The relationship between inexperienced listeners' perceptions and acoustic correlates of children's /r/ productions

This study examined inexperienced listeners' perceptions of children's naturally produced /r/ sounds with reference to levels of accuracy determined by consensus between two expert clinicians. Participants rated /r/ sounds as fully correct, distorted or incorrect/non-rhotic. Second and third formant heights were measured to explore the relationship between acoustic cues and perceptual judgments. Inexperienced listeners' agreement was greater for correct productions than for distorted or incorrect/non-rhotic productions. In addition, inexperienced listeners' differentiation of intermediate versus fully incorrect /r/ had lower sensitivity and specificity relative to an acoustically defined threshold than experienced listeners' classification. These findings are consistent with results of previous studies highlighting the difficulty in identifying gradations of correctness in misarticulated /r/, and they suggest that this ability may be influenced by clinical experience. Additionally, all listeners were noted to be more consistent in rating vocalic /r/ than consonantal /r/. Implications for clinician training and treatment planning are discussed.