Phonetic Testing and Acoustic Indices in the Assessment of Childhood Apraxia of Speech
Claudio Zmarich, Vincenzo Galatà
The phonetic test is an image-naming tool, transcribed into IPA, designed to measure phonetic abilities quickly and reliably. The new Early Childhood Phonetic Test (TFPI), intended for children aged between 18 and 47 months, enables the creation of phonetic inventories, the analysis of phonological processes and the calculation of indices such as the PCC. Although it would not be the gold standard for childhood apraxia of speech (CAS), studies show that the TFPI can highlight the phonological inconsistency typical of CAS, particularly as word complexity increases. The use of software such as Praat and Phon, and future integration of the TFPI into SpeechCatcher, automates and enhances these analyses. In a clinical setting, acoustic analysis represents an effective alternative to kinematic analysis. Key parameters include voice onset time (VOT), which is essential for consonant voicing, and «locus equations» (Lindblom & Sussman, 2012), which quantify anticipatory coarticulation through F2 values, providing objective data on the motor and articulatory planning of speech.
Keywords
CAS; Early childhood phonetic test; Praat; Phon; VOT; coarticulation; Locus equations.
