title: Memory in frontal lobe epilepsy: an fMRI study.
abstract: OBJECTIVE
  Focal epilepsies are often associated with structural and functional changes that may extend beyond the area of seizure onset. In this study we investigated the functional anatomy of memory in patients with frontal lobe epilepsy (FLE), focusing on the local and remote effects of FLE on the networks supporting memory encoding.
  
  
  METHODS
  We studied 32 patients with drug-resistant FLE and 18 controls using a functional magnetic resonance imaging (fMRI) memory encoding paradigm.
  
  
  RESULTS
  During encoding of stimuli, patients with FLE recruited more widely distributed areas than healthy controls, in particular within the frontal lobe contralateral to the seizure onset. Normal memory performance was associated with increased recruitment of frontal areas, and conversely a poor performance was associated with an absence of this increased recruitment and decreased activation in mesial temporal lobe areas.
  
  
  CONCLUSIONS
  In patients with FLE, recruitment of wider areas, particularly in the contralateral frontal lobe, appears to be an effective compensatory mechanism to maintain memory function. Impaired hippocampal activation is relatively rare and, in turn, associated with poor recognition memory.
authors: Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, Queen Square, London, United Kingdom.
authors: Maria
authors: M
authors: Centeno
authors: Christian
authors: C
authors: Vollmar
authors: Jonathan
authors: J
authors: O'Muircheartaigh
authors: Jason
authors: J
authors: Stretton
authors: Silvia B
authors: SB
authors: Bonelli
authors: Mark R
authors: MR
authors: Symms
authors: Gareth J
authors: GJ
authors: Barker
authors: Veena
authors: V
authors: Kumari
authors: Pamela J
authors: PJ
authors: Thompson
authors: John S
authors: JS
authors: Duncan
authors: Mark P
authors: MP
authors: Richardson
authors: Matthias J
authors: MJ
authors: Koepp
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000098:blood supply* / Q000473:pathology; D001931:Brain Mapping; D017034:Epilepsy, Frontal Lobe / Q000150:complications*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders / Q000209:etiology* / Q000473:pathology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D021641:Recognition, Psychology; D055815:Young Adult
chemical_list: D010100:Oxygen