Impaired numerosity perception in developmental dyscalculia (low "number acuity") has been interpreted as evidence of reduced representational precision in the neurocognitive system supporting non-symbolic number sense. However, recent studies suggest that poor numerosity judgments might stem from stronger interference from non-numerical…

The present research is aimed at developing an educational program effective for the development of the concepts of perimeter and area in students with LD and testing this program. The study combined action research with quasi-experimental design involving experimental (LD) and comparison (non-LD) groups. The intervention program consisted of 12…

This study investigated whether a latent class of children with math difficulties (MD) or math learning disabilities (MLD) emerged within a heterogeneous sample of learners. A latent class analysis was computed on children (N = 447) in Grade 3 who were administered a battery of math, reading, and cognitive measures. The analysis yielded four…

Development of early math skill depends on a prerequisite level of cognitive development. Identification of specific cognitive skills that are important for math development may not only inform instructional approaches but also inform assessment approaches to identifying children with specific learning problems in math. This study investigated the…

Research has yet to make measurable progress toward understanding how to help students with math learning disabilities (MLDs) overcome their persistent difficulties. Prior research has traditionally framed MLDs as cognitive deficits and studied these deficits by analyzing failing students' errors. In this paper, we provide an alternative. We…

Experienced mental abacus (MA) users are able to perform mental arithmetic calculations with unusual speed and accuracy. However, it remains unclear whether their extraordinary gains in mental arithmetic ability are accompanied by an improvement in numerical processing efficiency. To address this question, the present study, using a numerical…

This study examined the relationship between cognitive abilities and math achievement within a sample of college students with learning disabilities (LD). The cognitive abilities were seven areas identified by Stratum II of the Cattell-Horn-Carroll (CHC) theory of cognitive abilities, in addition to the eighth area of Working Memory. Math…

Explanations of the marked individual differences in elementary school mathematical achievement and mathematical learning disability (MLD or dyscalculia) have involved domain-general factors (working memory, reasoning, processing speed, and oral language) and numerical factors that include single-digit processing efficiency and multidigit skills…

This study investigated the role of strategy instruction and working memory capacity (WMC) on word problem solving accuracy in children with (n = 100) and without (n = 92) math difficulties (MD). Within classrooms, children in Grades 2 and 3 were randomly assigned to one of four treatment conditions: verbal-only strategies (e.g., underlining…

Calculia is considered to be the ability of performing arithmetic operations, the preconditions for the development of mathematical skills in the complex functioning of psychological functions represented in neuro-anatomical systems, as well in the interaction with the environment. Problems in acquiring arithmetic skills can be described as…

Although current categories of learning disabilities include as specific disabilities calculation and mathematical problem solving [see IDEA reauthorization, 2004, Sec. 300.8(c)(10)], the majority of research focuses on calculation disabilities. Previous studies have shown, however, that deficits in word problem solving difficulties are persistent…

Turner syndrome is a common disorder with a prevalence of 1:2,500 live female births. Although not associated with mental retardation, there is an increased risk of learning difficulties in this population. In particular, mathematical learning difficulties among girls with Turner syndrome are prevalent, significant, and persistent. As such, the…

Interest in students who exhibit characteristics with difficulties in learning can be traced as far back as 1800. In order to better understand the complexities and causes of learning disabilities, many researchers (Bannatyne, 1968, 1974; Rugal, 1974) have investigated ways to better identify learners who struggle with academics. A strong argument…

Time taken to count stimuli was compared among three groups each composed of 22 elementary-aged children (with autism, with moderate learning difficulties, and normally developing). Results suggest that children with autism showed a tendency toward an analytic level of processing. While groups differed on measures of counting speeds, children…

Twenty-seven children (ages 7-10) with learning disabilities and 42 controls were tested on three different mathematics tasks. Significantly more controls abstracted composite unit structures suggestive of operational logic on modified nonverbal and associativity of length tasks. On a flash card task, children with learning disabilities achieved…