November 21, 2013
Brain Imaging Helps Distinguish Two Similar Learning Disorders
April Flowers for redOrbit.com - Your Universe Online
The first anatomical evidence that the brains of children with a nonverbal learning disability may develop differently than the brains of other children has been discovered by a Michigan State University researcher. Nonverbal learning disability (NVLD) has long been considered a "pseudo" diagnosis.
The study findings, published in Child Neuropsychology, could someday help educators and clinicians better distinguish between and treat children with Asperger syndrome, a form of high functioning autism, and NVLD. The two conditions are often confused with one another.
“Children with nonverbal learning disabilities and Asperger’s can look very similar, but they can have very different reasons for why they behave the way they do,” said Jodene Fine, assistant professor of school psychology in MSU’s College of Education.
More appropriate intervention strategies could be developed with a deeper understanding of the biological differences in children with learning and behavioral challenges.
Children with NVLD tend to have below average math skills and difficulty solving visual puzzles, although they have normal language skills. Many of these children also show difficulty understanding social cues, leading scientists to argue that NVLD is related to high functioning autism. The current study suggest that this may not be so.
Fine worked with Kayla Musielak, an MSU doctoral student in school psychology to study about 150 children between the ages of 8 and 18. The research team used MRI scans of the participants' brains to find that the children with NVLD had smaller spleniums than children diagnosed with other learning disorders such as Asperger's and ADHD, as well as children who had no learning disorders.
The splenium is part of the corpus callosum, a thick band of fibers in the brain that connects the left and right hemispheres of the brain. This region facilitates communication between the two sides, and the posterior part of the corpus callosum serves the areas of the brain related to visual and spatial functioning.
In a second phase of the study, the participants' brain activity was analyzed after being shown videos while in the MRI, portraying both positive and negative examples of social interaction. For example, a positive event could include a child opening a desired birthday present with a friend, while a negative event could include a child being teased by other children.
The brains of children with NVLD responded differently to the social interactions than the brains of children with high functioning autism, or HFA. This suggests that the neural pathways that underlie those behaviors may be different.
“So what we have is evidence of a structural difference in the brains of children with NVLD and HFA, as well as evidence of a functional difference in the way their brains behave when they are presented with stimuli,” Fine said.
More research is needed to better understand how nonverbal learning disability fits into the family of learning disorders, Fine said, however, that her findings present “an interesting piece of the puzzle.”
“I would say at this point we still don’t have enough evidence to say NVLD is a distinct diagnosis, but I do think our research supports the idea that it might be,” she said.