Abstracts

Rationale: Children with intractable epilepsy are at risk for memory impairment. This study examined parent report of their child s everyday memory function before and after epilepsy surgery. It also investigated a number of variables to identify potential predictors of change in everyday memory after surgery. Methods: Parents reported on their child s everyday memory function using a 27-item rating scale, before and approximately one year after surgery (n = 43; mean age = 12.3 years). A non-surgical comparison group (n = 19; mean age 13.2 years) was evaluated at similar points in time. The location of epileptogenic tissue, age of seizure onset, duration of epilepsy, number of antiepileptic medications and premorbid IQ were investigated as possible predictive variables for everyday memory performance. Results: The two groups did not differ on age, sex distribution, age at seizure onset, number of anti-epileptic medications, or handedness. An ANOVA on questionnaire scores revealed an interaction between time and laterality. Left hemisphere resections resulted in a mild decline in everyday memory scores whilst right hemisphere resections resulted in an improvement. These changes for both groups were, however, quite modest in degree. There was no change over time in the comparison group. The main predictors of change in everyday memory in the surgical group were age at baseline such that older children showed the most improvement, and duration of epilepsy such that individuals who had epilepsy for longer periods of time showed the most improvement. There were no significant changes related to seizure outcome in the surgical group. Conclusions: The present study is the first to demonstrate that everyday memory function in children may be differentially affected by resections from the left and right hemispheres of the brain. There appears to be some plasticity involved for everyday memory function, as indicated by correlations with age and duration in the surgical group.