Speech sound errors of Mandarin-speaking preschool children with co-occurring speech sound disorder and developmental language disorder

The development of speech output processing skills in Greek-speaking children

There is a growing body of literature on phonological development in Greek-speaking children, either typically developing (TD) or with speech sound disorders (SSD). In this paper, a cross-sectional longitudinal approach was used to investigate the development of speech output processing skills in TD Greek-speaking preschool-aged children. Moreover, a group of Greek-speaking children with SSD were assessed to identify potential loci of impairment in atypical development. The developmental study involved two groups: group 1 (n = 16) aged 3;0-3;5 years and group 2 (n = 22) aged 4;6-5;0 years, assessed at three assessment points six months apart. Children with SSD (n = 15) aged 5;6-6;0 years were assessed to be compared with performance of group 2 TD children (at the third assessment point). Assessment tasks included (a) a picture naming task, (b) a task of real word repetition and (c) a task of nonword repetition. A strong time effect was found in both groups of TD children in the development of speech output processing abilities. Performance accuracy was higher on tasks including real words than nonwords; children performed more accurately on repetition rather than spontaneous naming of real words; repetition accuracy on 2-3 syllables items was significantly better than on 4-5 syllables items. Children with SSD were outperformed by TD children of the same age in all assessment tasks; lexicality and word length effect were found in the clinical group. Findings from the present study may be used as a starting point to diagnose children with speech production difficulties in Greece.

Developmental language disorder in Chinese children: A systematic review of research from 1997 to 2022

Developmental language disorder (DLD) is one of the most common neurodevelopmental disorders. The influences of DLD on language development have been delineated in detail in English. The same is not true for Chinese, a group of Sinitic languages with distinct typological features that may modify the profile of DLD crosslinguistically. We conducted a systematic search of English and Chinese journal databases and reviewed 59 studies on the manifestations of DLD in Chinese. Methodological quality appraisal of the literature revealed several areas of improvement to enhance transparency and replicability. A bibliometric analysis indicated a steep growth trajectory of this literature. Examination of the participant selection and diagnostic criteria revealed limitations and calls for the development of assessment tools and increased knowledge of evidenced-based diagnostic practice. Areas of deficits demonstrated by Chinese children with DLD were synthesized qualitatively and discussed in light of the literature on clinical markers of DLD in English.

Receptive vocabulary, memory span, and speech articulation in Pakistani children with developmental language disorders

This study aimed to find the association of receptive vocabulary in the development of speech and language among school-going children (4-13 years) with language disorders. On the basis of non-verbal receptive vocabulary and percentage correct consonants (PCC) scores, children from public schools in Punjab, Pakistan with speech and language issues were separated into three groups; Speech sound disordered (SSD, N = 15), Language Impaired (LI) comorbid with SSD (N = 42) and typically developed (TD, N = 15). Urdu version of Peabody picture vocabulary test, fourth edition (U-PPVT-4), Digit memory test (DMT), and Test for assessment of articulation and phonology in Urdu (TAAPU) were used to assess non-verbal receptive vocabulary, Short-term memory (STM), Working memory (WM), and SSD. Correlation and regression analyses were performed to find the association of receptive vocabulary with other measures used. Receptive vocabulary, STM, WM, omission, substitution, and PCC scores were significantly different (p < 0.01) when compared among LI+SSD, SSD, and TD groups. Regression analysis showed that receptive vocabulary was significantly associated with STM and WM in the LI+SSD group. A positive correlation was found between the U-PPVT-4 standard score with STM and WM for LI+SSD and SSD groups. Our findings in Urdu-speaking children suggested that STM and WM were less developed in children with speech and language impairments. Moreover, children with speech and language deficits not only had weaker receptive vocabulary but also attention should be given to improving STM and WM that contribute to LI.

Perception of the /t/-/k/ contrast by Mandarin-speaking children with Speech Sound Disorders

Mandarin-speaking children with speech sound disorders (SSD) often show difficulties in producing alveolar and velar plosives contrasts (e.g., /t/ vs. /k/). But it remains unclear whether such phonological disorder correlates with the perception of the contrast between alveolar and velar plosives. The present study assessed whether Mandarin-speaking children with SSD who substituted [t] for /k/ in production could perceptually distinguish between /t/ and /k/, and compared their results with those from typically developing children (TDC) and typically adults (TA). We adopted a categorical perception paradigm with a /ta/-/ka/ continuum. The continuum included nine stimuli, which were synthesized from a naturally-produced /ta/. The SSD, TDC, and TA groups completed both identification and discrimination tasks that required perceptual judgment of individual stimulus and pairs of stimuli from the continuum. The results showed that the TDC and TA groups showed typical patterns of categorical perception in the continuum. But the SSD group only reached or was slightly above the chance level in the identification task and did not show significant difference among pairs of stimuli in the discrimination task. Their performance was significantly different from that of the TDC and TA groups and lacked typical patterns of categorical perception. The results suggested that their perception of /t/ vs. /k/ may be impaired. Considering the SSD group's speech errors, this perception defect may be a cause for their tendency of substituting [t] for /k/ in production.

Working memory span and receptive vocabulary assessment in Urdu speaking children with speech sound disorder

Emerging evidence suggests that impaired speech may be related to reduced working memory (WM). The current study aimed to validate and compare the influence of articulation, short-term memory (STM), WM, and receptive vocabulary abilities of Pakistani children with speech sound disorder (SSD; N = 50) versus typically developing (TD; N = 30) children aged 7-13 years. Assessments included the Test for Assessment of Articulation and Phonology in Urdu (TAAPU), Peabody Picture Vocabulary Test-4, translated to Urdu (U-PPVT-4), and Digit Memory Test (DMT) used to determine speech articulation, receptive vocabulary, and memory abilities respectively. The percentage correct consonants (PCC) score was used to divide the SSD group further into SSD severity groups. The TD and SSD groups significantly differed in performance on all tasks (p < 0.05). Moreover, the SSD severity groups showed significant differences (p < 0.0001) in performance on different components of TAAPU (total errors and substitution errors) and DMT tasks. However, the SSD severity groups did not show significant differences in performance on the U-PPVT-4. Correlational analyses indicate statistically significant correlations of PCC with STM, WM, and receptive vocabulary. Regression analyses suggested that both WM and STM contribute to speech intelligibility in children with SSD. Our findings in Urdu-speaking children support previous results in English-speaking children suggesting the articulation skills, receptive vocabulary, STM, and WM were less developed in children with SSD than in TD children.