Abstracts

Rationale: Despite the high prevalence of memory impairment in children with epilepsy, surprisingly little is known about the verbal learning and memory (VLM) profiles of children with frontal lobe epilepsy (FLE) relative to children with temporal lobe epilepsy (TLE) and the impact of clinical and demographic variables. This study sought to provide a better understanding of the VLM patterns that might differentiate children with FLE from children with TLE and study the impact of variables that could potentially influence cognition (seizure laterality, age at seizure onset, age at assessment, number of antiepileptic drugs [AEDs]).Methods: Retrospective analyses of data from children with intractable TLE (n = 100) and FLE (n = 27) and unilateral seizure foci who completed standardized measures of VLM (Word List: Children’s Auditory Verbal Learning Test, Second Edition [CAVLT-2] and California Verbal Learning Test, Second Edition [CVLT-II]; Paired-Associates: Children’s Memory Scale [CMS] - Word Pairs [WP], Wechsler Memory Scale [WMS] - Verbal Paired Associates [VPA]). Comparisons were made between the VLM profiles of participants with TLE versus FLE epilepsy and those with right versus left seizure foci. Correlations among VLM indices and age at assessment, age at seizure onset, and number of AEDs were examined separately for TLE and FLE groups.Results: Mean intelligent quotients (IQ) and scores on both VLM tasks generally fell within the average range. Multivariate analyses yielded no significant differences overall in VLM between TLE and FLE groups; however, exploratory analyses revealed a significant group difference on Paired Associate total scores (p = .039, n2partial = .050) and a trend toward a significant group difference on learning (p = .062, n2partial = .041), both in favour of the FLE group. Although a significant main effect of seizure laterality on Word List Learning indices was found (p = .029, n2partial = .125) and inspection of the results revealed that this effect was consistently in favour of right seizure laterality, pairwise comparisons failed to reveal significant effects for specific indices. Older age at assessment was associated with better performance on a number of VLM indices for the TLE group, but in the FLE group, age was only related to fewer intrusion errors. Older age at seizure onset was associated with better associative learning for the TLE group, while younger age at seizure onset was associated with fewer intrusion errors for the FLE group.Conclusions: The VLM profiles of children with TLE and FLE epilepsy were similar and group means were within normative expectations. Right seizure laterality may represent a potential predictor of enhanced VLM. Improved memory monitoring (i.e., as indicated by fewer intrusions) was related to older age at assessment and younger age at seizure onset in the FLE group, while older age at both assessment and seizure onset was related to better encoding, retrieval, and monitoring processes for the TLE group.