The Electroencephalogram in Learning Disability: Special Emphasis on Interictal Epileptiform Discharges
Abstract
This study dealt with the electroencephalograms (EEGs) of 187 children with learningdisability. Special attention was given to interictal epileptiform discharges. The patients who had interictal epileptiform discharge in their EEG was labeled as spike group, in contrast with those without such activity as the control group. In the whole group, 45.9% were completely normal and an additional 10.6% had positive spikes as the only finding. Epileptiform activity was seen in 32%, mainly focal (mostly centrotemporal or occipital) less often generalized, with bilaterally synchronous spike and waves complexes seen in 13 children. Slow wave abnormalities (mainly frontal or temporal), nearly always mild in degree, were seen mainly in the spike group. These different findings suggest that learning disability is a condition often with organic changes in the form of EEG abnormality, at times with epileptiform activity that could contribute to a deficit in learning.
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