Abstracts

Rationale: Cognitive impairments are commonly reported in children with temporal lobe epilepsy (TLE). While some pediatric investigations have documented both material specific and lateralizing findings, others have have not supported these notions. In contrast, the adult TLE literature is replete with studies demonstrating material specificity and lateralization. Moreoever, recent adult studies have suggested that language tasks, such as confrontational naming, may have particular relevance. We conducted a study to examine the lateralizing utility of intelligence, material specific memory, and language measures for children with temporal lobe epilepsy. Methods: Thirty children with temporal lobe epilepsy were divided into two groups: 18 children with left TLE and 12 children with right TLE. Seizure focus was determined by electroencephalogram. All children completed a comprehensive neuropsychological evaluation including standardized measures of intelligence, memory, and language. Measures included the Wechsler Intelligence Scale for Children-IV, Wide Range Assessment of Memory and Learning, Test of Memory and Learning, Peabody Picture Vocabulary Test, and the Test of Word Finding. Mean age at the time of evaluation was 13 years for both right and left TLE groups. The right and left TLE groups did not differ significantly with respect to age of onset or seizure frequency in the preceding 3 months. Children with intelligence scores below 70 were excluded. Results: A series of t-tests was performed for measures of Verbal and Performance intelligence, immediate and delayed verbal and visual-spatial memory, and language. Neither Verbal IQ nor Performance IQ score differentiated the TLE groups, with both performing in the Average range. Similarly, no group differences were found on measures of verbal memory, including immediate and delayed recall of a word list, a series of stories, and paired associates. Right and left TLE groups did not differ with respect to immediate and delayed recall of visual-spatial material, including spatial location and memory for faces. In contrast, group differences were noted on a measure of language development (t = 2.37, p = .03) with the left temporal lobe group performing lower than the right TLE group and below age-expected levels. Children with left TLE, as a group, also performed poorly on a word finding task and lower than the right TLE group, although the discrepancy did not reach significance. Conclusions: This study suggests that pediatric TLE is not associated with lateralized or material specific memory deficits. Moreover, VIQ and PIQ had no lateralizing significance. In contrast, measures of specific language functions appear to have a role in differentiating left and right TLE groups, with left TLE demonstrating deficits in these areas.