title: The EEG response to photic stimulation is not increased in alcohol-related seizures.
abstract: OBJECTIVE
  To investigate the occipital EEG response to 18 and 24Hz photic stimulation (the H-response) in alcohol-related seizures (ARS).
  
  
  METHODS
  Twenty-two ARS patients, 15 of whom had a withdrawal seizure (WS) were compared with patients with recent seizures of other causes: 21 patients with epilepsy, and 30 Alcohol Use Disorders Identification Test (AUDIT) negative patients with other seizures. EEG from 37 out-patients with epilepsy and 79 sciatica patents served as patient-controls. The spectral amplitude around 18 and 24Hz and a new photic H-ratio (24/18Hz relative amplitude) was calculated.
  
  
  RESULTS
  The H-ratio was significantly reduced in the ARS group compared to the sciatica group. H-ratio reduction correlated with the AUDIT score in ARS patients (p=0.02). No differences between WS and non-WS patients were found for H-response variables.
  
  
  CONCLUSIONS
  A dose-response relationship between AUDIT and the photic response H-ratio was observed in ARS patients. The EEG-driving response to 24Hz flashes was not increased in ARS.
  
  
  CONCLUSIONS
  The relative decrease in 24Hz photic response in ARS reflected drinking severity. The H-ratio is a candidate biomarker for ARS on the group level, although the moderate effect size precludes its use in individual patients.
authors.affiliation: Department of Neurology and Clinical Neurophysiology, St. Olavs Hospital, Norway; Norwegian University of Science and Technology, Trondheim, Norway. trond.sand@ntnu.no
authors.forename: Trond
authors.initials: T
authors.lastname: Sand
authors.forename: Marte
authors.initials: M
authors.lastname: Bjørk
authors.forename: Geir
authors.initials: G
authors.lastname: Bråthen
authors.forename: Eylert
authors.initials: E
authors.lastname: Brodtkorb
authors.forename: Ralf Peter
authors.initials: RP
authors.lastname: Michler
authors.forename: Gunnar
authors.initials: G
authors.lastname: Bovim
mesh_terms: D000328:Adult; D000368:Aged; D020270:Alcohol Withdrawal Seizures / Q000175:diagnosis* / Q000503:physiopathology*; D004569:Electroencephalography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010775:Photic Stimulation / Q000379:methods*; D012640:Seizures / Q000175:diagnosis / Q000503:physiopathology