Early Indicators of Reading Disability
A longitudinal study reported by Finnish scientists presents compelling evidence that indicators of subsequent reading disability are present at birth. The research team examined two groups of children for over a decade. One group was designated “at-risk” for a reading disability based on the children having two first degree relatives with a reading disability. For example, a mother and a close relative of the mother. The other group of children were age-matched peers.
The children were initially examined shortly after birth (within 3-5 days) using a brain monitoring procedure called event-related potential (ERP). The children were presented with the sounds of consonant-vowel combinations and the ERPs measured the preferred hemisphere of the brain that was activated when the sounds were heard. The at-risk children showed a preference for processing the sounds in the right hemisphere of the brain whereas the control children showed a preference for left hemisphere processing. It should be noted that in the vast majority of individuals language processing occurs in the left hemisphere.The children were also examined using brain measuring techniques at 6 months of age. These measures showed differences between the groups in discriminating aspects of phonemes. Phonemes are the individual sounds that are combined to form words.
The researchers also collected additional measures as the children aged. These included measures of phonological awareness, letter identification, and ability to rapidly name familiar stimuli such as letters or numbers. Again, the researchers reported differences between the two groups on these measures.
All of the measures that differentiated between the groups as they matured turned out to be significant predicters of reading ability in the second grade.