title: Reduced language connectivity in pediatric epilepsy.
abstract: OBJECTIVE
  Functional connectivity (FC) among language regions is decreased in adults with epilepsy compared to controls, but less is known about FC in children with epilepsy. We sought to determine if language FC is reduced in pediatric epilepsy, and examined clinical factors that associate with language FC in this population.
  
  
  METHODS
  We assessed FC during an age-adjusted language task in children with left-hemisphere focal epilepsy (n = 19) compared to controls (n = 19). Time series data were extracted for three left regions of interest (ROIS) and their right homologues: inferior frontal gyrus (IFG), middle frontal gyrus (MFG), and Wernicke's area (WA) using SPM8. Associations between FC and factors such as cognitive performance, language dominance, and epilepsy duration were assessed.
  
  
  RESULTS
  Children with epilepsy showed decreased interhemispheric connectivity compared to controls, particularly between core left language regions (IFG, WA) and their right hemisphere homologues, as well as decreased intrahemispheric right frontal FC. Increased intrahemispheric FC between left IFG and left WA was a positive predictor of language skills overall, and naming ability in particular. FC of language areas was not affected by language dominance, as the effects remained only when examining participants with left language dominance. Overall FC did not differ according to duration of epilepsy or age of onset.
  
  
  CONCLUSIONS
  FC during a language task is reduced in children, similar to findings in adults. In specific, children with left focal epilepsy demonstrated decreased interhemispheric FC in temporal and frontal language connections and decreased intrahemispheric right frontal FC. These differences were present near the onset of epilepsy. Greater FC between left language centers is related to better language ability. Our results highlight that connectivity of language areas has a developmental pattern and is related to cognitive ability.
authors.affiliation: Children's National Medical Center, Washington, District of Columbia, U.S.A.
authors.forename: Leigh N
authors.initials: LN
authors.lastname: Sepeta
authors.forename: Louise J
authors.initials: LJ
authors.lastname: Croft
authors.forename: Lauren A
authors.initials: LA
authors.lastname: Zimmaro
authors.forename: Elizabeth S
authors.initials: ES
authors.lastname: Duke
authors.forename: Virginia K
authors.initials: VK
authors.lastname: Terwilliger
authors.forename: Benjamin E
authors.initials: BE
authors.lastname: Yerys
authors.forename: Xiaozhen
authors.initials: X
authors.lastname: You
authors.forename: Chandan J
authors.initials: CJ
authors.lastname: Vaidya
authors.forename: William D
authors.initials: WD
authors.lastname: Gaillard
authors.forename: Madison M
authors.initials: MM
authors.lastname: Berl
mesh_terms: D001931:Brain Mapping / Q000379:methods; D002648:Child; D002675:Child, Preschool; D004827:Epilepsy / Q000503:physiopathology*; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology*; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007223:Infant; D007802:Language; D007807:Language Tests; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D013702:Temporal Lobe / Q000503:physiopathology*
keywords: Functional neuroimaging; Neuropsychological assessment; Seizures