Markers of auditory and language deficits in Down syndrome : a behavioural and electrophysiological study

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Audiovisual speech perception in children and adolescents with developmental dyslexia:No deficit with McGurk stimuli

Developmental dyslexia could, at least partially, reflect an underlying problem in forming audiovisual associations, such as between graphemes and phonemes. Some of the few studies testing people with reading difficulties on McGurk stimuli report less sensitivity to visual information, and worse processing of visual-only speech. In this study, we tested Dutch children (M =11.0 years) and adolescents (M = 13.7 years) with developmental dyslexia, and age-matched controls. Dyslexics and age-matched controls were similarly able to recognize the nonsense syllables “apa” and “aka” from hearing or seeing a speaker. Most critically, dyslexics and controls showed similar response patterns to McGurk stimuli, consisting of hearing “apa” combined with seeing a speaker say “aka”. Adolescents, however, perceived McGurk stimuli more often as /k/ and somewhat less often as /p/ than children, confirming earlier studies investigating age differences. Both groups did not differ in their number of fusion (/t/) responses. Concluding, audiovisual speech perception does not seem to be impaired in developmental dyslexia, if groups show similar unimodal speech perception

Children's use of evaluative devices in spoken and written narratives

This study investigated the development of evaluation in narratives from middle to late childhood, within the context of differentiating between spoken and written modalities. Two parallel forms of a picture story were used to elicit spoken and written narratives from fourth- and sixth-graders. It was expected that, in addition to an increase of evaluative devices with age, written narratives would exhibit a higher frequency and diversity as a result of the intrinsic differences between the two modalities. From a developmental perspective, the results showed that only few categories exhibited the expected increase with age. Qualitative analyses provided a fruitful method to illustrate developmental changes. The results further indicated that modality had the expected impact on the diversity, and on the frequency, of most categories of evaluative language. Specifically, markers of decontextualized language and categories with a high degree of syntactic complexity were prone to modality differences

De rol van executieve functies bij de ontwikkeling van schrijfvaardigheid

Executive functions (EF) refer to self-regulative processes that underlie goal-directed activities. While previous research has shown a strong relationship between EF and achievements in school, there is a paucity of empirical research that has examined how EF contribute to writing development in the upper elementary grades. This longitudinal study examined how EF predict development in narrative writing in these grades. Both in fourth and in sixth grade, children’s writing skills were assessed using a narrative picture-elicitation task. In addition, in fourth grade a battery assessing transcription skills, language skills, and EF was administered. The results showed that in fourth grade, EF contributed directly to the quality of the written narrative, and indirectly, with handwriting fluency functioning as a mediator. Furthermore, results revealed that EF in fourth grade predicted development of the syntactic complexity of the written narratives between fourth and sixth grade. The theoretical and educational implications of these results are discussed

Audiovisual temporal sensitivity in typical and dyslexia adult readers

Reading is an audiovisual process that requires the learning of systematic links between graphemes and phonemes. It is thus possible that reading impairments reflect an audiovisual processing deficit. In this study, we compared audiovisual processing in adults with developmental dyslexia and adults without reading difficulties. We focused on differences in cross-modal temporal sensitivity both for speech and for non-speech events. When compared to adults without reading difficulties, adults with developmental dyslexia presented a wider temporal window in which unsynchronized speech events were perceived as synchronized. No differences were found between groups for the non-speech events. These results suggests a deficit in dyslexia in the perception of cross-modal temporal synchrony for speech events

Replication of Seli, Risko, and Smilek (2016): Direct+ replication at Lancaster University

CREP direct+ replication of Seli, Risko, and Smilek (2016

Deficient response to altered auditory feedback in dyslexia

Although dyslexia is characterized by a deficit in phonological representations, the nature of this deficit is debated. Previously, it was shown that adults with dyslexia respond differently to online manipulations of auditory feedback. In the present study, we found that individual differences in reading and reading-related skills within a group of 30 children (10--13 years old) with dyslexia were associated with the response to altered feedback. The fractional anisotropy of the arcuate fasciculus/superior longitudinal fasciculus was not directly related to the response to altered feedback. This study corroborates that speech perception-production communication is important for phonological representations and reading

Lateralisation of auditory processing in Down syndrome: a study of T-complex peaks Ta and Tb

Contains fulltext : 128169.pdf (publisher's version ) (Open Access)It has long been argued that abnormal cerebral previous termlateralisationnext term might underlie the language problems that characterise previous termDownnext term syndrome, but to date only behavioural evidence has been provided. We used the previous termauditorynext term event-related potentials Ta and Tb of the T-complex to investigate lateralised previous termprocessingnext term of speech (vowels) and non-speech (simple and complex tones) sounds in children with previous termDownnext term syndrome and age-matched typically developing children. We also explored associations with speech and language abilities. Although changes in the Ta and Tb in response to increases in stimulus complexity and 'speechness' were similar across group, the Tb peak was delayed in children with previous termDownnext term syndrome across conditions. In addition, marked differences in the patterns of previous termlateralisationnext term of Ta latency and Tb amplitude were observed in children with previous termDownnext term syndrome, in response to both speech and non-speech sounds. No associations were found between Ta and Tb characteristics and speech and language abilities in children with DS