Abstracts

Rationale: Children with Benign Childhood Epilepsy with Centrotemporal Spikes [BECTS] have rare ictal events, yet experience frequent interictal high-voltage centro-temporal spikes [CTS] induced by sleep. Despite a favorable prognosis, BECTS patients score in the low-normal range of neuropsychological tests, particularly in language (Northcott et al, 2005, Epilepsia 46: 924-930; Danielsson and Petermann 2009, Epilepsy Behav 16:646-651). Since CTS are frequent, it is unclear how real-time interictal CTS correlate with cognitive performance. In this study, we combined 24-hour EEG with neuropsychological testing to determine the relationship of interictal spikes with language testing scores.Methods: 11 children with newly diagnosed BECTS (5-11yo, 7F) were enrolled at Cincinnati Children s Hospital Medical Center. All were right-handed, monolingual native speakers of English, and naive to antiepileptic drug treatment. 11 controls (5-11yo, 5F) were matched by age, gender and socioeconomic status. 24-hour ambulatory EEG was obtained with simultaneous neuropsychological testing. CTS on the EEGs were marked as left, right, or bilateral by a trained epileptologist. Language outcomes were assessed via Clinical Evaluation of Language Fundamentals-4 [CELF-4] Composite scores, Comprehensive Test of Phonological Processing [CTOPP] Phonological Awareness and Rapid Naming Composite scores. Spearman correlation was utilized to associate CTS with neuropsychological test scores. Composite scores were compared via t-test between cohorts.Results: The groups did not differ significantly on CTOPP Rapid Naming or Phonological Awareness (both p>0.2). CELF-4 scores for BECTS patients were slightly lower than controls but also did not differ significantly (mean scores 98 and 104 respectively, p=0.18; see Vannest et al. 2013 for differences in CELF-4 scores in a larger cohort). The number of right CTS during testing and Rapid Naming scores showed a significant negative correlation (rs=-0.620, p=0.04). The number of left CTS during testing was also significantly negatively correlated with CTOPP Rapid Naming scores (rs=-0.677, p=0.02).Conclusions: A negative relationship between right-sided and left-sided real-time interictal CTS and Rapid Naming was observed. Rapid Naming requires efficient visual processing, retrieval of phonological components, and speech production. It is known that lateralization of CTS modifies aspects of language, with right-sided spikes affecting visuospatial skills and language processing, and left-sided spikes affecting phonology and speech production (Bedoin et al, 2006, Epilepsy Behav, 9:268-274). Frequency of CTS in right and left hemispheres during testing and its negative impact on performance suggest CTS directly affects cognitive function in BECTS. This finding suggests an opportunity to influence cognitive performance in children with BECTS through targeted complete elimination of CTS.