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Limited evidence for early indicators of childhood apraxia of speech (CAS) precludes reliable diagnosis before 36 months, although a few prior studies have identified several potential early indicators. We examined these possible early indicators in 10 toddlers aged 14-24 months at risk for CAS due to a genetic condition: 7q11.23 duplication syndrome (Dup7). Phon Vocalisation analyses were conducted on phonetic transcriptions of each child's vocalisations during an audio-video recorded 30-minute play session with a caregiver and/or a trained research assistant. The resulting data were compared to data previously collected by Overby from similar-aged toddlers developing typically (TD), later diagnosed with CAS (LCAS), or later diagnosed with another speech sound disorder (LSSD). The Dup7 group did not differ significantly from the LCAS group on any measure. In contrast, the Dup7 group evidenced significant delays relative to the LSSD group on canonical babble frequency, volubility, consonant place diversity, and consonant manner diversity and relative to the TD group not only on these measures but also on canonical babble ratio, consonant diversity, and vocalisation structure diversity. Toddlers with Dup7 also demonstrated expressive vocabulary delay as measured by both number of word types orally produced during the play sessions and primary caregivers' responses on a standardised parent-report measure of early expressive vocabulary. Examining babble, phonetic, and phonotactic characteristics from the productions of young children may allow for earlier identification of CAS and a better understanding of the nature of CAS.

Childhood apraxia of speech (CAS) is a paediatric motor speech disorder. We investigated the lexical tone perception and production abilities of children with CAS and the relationships between the two. Three children with CAS, aged between 3;7 and 5;8, were given the Cantonese Tone Identification Test (CANTIT) and the Hong Kong Cantonese Articulation Test (HKCAT) for assessment of tone perception and production, respectively. Accuracy and error patterns were investigated based on their performance on the two tests. Correlation analysis was performed on children's perception and production scores. Two children scored at the lowest rank on the CANTIT, while one child obtained a Z score of 0. All children scored three standard deviations below the mean on the HKCAT. No statistical differences were found among the six tones with respect to perception accuracy, H (5) = 3.731, p = 0.589. Error analysis showed that children with CAS demonstrated more confusion on perceiving tones compared with TD peers. There were no main effects for task ( F (1,2) = 0.040, p = 0.859) or tone (F(5,10 = 0.997, p = 0.467); nor were there task or tone interaction effects on perception versus production accuracy ( F (5,10) = 1.772, p = 0.206). Tone perception and production accuracy were not significantly correlated ( r 2  = 0.181, p = 0.078). Tone perception deficits were evident in two out of three children with CAS, while all children had lexical tone production difficulties. In this small sample, tone production was more universally affected than tone perception.

Phonological process analysis was carried out using a 40-word imitation task with 30 11;6-14;6 year old Kannada-speaking persons with Down syndrome in comparison with 15 non-verbal mental age matched typically developing children. Percentages of occurrence were significantly higher for the Down syndrome group with certain exceptions. Some phonological processes were observed only in the Down syndrome group. Kannada is a non-Indo European language spoken in the southern Indian state of Karnataka that has not had much research attention, especially with respect to persons with communication disorders. This paper highlights the phonological processes observed in school-aged persons with Down syndrome, some of which are similar to those observed in English and Dutch (cluster reduction, stopping, gliding, consonant harmony) and others that differ owing to differences in Kannada's phonology (e.g. retroflex fronting, degemination). The study gives a cross-linguistic perspective to the study of phonological processes in Down syndrome.