title: Imaging seizure activity: a combined EEG/EMG-fMRI study in reading epilepsy.
abstract: OBJECTIVE
  To characterize the spatial relationship between activations related to language-induced seizure activity, language processing, and motor control in patients with reading epilepsy.
  
  
  METHODS
  We recorded and simultaneously monitored several physiological parameters [voice-recording, electromyography (EMG), electrocardiography (ECG), electroencephalography (EEG)] during blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) in nine patients with reading epilepsy. Individually tailored language paradigms were used to induce and record habitual seizures inside the MRI scanner. Voxel-based morphometry (VBM) was used for structural brain analysis. Reading-induced seizures occurred in six out of nine patients.
  
  
  RESULTS
  One patient experienced abundant orofacial reflex myocloni during silent reading in association with bilateral frontal or generalized epileptiform discharges. In a further five patients, symptoms were only elicited while reading aloud with self-indicated events. Consistent activation patterns in response to reading-induced myoclonic seizures were observed within left motor and premotor areas in five of these six patients, in the left striatum (n = 4), in mesiotemporal/limbic areas (n = 4), in Brodmann area 47 (n = 3), and thalamus (n = 2). These BOLD activations were overlapping or adjacent to areas physiologically activated during language and facial motor tasks. No subtle structural abnormalities common to all patients were identified using VBM, but one patient had a left temporal ischemic lesion.
  
  
  CONCLUSIONS
  Based on the findings, we hypothesize that reflex seizures occur in reading epilepsy when a critical mass of neurons are activated through a provoking stimulus within corticoreticular and corticocortical circuitry subserving normal functions.
authors: Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, Queen Square, London, United Kingdom.
authors: Afraim
authors: A
authors: Salek-Haddadi
authors: Thomas
authors: T
authors: Mayer
authors: Khalid
authors: K
authors: Hamandi
authors: Mark
authors: M
authors: Symms
authors: Oliver
authors: O
authors: Josephs
authors: Dominique
authors: D
authors: Fluegel
authors: Friedrich
authors: F
authors: Woermann
authors: Mark P
authors: MP
authors: Richardson
authors: Uta
authors: U
authors: Noppeney
authors: Peter
authors: P
authors: Wolf
authors: Matthias J
authors: MJ
authors: Koepp
mesh_terms: D000328:Adult; D001921:Brain / Q000503:physiopathology; D001931:Brain Mapping; D004292:Dominance, Cerebral / Q000502:physiology; D004562:Electrocardiography; D004569:Electroencephalography; D004576:Electromyography; D020195:Epilepsy, Reflex / Q000175:diagnosis / Q000503:physiopathology*; D005071:Evoked Potentials / Q000502:physiology; D005152:Facial Muscles / Q000503:physiopathology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000503:physiopathology; D009415:Nerve Net / Q000503:physiopathology; D009474:Neurons / Q000502:physiology; D010100:Oxygen / Q000097:blood*; D012660:Semantics; D012815:Signal Processing, Computer-Assisted; D014705:Verbal Behavior / Q000502:physiology; D055815:Young Adult
chemical_list: D010100:Oxygen