title: Deficient prepulse inhibition of blink reflex in migraine and its relation to allodynia.
abstract: OBJECTIVE
  Prepulse inhibition (PPI) of the blink reflex (BR) is a reduction in BR excitability due to a conditioning stimulus, reflecting sensory gating by brainstem structures. We aimed to analyze PPI changes during a painful episode in chronic or episodic migraine and its relation to allodynia, since abnormal brainstem filtering has been hypothesized in migraine pathophysiology.
  
  
  METHODS
  We included 20 patients with migraine during headache episode, and age- and gender-matched 22 healthy subjects. We recorded BR after unconditioned and conditioned supraorbital stimuli. For conditioned stimuli, we applied preceding subthreshold stimulus to the median nerve at wrist. The presence of PPI was compared between the two groups, as well as the specific BR parameters (latency, amplitude or area of R1 and R2 components) in unconditioned (test) and conditioned (PPI) paradigms.
  
  
  RESULTS
  In the patient group, seven (35%) patients did not have R2-PPI whereas all healthy subjects had R2-PPI (P=0.003). Healthy subjects displayed significantly increased R1 amplitude and reduced R2 amplitude and area after conditioned stimuli. In migraine patients, we observed significant reduction only in R2 amplitude. Logistic regression demonstrated that allodynia was independently related with the presence of PPI (beta: -0.535, P=0.021).
  
  
  CONCLUSIONS
  Our study provides evidence for sensory gating impairment at brainstem level in migraine headache, related to the presence of allodynia.
authors: Department of Neurology, Cerrahpaşa School of Medicine, Istanbul University, Istanbul, Turkey.
authors: Ugur
authors: U
authors: Uygunoglu
authors: Department of Neurology, Cerrahpaşa School of Medicine, Istanbul University, Istanbul, Turkey. Electronic address: draysegulgunduz@yahoo.com.
authors: Aysegul
authors: A
authors: Gunduz
authors: Department of Neurology, Cerrahpaşa School of Medicine, Istanbul University, Istanbul, Turkey.
authors: Harika Devrimsel
authors: HD
authors: Ertem
authors: Department of Neurology, Cerrahpaşa School of Medicine, Istanbul University, Istanbul, Turkey.
authors: Derya
authors: D
authors: Uluduz
authors: Department of Neurology, Cerrahpaşa School of Medicine, Istanbul University, Istanbul, Turkey.
authors: Sabahattin
authors: S
authors: Saip
authors: Department of Neurology, Cerrahpaşa School of Medicine, Istanbul University, Istanbul, Turkey.
authors: Baki
authors: B
authors: Goksan
authors: Department of Neurology, Cerrahpaşa School of Medicine, Istanbul University, Istanbul, Turkey.
authors: Aksel
authors: A
authors: Siva
authors: Department of Neurology, Cerrahpaşa School of Medicine, Istanbul University, Istanbul, Turkey.
authors: Nurten
authors: N
authors: Uzun
authors: Department of Neurology, Cerrahpaşa School of Medicine, Istanbul University, Istanbul, Turkey.
authors: Feray
authors: F
authors: Karaali-Savrun
authors: Department of Neurology, Cerrahpaşa School of Medicine, Istanbul University, Istanbul, Turkey.
authors: Meral
authors: M
authors: Kızıltan
mesh_terms: D000328:Adult; D001767:Blinking; D001933:Brain Stem / Q000503:physiopathology; D005260:Female; D006801:Humans; D006930:Hyperalgesia / Q000150:complications / Q000503:physiopathology*; D008297:Male; D008881:Migraine Disorders / Q000150:complications / Q000503:physiopathology*; D065808:Prepulse Inhibition
keywords: Allodynia; Allodynie; Blink reflex; Inhibition du réflexe de clignement; Migraine; Prepulse inhibition; Réflexe de clignement