A look at the other 90 per cent: Investigating British Sign Language vocabulary knowledge in deaf children from different language learning backgrounds

In this study we present new data on deaf children's receptive and expressive vocabulary knowledge in British Sign Language (BSL) from a sample consisting of children with deaf parents, children with hearing parents, and children with additional needs. Their performance on three BSL vocabulary tasks was compared with (previously reported findings from) a sample of deaf fluent signers. We use these data to assess the effects of some key demographic/ child variables on deaf signing children's vocabulary and discuss findings in the relation to the meaning of 'normative' data and samples for this heterogeneous population. Findings show no effect of the presence of additional disabilities on participants' scores for any of the three tasks. As expected, chronological age is the most significant factor in performance on all vocabulary tasks while the number of deaf relatives only becomes statistically significant for the form recall task. This study contributes to the field of sign language assessment by seeking to identify key variables in heterogeneity and how these variables affect signed vocabulary acquisition with the long-term objective of informing intervention

Does congenital deafness affect the structural and functional architecture of primary visual cortex?

Deafness results in greater reliance on the remaining senses. It is unknown whether the cortical architecture of the intact senses is optimized to compensate for lost input. Here we performed widefield population receptive field (pRF) mapping of primary visual cortex (V1) with functional magnetic resonance imaging (fMRI) in hearing and congenitally deaf participants, all of whom had learnt sign language after the age of 10 years. We found larger pRFs encoding the peripheral visual field of deaf compared to hearing participants. This was likely driven by larger facilitatory center zones of the pRF profile concentrated in the near and far periphery in the deaf group. pRF density was comparable between groups, indicating pRFs overlapped more in the deaf group. This could suggest that a coarse coding strategy underlies enhanced peripheral visual skills in deaf people. Cortical thickness was also decreased in V1 in the deaf group. These findings suggest deafness causes structural and functional plasticity at the earliest stages of visual cortex

Modeling of fast wave current drive experiments on DIII-D

Modeling of fast wave current drive experiments for D3-D has been improved to include calculation of target temperature profiles consistent with the D3-D database and more accurate modeling of the launched spectrum. The calculations indicate that a measurable current will be driven by fast wave in the near-term (30--200 kA). Modeling of the long-range goal of 2 MA non-inductive at high {beta} indicates the proposed 18 MW of rf power will be adequate. The optimum frequency for the intermediate scenario is 120 MHz; this frequency selection is also adequate for the long-term goals. 8 refs., 2 figs., 2 tabs

Verbal Problem-Solving Difficulties in Autism Spectrum Disorders and Atypical Language Development

Children with autism spectrum disorders (ASDs) adopt less efficient strategies than typically developing (TD) peers on the Twenty Questions Task (TQT), a measure of verbal problem-solving skills. Although problems with the TQT are typically associated with executive dysfunction, they have also been reported in children who are deaf, suggesting a role for atypical language development. To test the contribution of language history to ASD problem solving, TQT performance was compared in children with high-functioning autism (HFA), children with Asperger syndrome (AS) and TD children. The HFA group used significantly less efficient strategies than both AS and TD children. No group differences were evident on tests of question understanding, planning or verbal fluency. Potential explanations for differences in verbal problem-solving skill are discussed with reference to the development of inner speech and use of visual strategies in ASD

Design and performance of fast wave current drive systems in the ICRF

Experiments have begun on D3-D using the fast wave current drive (FWCD) phased antenna array. The array consists of four elements with slotted septa between them to reduce mutual coupling. The passive phasing/matching circuit developed for the launcher incorporates only five tuning elements and is driven by a single rf power supply. The system has successfully operated in the presence of plasma at power levels up to 1.25 MW, with {pi}/2 relative phasing, and approximately equal currents and voltages on all elements. Tuning algorithms that allow proper setting of all five elements within 1--2 shots have been developed. In addition, substantial modeling has been undertaken in support of the D3-D FWCD program. Loading calculations that take into account currents induced in the septa as well as other effects related to antenna geometry have been performed, and the results agree well with the observed data. A circuit model has been developed that, in combination with the loading calculations, allows the simulation of shot-to-shot matching for various tuning algorithms. 6 refs., 8 figs