Children’s articulatory constraints inferred from acoustic output: How some speech‐sound errors arise. Free

Our investigations of children’s speech acoustics indicate that normally developing children exhibit speech behavior that is not simply scaled adult behavior. Specific anatomical differences between children’s and adults’ vocal tracts cause these effects: For example, the size of the tongue in relation to the size of mouth decreases with age. The effects of these age‐related anatomical differences have been identified for preschool children as young as 1 year of age in phonetic segments, such as /ɹ/, /s/, and /∫/. These anatomic differences may lead children to produce subphonemic distinctions, as between /r/ and /w/ in English. Children’s anatomical features can also affect sounds generally not considered to be difficult for normally developing children to produce, such as syllable‐initial stops. We have noted children 12–18 months old producing intended /g/ that is often transcribed as /d/ by adult listeners. However, fronted velar /g/, which could be the result of a large tongue size in relation to palate size, exhibits subphonemic distinctions with children’s /d/. The behaviors arising from early anatomical features can be preserved into school age and be labeled as aberrant articulation.