Institute of Ophthalmology, University College London, London, United Kingdom.
Invest Ophthalmol Vis Sci. 2014 Apr 17;55(4):2539-46. doi: 10.1167/iovs.14-13877.
People with migraine are relatively poor at judging the direction of motion of coherently moving signal dots when interspersed with noise dots drifting in random directions, a task known as motion coherence. Although this has been taken as evidence of impoverished global pooling of motion signals, it could also arise from unreliable coding of local direction (of each dot), or an inability to segment signal from noise (noise-exclusion). The aim of this study was to determine how these putative limits contribute to impoverished motion processing in migraine.
Twenty-two participants with migraine (mean age, 34.7 ± 8.3 years; 16 female) and 22 age- and sex-matched controls (mean age, 34.4 ± 6.2 years) performed a motion-coherence task and a motion-equivalent noise task, the latter quantifying local and global limits on motion processing. In addition, participants were tested on analogous equivalent noise paradigms involving judgments of orientation and size, so that the specificity of any findings (to visual dimension) could be ascertained.
Participants with migraine exhibited higher motion-coherence thresholds than controls (P = 0.01, independent t-test). However, this difference could not be attributed to deficits in either local or global processing since they performed normally on all equivalent noise tasks (P > 0.05, multivariate ANOVA).
These findings indicate that motion perception in the participants with migraine was limited by an inability to exclude visual noise. We suggest that this is a defining characteristic of visual dysfunction in migraine, a theory that has the potential to integrate a wide range of findings in the literature.
当与随机方向漂移的噪声点交织在一起时，偏头痛患者在判断连贯运动信号点的运动方向方面相对较差，这项任务被称为运动一致性。尽管这被认为是运动信号整体汇集受损的证据，但也可能是由于局部方向（每个点的方向）编码不可靠，或者无法将信号与噪声（噪声排除）分开。本研究的目的是确定这些假定的限制因素如何导致偏头痛患者运动处理能力受损。
22 名偏头痛患者（平均年龄 34.7 ± 8.3 岁；16 名女性）和 22 名年龄和性别匹配的对照者（平均年龄 34.4 ± 6.2 岁）完成了运动一致性任务和运动等效噪声任务，后者量化了运动处理的局部和整体限制。此外，还对参与者进行了类似的等效噪声范式测试，包括方向和大小的判断，以便确定任何发现的特异性（到视觉维度）。
偏头痛患者的运动一致性阈值高于对照组（P = 0.01，独立 t 检验）。然而，这种差异不能归因于局部或整体处理的缺陷，因为他们在所有等效噪声任务中表现正常（P > 0.05，多元方差分析）。
这些发现表明，偏头痛患者的运动感知受到无法排除视觉噪声的限制。我们认为，这是偏头痛视觉功能障碍的一个特征，这一理论有可能整合文献中的一系列发现。
