Professor Orly Rubinsten and colleagues found that methylphenidate affects the arithmetic performance of children in different ways, but its effects are not only on children with ADHD. When they received methylphenidate, the active ingredient in Ritalin, children had higher correct responding on problems requiring them to follow a series of steps than when they didn’t receive the drug; in contrast, there were no differences between drug and no-drug conditions on simpler tasks. The effects occurred for children with dyscalculia, less math problems, or no math problems.
Methylphenidate has Differential Effects on Numerical Abilities in ADHD Children with and without Co-Morbid Mathematical Difficulties
Authors: Orly Rubinsten, Anne-Claude Bedard, Rosemary Tannock
doi: 10.2174/1874350100801010011
Abstract:
Objective. To investigate effects of methylphenidate (MPH) on numerical performance in children with Attention- Deficit/Hyperactivity Disorder (ADHD) with and without concurrent math difficulties. Method. Data were analyzed from three groups of children with ADHD, who varied in arithmetic abilities. Groups were matched for IQ and reading abilities and classification was based on ICD-10 criteria, using scores on a standardized arithmetic achievement test. Thus, we identified one group with severe difficulties in arithmetic (ADHD+Developmental Dyscalculia; DD), second group with more general and less severe difficulties in arithmetic (ADHD+Mathematical Disabilities; MD), and a third group with good arithmetic abilities (ADHD). All children completed a 10-minute arithmetic task involving subtraction problems, during an acute, randomized, placebo-controlled cross-over trial with three dose levels of methylphenidate (10mg, 15mg, 20mg). Results. (1) Both ADHD+MD and ADHD+DD were impaired in using strategies that implicate working memory (i.e., borrowing). However, only the ADHD+DD were impaired in using implicit knowledge of quantities (i.e., doing simple subtractions). (2) MPH improved all children’s performance of arithmetic procedures (borrowing) that involves working memory, but had no effect on basic numerical skills that involves understanding of quantities. Conclusions. We show clear dissociation of MPH functions: it improves working memory functions but does not improve specific cognitive functions such as quantity manipulation. Moreover, MPH shows decreased efficacy for arithmetic performance in ADHD+DD, highlighting the need for additional intervention in this subgroup.
Keywords: Methylphenidate, developmental dyscalculia, ADHD
Affiliation: Neurosciences and Mental Health Research Program, Research Institute, The Hospital for Sick Children, 555 University Ave., Toronto, Ontario, Canada.
The study appeared in The Open Psychology Journal and the entire article is available for free via the Open Journal initiative.
Liz Ditz has a post noting today’s status as “International Dyscalculia Awareness Day, Today.” Read it here.
Although the paper was published several years ago, it is worth noting. It may not be news, but it forms part of the fabric one has to consider in thinking about the nature of dyslexia. Read this in the context of other stories (e.g., this one) about genetic bases for dyslexia.
A candidate gene for developmental dyslexia encodes a nuclear tetratricopeptide repeat domain protein dynamically regulated in brain
Mikko Taipale, Nina Kaminen, Jaana Nopola-Hemmi, Tuomas Haltia, Birgitta Myllyluoma, Heikki Lyytinen, Kurt Muller, Minna Kaaranen, Perttu J. Lindsberg, Katariina Hannula-Jouppi, and Juha Kere
Communicated by Albert de la Chapelle, Ohio State University, Columbus, OH, June 24, 2003 (received for review December 23, 2002)
Approximately 3–10% of people have specific difficulties in reading, despite adequate intelligence, education, and social environment. We report here the characterization of a gene, DYX1C1 near the DYX1 locus in chromosome 15q21, that is disrupted by a translocation t(2;15)(q11;q21) segregating coincidentally with dyslexia. Two sequence changes in DYX1C1, one involving the translation initiation sequence and an Elk-1 transcription factor binding site (–3G A) and a codon (1249G T), introducing a premature stop codon and truncating the predicted protein by 4 aa, associate alone and in combination with dyslexia. DYX1C1 encodes a 420-aa protein with three tetratricopeptide repeat (TPR) domains, thought to be protein interaction modules, but otherwise with no homology to known proteins. The mouse Dyx1c1 protein is 78% identical to the human protein, and the nonhuman primates differ at 0.5–1.4% of residues. DYX1C1 is expressed in several tissues, including the brain, and the protein resides in the nucleus. In human brain, DYX1C1 protein localizes to a fraction of cortical neurons and white matter glial cells. We conclude that DYX1C1 should be regarded as a candidate gene for developmental dyslexia. Detailed study of its function may open a path to understanding a complex process of development and maturation of the human brain.
Link to the PNAS materials.
V. Dion Haynes
Washington Post
Dear Mr. Haynes,
In your article about changes in the administration of special education in Washington (DC, US), entitled “Special-Ed Getting New Computer System, Staff” appearing 27 February 2008 on page B04,” you used the term “Learning Disabilities” as a generic reference for students with various other, legally recognized disabilities. Here is an extract (my underlining):
For years, city and school officials have criticized programs provided by the D.C. schools’ special education office, which serves 9,400 students with physical or learning disabilities. The school system spends about $137 million a year on private school tuition for about 2,400 children it cannot serve in the public schools.
Specific Learning Disabilities is a specific category of disability under US federal law (Public Law 108-446, 108th Congress), and it is expressly differentiated from mental retardation, emotional disturbance, and other disabilities. It is not a generic term and should not be used to refer to multiple categories of disabilities. Although it may seem trivial to some, this difference is important to many. Using the term “learning disabilities” as a generic obscures important differences in students and may even undermine efforts by parents and educators to seek services for students who have learning disabilities, emotional or behavioral disorders, intellectual disabilities, autism, and speech-language disorders (among others).
I hope that this note is helpful. Thank you for your reporting of the substantive content in your article (which I’ve covered elsewhere).
John Wills Lloyd, Ph.D.
Editor, LD Blog
Professor, University of Virginia
Lehigh University will offer a conference on special education law in May under the title, “Special Education Law: A Roadmap of Reality, Resolution, and Remedies.” The special one-day meeting, which is the 36th annual installment in the series, features many interesting topics including a keynote by Perry Zirkel, noted authority on legal issues in Learning Disabilities and related areas of special education.
The conference is scheduled for 9 May 2008 and will be held in Bethlehem (PA, US). Link to the agenda for the conference.
Brain Gym (Skeptic’s Dictionary)
Wheeeheee! Over on the Skeptic’s Dictionary, Robert T. Carroll has a take-down and pin of Brain Gym. The contemporary incarnation of some ideas that were thoroughly discredited in Learning Disabilities in the 1970s, Brain Gym is making something of a splash. Shoot, it even appeared in one of my Curry School colleague’s classes for a while, as I understand.
Professor Carroll’s indictment of Brain Gym presents a good opportunity to make an important point. The problem with Brain Gym and many of its siblings is not that the activities might not be worthwhile, it’s that the advocates over-reach so substantially. Shoot, I’m glad to advocate that we teach kids who might fit the clumsy category how to walk, move, dance, play basketball, and etc. I just don’t want people to be sold a bill of goods about how doing so will improve those children’s reading, etc.
Read Professor Carroll’s analysis. Need info on the research about the benefits of perceptual-motor training? Here’s a link to a meta-analysis.