Developmental dyslexia in Hindi readers: Is consistent sound-symbol mapping an asset in reading? Evidence from phonological and visuospatial working memory.

Phonological processing deficit is a hallmark of developmental dyslexia indicating a core cognitive dysfunction. Importance of working memory in reading and its association with the tasks measuring phonological processing is also debated in research. The present study investigates the role of working memory, phonological, and orthographic processing in Hindi-speaking dyslexic children (22 dyslexic and 23 control, of Grade 4). Hindi has a consistent symbol-sound mapping with an extensive list of visually complex graphemes. Although consistent symbol-sound mapping facilitates reading, graphemic complexity has its cost on memory. A range of tasks measuring phonological processing, working memory, and orthographic knowledge was designed and administered. Dyslexic children scored significantly lower than controls not only on working memory tasks but also on the tasks of phonological processing and orthographic knowledge. Moreover, the difference in working memory between dyslexic and normal children was more pronounced with increased task complexity. These results highlight complex relationships between working memory, phonological and orthographic processing together with visual attentional processing in Hindi, that contribute to the reading deficits encountered by children with dyslexia. Their respective contributions are considered in the discussion with some of the visual and phonological features of Hindi orthography and their associated effects in reading.

Variation in Vowel Duration Among Southern African American English Speakers.

PURPOSE: Atypical duration of speech segments can signal a speech disorder. In this study, we examined variation in vowel duration in African American English (AAE) relative to White American English (WAE) speakers living in the same dialect region in the South to characterize the nature of systematic variation between the 2 groups. The goal was to establish whether segmental durations in minority populations differ from the well-established patterns in mainstream populations. METHOD: Participants were 32 AAE and 32 WAE speakers differing in age who, in their childhood, attended either segregated (older speakers) or integrated (younger speakers) public schools. Speech materials consisted of 14 vowels produced in hVd-frame. RESULTS: AAE vowels were significantly longer than WAE vowels. Vowel duration did not differ as a function of age. The temporal tense-lax contrast was minimized for AAE relative to WAE. Vowels produced by females were significantly longer than vowels produced by males for both AAE and WAE. CONCLUSIONS: African American speakers should be expected to produce longer vowels relative to White speakers in a common geographic area. These longer durations are not deviant but represent a typical feature of AAE. This finding has clinical importance in guiding assessments of speech disorders in AAE speakers.