title: fMRI evidence that precision ophthalmic tints reduce cortical hyperactivation in migraine.
abstract: BACKGROUND
  Certain patterns can induce perceptual illusions/distortions and visual discomfort in most people, headaches in patients with migraine, and seizures in patients with photosensitive epilepsy. Visual stimuli are common triggers for migraine attacks, possibly because of a hyperexcitability of the visual cortex shown in patients with migraine. Precision ophthalmic tints (POTs) are claimed to reduce perceptual distortions and visual discomfort and to prevent migraine headaches in some patients. We report an fMRI visual cortical activation study designed to investigate neurological mechanisms for the beneficial effects of POTs in migraine.
  
  
  METHODS
  Eleven migraineurs and 11 age- and sex-matched non-headache controls participated in the study using non-stressful and stressful striped patterns viewed through gray, POT, and control coloured lenses.
  
  
  RESULTS
  For all lenses, controls and migraineurs did not differ in their response to the non-stressful patterns. When the migraineurs wore gray lenses or control coloured lenses, the stressful pattern resulted in activation that was greater than in the controls. There was also an absence of the characteristic low-pass spatial frequency (SF) tuning in extrastriate visual areas. When POTs were worn, however, both cortical activation and SF tuning were normalized. Both when observing the stressful pattern and under more typical viewing conditions, the POTs reduced visual discomfort more than either of the other two lenses.
  
  
  CONCLUSIONS
  The normalization of cortical activation and SF tuning in the migraineurs by POTs suggests a neurological basis for the therapeutic effect of these lenses in reducing visual cortical hyperactivation in migraine.
authors.affiliation: Department of Radiology, Michigan State University, East Lansing, MI 48824, USA. jie@rad.msu.edu
authors.forename: Jie
authors.initials: J
authors.lastname: Huang
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Zong
authors.forename: Arnold
authors.initials: A
authors.lastname: Wilkins
authors.forename: Brian
authors.initials: B
authors.lastname: Jenkins
authors.forename: Andrea
authors.initials: A
authors.lastname: Bozoki
authors.forename: Yue
authors.initials: Y
authors.lastname: Cao
mesh_terms: D003116:Color; D005139:Eyeglasses; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007909:Lenses; D008279:Magnetic Resonance Imaging; D008881:Migraine Disorders / Q000503:physiopathology* / Q000517:prevention & control; D010775:Photic Stimulation; D014793:Visual Cortex / Q000503:physiopathology*