In the present study we examined whether children with Developmental Dyscalculia (DD) exhibit a deficit in the so-called "Approximate Number System" (ANS). To do so, we examined a group of elementary school children who demonstrated persistent low math achievement over 4 years and compared them to typically developing (TD), aged-matched…

Programmatic, multidisciplinary research provided converging brain, genetic, and developmental support for evidence-based diagnoses of three specific learning disabilities based on hallmark phenotypes (behavioral expression of underlying genotypes) with treatment relevance: dysgraphia (impaired legible automatic letter writing, orthographic…

Two studies are presented that adopt a novel approach to determining whether verbal short-term memory performance is causally related to vocabulary acquisition in childhood. This involves examining whether verbal short-term memory measures are more closely related to the absolute level of individuals' vocabulary, or the rate at which vocabulary…

This study examined the effects of extra time on the reading comprehension performance of a heterogeneous group of adults with reading disabilities. Sixty-four adults participated. A clinic that assesses learning disabilities identified 22 as reading disabled, and 42 as normal readers. The 64 adults took a reading comprehension test under both…

Models of working memory were compared in 2 experiments as means of explaining variance in the comprehension of 95 skilled and 80 learning-disabled readers from grades 4 through 7. Results suggest that learning-disabled children's working memory problems are functionally related to higher order processes and not memory alone. (SLD)