Monday, May 19, 2025
5/19/2025
Quantitatively Characterizing the Speech Motor Skillsets of Individual Speakers - PROJECT SUMMARY The overall goal of this project is to develop and test a neurocomputational model characterizing the speech motor skills of individual talkers in a way that captures key speech motor control processes, namely auditory feedback control, somatosensory feedback control, and feedforward control. In addition to assessing the model’s fits to behavioral data, we will also test hypotheses concerning the relationships between neural measures and model parameters. Our goal will be achieved through a tight coupling of computational modeling and behavioral, neurostimulation, and neuroimaging experiments, organized into two specific aims involving the same three participant cohorts: adults with persistent developmental stuttering, adults with dyslexia, and neurotypical adults. Aim 1: Assess the specificity and reliability of model parameter fits to individual subjects This aim assesses our model’s ability to characterize the speech motor skillsets of a broad range of participants who will perform a series of behavioral experiments probing speech motor control mechanisms. Each participant will perform two behavioral sessions on different days, during which their responses to reflexive and adaptive auditory and somatosensory perturbations applied during speech will be measured. Subject-specific model fits will be created for each protocol in each session, and the reliability of model parameter estimates across protocols and sessions will be assessed to verify the model’s ability to meaningfully account for individual differences. Predictions regarding group differences also will be tested, and computational modeling will be used to assess model fits and compare them to alternative control schemes. Aim 2: Identify neural correlates of individual-specific model parameters and assess their reliability This aim involves two studies that test predictions derived from our neurocomputational model. The first study uses magnetic resonance imaging to test for predicted correlations between neural measures (including structural and functional connectivity measures) and model parameters. The second uses transcranial direct current stimulation (tDCS) applied to hypothesized auditory and somatosensory feedback control centers to test predictions regarding the function of these centers and their relationship to model parameters. These experiments will provide crucial data regarding the neural subsystems underlying speech motor processes. Successful completion of our aims will result in the first quantitative, neuroanatomically grounded model that reliably characterizes the speech motor skillsets of individuals, including those with communication disorders, thereby constituting a crucial step toward translating cutting-edge science into individualized treatments for motor speech disorders. We will also determine how the motor skillsets of individuals with stuttering and dyslexia differ from those of neurotypical speakers. Finally, these studies will further clarify the relationships between brain function and speech motor behaviors characterized by the DIVA neurocomputational model.
HHS’ Tracking Accountability in Government Grants System (TAGGS) website provides access to detailed descriptions of grants, loans, aggregated direct payments and other types of financial assistance awarded by the HHS Operating Divisions (OPDIVs) and the Office of the Secretary Staff Divisions (STAFFDIVs).