title: The effect of topiramate on cognitive fMRI.
abstract: OBJECTIVE
  Topiramate (TPM) is known to cause language impairment in healthy volunteers and patients with epilepsy. We assessed the effects of TPM on functional language networks in both patients with focal epilepsies and healthy controls using functional magnetic resonance imaging (fMRI).
  
  
  METHODS
  We obtained fMRI data in 24 controls and 35 patients with frontal lobe epilepsy using a simple verbal fluency (VF) paradigm. Eight of the 35 patients were treated with TPM in polytherapy. We compared cognitive task related activations and de-activations in patients taking TPM with patients taking other AEDs and healthy controls. In a longitudinal pilot study with VF-fMRI paradigm, we studied two patients with focal epilepsies twice, prior to starting and on stable doses of TPM, two patients twice, before and after tapering TPM completely and two healthy controls twice, before and after single doses of 200mg TPM.
  
  
  RESULTS
  Cross sectional analyses of VF-fMRI showed a reduction in the task-related deactivation of the default mode network (DMN) in patients taking TPM. The longitudinal study corroborated these findings as both chronic administration and a single dose of TPM were associated with impaired categorical verbal fluency and disruption of task-related deactivations.
  
  
  CONCLUSIONS
  Similar neuropsychological and fMRI findings in patients and healthy controls indicate a specific effect of TPM in default mode network areas that may be essential components of the language network. Our preliminary data suggest a mechanism by which TPM impairs cognitive processing during language function and highlights the sensitivity of fMRI to detect the effects of AEDs on cognitive brain networks.
authors: Department of Neurology, University of Campinas, Campinas, Brazil. yasuda.clarissa@gmail.com
authors: Clarissa Lin
authors: CL
authors: Yasuda
authors: Maria
authors: M
authors: Centeno
authors: Christian
authors: C
authors: Vollmar
authors: Jason
authors: J
authors: Stretton
authors: Mark
authors: M
authors: Symms
authors: Fernando
authors: F
authors: Cendes
authors: Mitul A
authors: MA
authors: Mehta
authors: Pamela
authors: P
authors: Thompson
authors: John S
authors: JS
authors: Duncan
authors: Matthias J
authors: MJ
authors: Koepp
mesh_terms: D000328:Adult; D000927:Anticonvulsants / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D003071:Cognition / Q000187:drug effects* / Q000502:physiology; D003430:Cross-Sectional Studies; D004828:Epilepsies, Partial / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D005632:Fructose / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D000077236:Topiramate; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000927:Anticonvulsants; D000077236:Topiramate; D005632:Fructose