Visual metacontrast masking in migraine

Abstract

The inhibitory processes involved in the masking tasks employed in this study do not appear to be impaired in migraine. Their better overall performance may reflect a sensitivity difference, perhaps as a consequence of a heightened neuronal response, which varies with the migraine cycle.

Global Shape Processing Deficits Are Amplified by Temporal Masking in Migraine

“…Moreover, masking of V1 processes (meta-contrast masking) results in migraineurs performing better than controls, 6,9 opposite to the effect described here. When target shapes are backward masked, migraineurs, especially MA, performed poorer than controls.…”

“…It has been shown recently that the better performance of migraineurs on a metacontrast masking task can be explained by a generally higher sensitivity compared to controls rather than a difference in masking. 9 Our results are consonant with the notion that inhibition generally is not reduced in migraine, at least for those neuronal pathways that are responsible for masking. 9,50 An alternative account for the differences between migraineurs and controls is neuronal noise.…”

“…9 Our results are consonant with the notion that inhibition generally is not reduced in migraine, at least for those neuronal pathways that are responsible for masking. 9,50 An alternative account for the differences between migraineurs and controls is neuronal noise. An increase in internal noise can explain why migraineurs perform poorer than controls in a range of tasks.…”

“…As has been pointed out recently, 9 care should be taken when considering differences between groups for backward masking conditions when these groups also behave differently in the absence of a mask. Accordingly, we normalized the data for the masked conditions (Fig.…”

“…6 Recently, Shepherd et al confirmed that migraineurs experienced less masking than controls. 9 However, migraineurs also discriminated between targets better when they were unmasked, implying that a heightened neuronal response in migraine may underlie their enhanced performance, rather than a specific deficit with inhibitory processes. Other measures of inhibitory control have found migraineurs to perform at a near-normal 10,11 or reduced level, 12,13 also inconsistent with the faulty inhibition model.…”