Study gives insight into underlying causes of specific learning disabilities

Up to 10 per cent of the population is affected by specific learning disabilities (SLDs), such as dyslexia, dyscalculia and autism, translating to two or three pupils in every classroom, a new study has found.

Led by Professor Brian Butterworth, a Professorial Fellow at the University of Melbourne's School of Psychological Sciences and Emeritus Professor of cognitive neuropsychology at University College London, the study gives insight into the underlying causes of specific learning disabilities and how to tailor individual teaching and learning for individuals and education professionals.

The study found children are frequently affected by more than one learning disability and that specific learning disabilities co-occur more often than expected.

For example, in children with attention-deficit or hyperactivity disorder, 33 to 45 per cent also suffer from dyslexia and 11 per cent from dyscalculia, a learning disability in mathematics.

Professor Butterworth said the results showed there were many neurological development disorders that result in learning disabilities, even in children of normal or even high intelligence.

Specific learning disabilities arise from atypical brain development with complicated genetic and environmental factors, causing such conditions as dyslexia, dyscalculia, attention-deficit/hyperactivity disorder, autism spectrum disorder and specific language impairment.

As part of the study, Professor Butterworth and colleague Yulia Kovas have summarised what is known about SLD's neural and genetic basis to help clarify how these disabilities develop, helping improve teaching for individual learners, and also training for school psychologists, clinicians and teachers.

The study suggests causes of SLDs are due to difficulties processing speech, language and numbers at a cognitive level. From a neurological basis, evidence suggests each SLD is associated with an abnormality in a distinct neural network. A single neurophysiological cause may affect distinct regions in the brain, affecting an individual's learning ability.

"We are also finally beginning to find effective ways to help learners with one or more SLDs, and although the majority of learners can usually adapt to the one-size-fits-all approach of whole class teaching, those with SLDs will need specialised support tailored to their unique combination of disabilities," he said.