Abstracts

Rationale: It is known that children with epilepsy are at risk for neurocognitive deficits, and those with temporal/frontal lobe epilepsy are at increased risk for language impairment. Furthermore, early age of onset in the dominant hemisphere may result in atypical language lateralization (Helmstaedter et al, 1997), which can have significant implications for surgical outcome. Clinical experience in our setting suggests that bilingual children with epilepsy experience greater language deficits compared to their monolingual counterparts. Several studies have found that the functional brain organization of bilinguals and monolinguals have distinct and shared sites that support both languages (Lucas et al., 2004). However, little is known about the role that bilingualism plays with respect to the nature and degree of language difficulties in children with epilepsy. This retrospective study aims to examine the differences in monolingual and bilingual children diagnosed with epilepsy on language tasks. Methods: The sample included 24 children diagnosed with temporal or frontal lobe epilepsy who completed comprehensive evaluations. Two children were eliminated from the analyses due to comorbid diagnoses of Autism Spectrum Disorders, leaving 11 bilingual and 11 monolingual patients. Nine of the bilingual participants were bilingual English/Spanish, one was bilingual English/Korean, and one was bilingual English/Tagalog. There were no significant differences in age at, or time since diagnosis between the two groups. Expressive and receptive language abilities were assessed with standard validated language measures. Analyses were controlled for seizure foci. Results: Hierarchical regression analyses were conducted to evaluate whether bilingualism significantly predicted performance on language assessments above what is predicted by seizure foci. Bilingualism accounted for a significant proportion in variance of the standard scores on measures of expressive language, R2 change = .461, F(1, 7) = 6.967, p = .0165, suggesting that patients with similar seizure foci are likely to perform better on tests of expressive language if they are monolingual rather than bilingual. Bilingualism did not significantly predict performance on receptive language assessments. Conclusions: Results suggest that based on our small study sample, pediatric bilingual epilepsy patients demonstrate increased risk for language difficulties, particularly expressive language. As found in previous studies, age of second language acquisition may be an important mediator, particularly for receptive language (Dehaene et al., 1997). The functional neural organization of language in bilingual children with epilepsy needs to be examined to aid in pre-surgical evaluations and help predict post-surgical outcome. Gaining significance with such a small sample size in the present study is promising, and future research is indicated to better understand the neurocognitive, neurodevelopmental, and neuropathological processes involved in the developing bilingual child with epilepsy.