensorimotor adaptation relate to these downstream changes in speech production in response to increased cognitive demand. We found that autonomic arousal was related to increased sensorimotor adaptation of suprasegmental and segmental features of speech, which suggests a potential role for state-based involvement in these higher-order processes. We also found that changes in sensorimotor adaptation of voice were related to changes in fundamental frequency during running speech without altered auditory feedback, indicating a potential relationship between speech adaptation and production mechanisms when cognitive resources are taxed. In study 3, we used electrodermal measures of autonomic activity and acoustic measures related to auditory-perceptual features of speech in a range of cognitively stressful speaking tasks to investigate the role of autonomic arousal in vocal hyperfunction. We found no effect of group on autonomic measures, indicating typical autonomic regulation in speakers with VH, compared to controls. We found significant effects of autonomic arousal on acoustic measures, demonstrating a role for arousal in speech. In study 4 we used altered auditory feedback, initial production variability, and within-production change in acoustic variance to investigate auditory feedback control in persons with Parkinson’s disease. We compared reflex responses from the altered auditory feedback paradigm with the measures of acoustic variability to determine if these more ecologically valid features of speech could reliably predict auditory feedback control mechanisms. We found no relationship in the suprasegmental features of speech; however, we found that reflex responses and initial production variability were related in the segmental features in speakers with and without Parkinson’s disease. More research is necessary to validate this result and explore the potential mechanism driving the relationship between speech stability and reliance on auditory feedback control in older adults. Through these studies, we implemented a multifaceted approach for understanding speech production and adaptation and investigated individual acoustic variability as a factor in auditory feedback control mechanisms.
Description
2025