Accelerated long-term forgetting and academic achievement in children with idiopathic generalised epilepsy

Abstract

Recently, children with IGE were found to have a more rapid rate of forgetting of newly-learned information over long delays (days or weeks) relative to shorter delays (up to 30 min): accelerated long-term forgetting (ALF). We examined whether ALF persists over time in children with IGE, and which factors predict the outcome. A longitudinal prospective study of 18 children with IGE and 29 healthy controls (HC) measured intelligence, working memory and verbal and visual learning (involving recall after short, 20 to 30-min delays), in addition to verbal recall at long (7 day) delays. At both time points children with IGE recalled fewer words than HC at 7-days, but not 2-min and 30-min delays suggesting that ALF does not resolve over time. Younger age of seizure onset, more severe epilepsy at baseline and taking antiepileptic drugs (AED) at follow-up were related with fewer words recalled at 7 days. We also set out to test academic skills in children with IGE, determine whether ALF or other cognitive factors contributes to academic difficulties in children with IGE. Standardised tests of reading, spelling and numerical operations, phonological processing and memory were used. Children with IGE obtained significantly lower scores than HC children on tests of word reading and numerical operations, but not on a spelling test. In children with IGE, scores on the tests of word reading and numerical operations were not related to recall of information after long delays, but were related to standardised memory test scores. Earlier age of seizure onset was significantly correlated with lower scores on a word reading test. Our findings confirm that ALF exists and persists in children with IGE. Children with IGE are also at risk of poorer academic performance than healthy children in word reading and arithmetic, but ALF is not related to these academic difficulties.