Antal A, Temme J, Nitsche M A, Varga E T, Lang N, Paulus W
Department of Clinical Neurophysiology, Georg-August University of Göttingen, Robert Koch Strasse 40, 37075 Göttingen, Germany.
Cephalalgia. 2005 Oct;25(10):788-94. doi: 10.1111/j.1468-2982.2005.00949.x.
Much research on visual functions in migraine has pinpointed the existence of abnormal visual processing between attacks. However, it is not clear if this is due to cortical hyper- or hypoexcitability. We aimed to clarify this issue by comparing motion perception thresholds of subjects with migraine with (MA) or without aura (MoA) and control subjects. Two types of dot kinetograms were used: in the first experiment coherently moving dots were presented in an incoherent environment, while in the second only coherent motion was seen. Subjects with migraine displayed significantly impaired motion perception compared with controls when they had to detect the direction of the coherently moving dots in an incoherent environment, while they were slightly better in a direction discrimination task, where only coherent motion was presented. This pattern of results is comparable to those achieved by an external excitability enhancement of V5 induced in healthy human subjects in a former study of our group. According to this, a cortical excitability enhancement can result in an impaired focusing on a given signal against a noisy background, but improves perception of non-ambiguous stimuli. Thus we conclude that migraineurs display enhanced visual cortical excitability between attacks in V5.
许多关于偏头痛视觉功能的研究都指出发作间期存在异常的视觉处理过程。然而，目前尚不清楚这是由于皮层兴奋性过高还是过低所致。我们旨在通过比较有先兆偏头痛（MA）或无先兆偏头痛（MoA）患者与对照受试者的运动感知阈值来阐明这一问题。使用了两种类型的点运动图：在第一个实验中，在不连贯的环境中呈现连贯移动的点，而在第二个实验中只看到连贯运动。当偏头痛患者必须在不连贯的环境中检测连贯移动点的方向时，与对照组相比，他们的运动感知明显受损，而在只呈现连贯运动的方向辨别任务中，他们的表现略好。这种结果模式与我们小组之前一项研究中在健康人类受试者中通过外部增强V5兴奋性所获得的结果相当。据此，皮层兴奋性增强会导致在嘈杂背景下对给定信号的聚焦受损，但会改善对明确刺激的感知。因此，我们得出结论，偏头痛患者在发作间期V5区的视觉皮层兴奋性增强。
