A comparison of acoustic and perceptual changes in children’s productions of American English /r/

Abstract

Speech-language pathologists rely primarily on their perceptual judgments when evaluating whether children have made progress in speech sound therapy. Speech sound perception in normal listeners has been characterized as largely categorical, such that slight articulatory changes may go unnoticed unless they reach a specific acoustic signature assigned to a different category. While perception may be categorical, acoustic phenomena are largely measured in continuous units, meaning that there is a potential mismatch between the two methods of recording change. Clinicians, using perceptual categorization, commonly report that some children make no progress in therapy, yet acoustically, the children’s productions may be shifting toward acceptable acoustic characteristics. Using subtle changes in the acoustic signal during therapy could potentially prevent these clients from being discharged due to a perceived lack of progress. This poster evaluates acoustic changes compared to perceptual changes in children’s productions of the American English phoneme /r/ after receiving speech therapy using ultrasound supplemented with telepractice home practice. Preliminary data indicate that there are significant differences between participants’ acoustic values of /r/ and perceptual ratings by clinicians.