Formant transition duration and place perception in misarticulating children and adolescents

Abstract

The explanation of articulatory problems as an output speech disorder does not preclude the possibility that auditory processing problems are associated. Identification of brief auditory spectral cues in a place-of-articulation continuum was studied in children with articulation problems. First, it was shown that formant transition durations smaller than 20·0 ms dramatically decreased phonemic identification rates for alveolar stop consonants in control subjects. Identification tasks based on two place-of-articulation continua /pαk/-/tαk/ with F2/F3 transition durations of 52 and 20 ms were administered to groups of misarticulating children and adolescents and two control groups (children and adults). For all subject groups there was poorer phonetic processing with shorter transition durations of F2 and F3. The misarticulating subjects demonstrated poorer phonetic processing of formant transitions than did the control subjects. Shortening F2/F3 transition duration did not differentially influence perceptual behaviour between the experimental and the control groups. In determining the causal link between perception and production, an explanation of perception preceding production was favoured. It was argued that, in addition to assessing the specificity between perception and production mechanisms, assessment of perception of formant transitions may have potential as a clinical tool for evaluating phonetic processing.

Key Words:

• speech perception
• articulation
• formant transitions
• apraxia of speech
• phonetic processing