Cortical dysfunction as an aetiological factor in learning disability.
This study examines the relationship between learning disability, EEG changes, and events in the life history of the individual child which could cause cortical damage or dysfunction. One hundred children with learning disability were compared with 100 age- and sex-matched normal children identified by random selection. Each child underwent routine EEG studies. Abnormalities were detected in 71 of the learning-disabled group and in 29 of the controls. The incidence of abnormal pregnancy was 31% in children with learning disability and 10% in controls. Neonatal complications occurred in 29 learning-disabled children as opposed to 13 controls. Seventeen learning-disabled children had experienced seizures and 5 had a history of meningitis; comparable figures in the control series were 7 and 2 respectively. Nine learning-disabled children had a history of severe illness as opposed to 3 children in the control series. The results of this study indicate that a significant relationship exists between learning disability and a variety of circumstances associated with insults to the immature brain. These insults may account for the cortical dysfunction suggested by psychometric and EEG studies.