The locus of flicker adaptation in the migraine visual system: A dichoptic study

Abstract

Background-Flickering light has been shown to sensitize the migraine visual system at high stimulus contrast while elevating thresholds at low contrast. The present study employs a dichoptic psychophysical paradigm to ask whether the abnormal adaptation to flicker in migraine occurs before or after the binocular combination of inputs from the two eyes in the visual cortex.

Enhanced Motion Aftereffects in Migraine Are Related to Contrast Sensitivity: Implications for Models of Differences in Precortical/Cortical Function

“…The current results suggest an anomaly in early motion processing pathways in migraine that is linked with those pathways underlying contrast sensitivity. It provides further evidence for differences in visual processing that begin early, potentially starting at the level of the retina, which have consequences for performance on other tasks that putatively examine cortical processing (see also prior reports 14,34,36 ). Thus, differences in precortical and cortical visual pathways are implicated in the pathophysiology underlying migraine.…”

Clinical impact of migraine for the management of glaucoma patients

“…Temporal tuning of visual field defects. Migraine patients typically report aversion and discomfort to flickering stimuli (Karanovic et al, 2011;Thabet et al, 2013;Wilkinson et al, 2008).…”

“…Convergent evidence from psychophysical studies shows that temporally modulated stimuli have a particular potential to uncover visual deficits in migraine (Antal et al, 2005;Battista et al, 2010Battista et al, , 2011Ditchfield et al, 2006;Drummond and Anderson, 1992;Karanovic et al, 2011;McKendrick and Badcock, 2003, 2004a, 2004b, 2004cMcKendrick et al, 2000McKendrick et al, , 2001Shepherd, 2006;Shepherd et al, 2012;Thabet et al, 2013), including flickering stimuli that are thought to be processed pre-cortically (Coleston et al, 1994;McKendrick and Badcock, 2003;McKendrick et al, 2001). Such abnormal responses to flickering stimuli in migraine might be relevant to the potential link between migraine and glaucoma, given evidence for temporal processing anomalies in glaucoma (Casson et al, 1993;Eisner and Samples, 1991;O'Hare et al, 2012).…”

“…2003; Karanovic et al, 2011;Khalil, 1991;Marcus and Soso, 1989;Shepherd, 2000;Thabet et al, 2013;Wilkinson et al, 2008) or cortical inhibitory/excitatory imbalance (Vecchia and Pietrobon, 2012). Nevertheless, the presence of normal pattern ERG yet abnormal pattern VEP in migraine may be helpful in clinically distinguishing the cause for visual dysfunction with respect to migraine or glaucoma.…”

“…Further, evidence for the cortical pathophysiology of migraine is being pieced together by knowledge gained from advanced structural and functional neuroimaging (Schwedt et al, 2015;Schwedt and Dodick, 2009;Tedeschi et al, 2013), transcranial magnetic stimulation (Brighina et al, 2013;Brigo et al, 2013;Cosentino et al, 2014), transcranial direct current stimulation (Brighina et al, 2013;Cosentino et al, 2014), and electrophysiology (Ambrosini et al, 2003;de Tommaso et al, 2014;Magis et al, 2007Magis et al, , 2013. There is also evidence for altered visual perception in between migraine attacks that is consistent with changes to cortical function (Antal et al, 2005;Battista et al, 2010Battista et al, , 2011Ditchfield et al, 2006;McColl and Wilkinson, 2000;McKendrick et al, 2011;Shepherd, 2001Shepherd, , 2006Thabet et al, 2013;Wilkinson et al, 2008). We will not discuss this extensive literature base further in this review, which demonstrates clear cortical involvement in migraine both ictally and in between events.…”