Visual motion processing in migraine: Enhanced motion after-effects are related to display contrast, visual symptoms, visual triggers and attack frequency.
Background Visual after-effects are illusions that occur after prolonged viewing of visual displays. The motion after-effect (MAE), for example, is an illusory impression of motion after viewing moving displays: subsequently, stationary displays appear to drift in the opposite direction. After-effects have been used extensively in basic vision research and in clinical settings, and are enhanced in migraine. Objective The objective of this article is to assess associations between ( 1 ) MAE duration and visual symptoms experienced during/between migraine/headache attacks, and ( 2 ) visual stimuli reported as migraine/headache triggers. Methods The MAE was elicited after viewing motion for 45 seconds. MAE duration was tested for three test contrast displays (high, medium, low). Participants also completed a headache questionnaire that included migraine/headache triggers. Results For each test contrast, the MAE was prolonged in migraine. MAE duration was associated with photophobia; visual triggers (flicker, striped patterns); and migraine or headache frequency. Conclusions Group differences on various visual tasks have been attributed to abnormal cortical processing in migraine, such as hyperexcitability, heightened responsiveness and/or a lack of intra-cortical inhibition. The results are not consistent with hyperexcitability simply from a general lack of inhibition. Alternative multi-stage models are discussed and suggestions for further research are recommended, including visual tests in clinical assessments/clinical trials.
1 Department of Psychological Sciences, Birkbeck, University of London, UK.
Alex J
AJ
Shepherd
1 Department of Psychological Sciences, Birkbeck, University of London, UK.|2 Department of Psychology, City University, London, UK.
Ramiro M
RM
Joly-Mascheroni
D000328:Adult; D005260:Female; D006801:Humans; D007088:Illusions / Q000209:etiology* / Q000502:physiology*; D008297:Male; D008881:Migraine Disorders / Q000503:physiopathology*; D009039:Motion Perception / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D055815:Young Adult
Migraine; adaptation; contrast; cortical processing; flicker; motion after-effect; motion perception; photophobia; stripes; visual perception; visual triggers