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The assessment of active language lateralization in infants and toddlers is challenging. It requires an imaging tool that is unintimidating, quick to setup, and robust to movement, in addition to an engaging and cognitively simple language processing task. Functional Transcranial Doppler Ultrasound (fTCD) offers a suitable technique and here we report on a suitable method to elicit active language production in young children. The 34-second “What Box” trial presents an animated face “searching” for an object. The face “finds” a box that opens to reveal a to-be-labelled object. In a sample of 95 children (1 to 5 years of age), 81% completed the task—32% with ≥10 trials. The task was validated (ρ = 0.4) against the gold standard Word Generation task in a group of older adults (n = 65, 60-85 years of age), though was less likely to categorize lateralization as left or right, indicative of greater measurement variability. Existing methods for active language production have been used with 2-year-old children while passive listening has been conducted with sleeping 6-month-olds. This is the first active method to be successfully employed with infants through to pre-schoolers, forming a useful tool for populations in which complex instructions are problematic. [ABSTRACT FROM AUTHOR]

In typically developing (TD) individuals, behavioral and event-related potential (ERP) studies suggest that audiovisual (AV) integration enables faster and more efficient processing of speech. However, little is known about AV speech processing in individuals with autism spectrum disorders (ASD). This study examined ERP responses to spoken words to elucidate the effects of visual speech (the lip movements accompanying a spoken word) on the range of auditory speech processing stages from sound onset detection to semantic integration. The study also included an AV condition, which paired spoken words with a dynamic scrambled face in order to highlight AV effects specific to visual speech. Fourteen adolescent boys with ASD (15-17 years old) and 14 age- and verbal IQ-matched TD boys participated. The ERP of the TD group showed a pattern and topography of AV interaction effects consistent with activity within the superior temporal plane, with two dissociable effects over frontocentral and centroparietal regions. The posterior effect (200-300?ms interval) was specifically sensitive to lip movements in TD boys, and no AV modulation was observed in this region for the ASD group. Moreover, the magnitude of the posterior AV effect to visual speech correlated inversely with ASD symptomatology. In addition, the ASD boys showed an unexpected effect (P2 time window) over the frontocentral region (pooled electrodes F3, Fz, F4, FC1, FC2, FC3, FC4), which was sensitive to scrambled face stimuli. These results suggest that the neural networks facilitating processing of spoken words by visual speech are altered in individuals with ASD. Autism Res 2011,4:xxx-xxx. © 2011 International Society for Autism Research, Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

In typically developing (TD) individuals, behavioral and event-related potential (ERP) studies suggest that audiovisual (AV) integration enables faster and more efficient processing of speech. However, little is known about AV speech processing in individuals with autism spectrum disorders (ASD). This study examined ERP responses to spoken words to elucidate the effects of visual speech (the lip movements accompanying a spoken word) on the range of auditory speech processing stages from sound onset detection to semantic integration. The study also included an AV condition, which paired spoken words with a dynamic scrambled face in order to highlight AV effects specific to visual speech. Fourteen adolescent boys with ASD (15-17 years old) and 14 age- and verbal IQ-matched TD boys participated. The ERP of the TD group showed a pattern and topography of AV interaction effects consistent with activity within the superior temporal plane, with two dissociable effects over frontocentral and centroparietal regions. The posterior effect (200-300 ms interval) was specifically sensitive to lip movements in TD boys, and no AV modulation was observed in this region for the ASD group. Moreover, the magnitude of the posterior AV effect to visual speech correlated inversely with ASD symptomatology. In addition, the ASD boys showed an unexpected effect (P2 time window) over the frontocentral region (pooled electrodes F3, Fz, F4, FC1, FC2, FC3, FC4), which was sensitive to scrambled face stimuli. These results suggest that the neural networks facilitating processing of spoken words by visual speech are altered in individuals with ASD., (Copyright © 2011, International Society for Autism Research, Wiley-Liss, Inc.)