title: Functional connectivity MR imaging of the language network in patients with drug-resistant epilepsy.
abstract: OBJECTIVE
  Subtle linguistic dysfunction and reorganization of the language network were described in patients with epilepsy, suggesting the occurrence of plasticity changes. We used resting state FC-MRI to investigate the effects induced by chronic epilepsy on the connectivity of the language-related brain regions and correlated it with language performance.
  
  
  METHODS
  FC-MRI was evaluated in 22 right-handed patients with drug-resistant epilepsy (11 with LE and 11 with RE) and in 12 healthy volunteers. Neuropsychological assessment of verbal IQ was performed. Patients and controls underwent BOLD fMRI with a verb-generation task, and language function was lateralized by an LI. Intrinsic activity fluctuations for FC analysis were extracted from data collected during the task. Six seeding cortical regions for speech in both hemispheres were selected to obtain a measure of the connectivity pattern among the language networks.
  
  
  RESULTS
  Patients with LE presented atypical language lateralization and an overall reduced connectivity of the language network with respect to controls. In patients with both LE and RE, the mean FC was significantly reduced within the left (dominant) hemisphere and between the 2 hemispheres. In patients with LE, there was a positive correlation between verbal IQ scores and the left intrahemispheric FC.
  
  
  CONCLUSIONS
  In patients with intractable epilepsy, FC-MRI revealed an overall reduction and reorganization of the connectivity pattern within the language network. FC was reduced in the left hemisphere regardless of the epileptogenic focus side and was positively correlated with linguistic performance only in patients with LE.
authors.affiliation: Department of Radiology, Catholic University of Rome, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Pravatà
authors.forename: C
authors.initials: C
authors.lastname: Sestieri
authors.forename: D
authors.initials: D
authors.lastname: Mantini
authors.forename: C
authors.initials: C
authors.lastname: Briganti
authors.forename: G
authors.initials: G
authors.lastname: Colicchio
authors.forename: C
authors.initials: C
authors.lastname: Marra
authors.forename: C
authors.initials: C
authors.lastname: Colosimo
authors.forename: A
authors.initials: A
authors.lastname: Tartaro
authors.forename: G L
authors.initials: GL
authors.lastname: Romani
authors.forename: M
authors.initials: M
authors.lastname: Caulo
mesh_terms: D000293:Adolescent; D000328:Adult; D000927:Anticonvulsants / Q000627:therapeutic use; D001921:Brain / Q000503:physiopathology*; D004351:Drug Resistance; D004827:Epilepsy / Q000150:complications / Q000188:drug therapy / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007806:Language Disorders / Q000150:complications / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009415:Nerve Net / Q000503:physiopathology*; D009434:Neural Pathways / Q000503:physiopathology; D009473:Neuronal Plasticity; D055815:Young Adult
chemical_list: D000927:Anticonvulsants