Anagnostou Evangelos, Heimberger Joachim, Sklavos Sokratis, Anastasopoulos Dimitri
Department of Physiology, Dizziness and Balance Unit, School of Health Sciences, University of Athens, Greece.
Neuroreport. 2011 Mar 30;22(5):239-43. doi: 10.1097/WNR.0b013e3283451769.
Alexander's law states that the amplitude of the spontaneous nystagmus grows with increasing gaze in the direction of the fast phase. Using the search-coil method we employed head impulses at various eye-in-orbit azimuth angles to test (i) whether the normal vestibulo-ocular reflex (VOR) in the behaviorally relevant high-frequency range has intrinsic properties that could account for Alexander's law and (ii) whether such properties can also be shown in patients with unilateral vestibulopathy. We showed that the gain of the VOR remained unaffected by eye-in-orbit position in contols and in patients, both on ipsilesional and contralesional stimuli. These findings suggest that eye-in-orbit position does not directly modulate the activity in VOR pathways, neither during unbalanced but reciprocal (in controls), nor during unbalanced and nonreciprocal natural vestibular stimulation (in patients).
亚历山大定律指出，自发性眼球震颤的幅度会随着注视方向朝着快相方向增加而增大。我们使用搜索线圈法，在不同的眼眶内方位角施加头部脉冲，以测试（i）行为相关高频范围内的正常前庭眼反射（VOR）是否具有能够解释亚历山大定律的内在特性，以及（ii）这些特性是否也能在单侧前庭病变患者中表现出来。我们发现，无论是在对照组还是患者中，无论是同侧刺激还是对侧刺激，VOR的增益都不受眼眶内位置的影响。这些发现表明，眼眶内位置不会直接调节VOR通路的活动，无论是在不平衡但相互的（在对照组中），还是在不平衡且非相互的自然前庭刺激（在患者中）期间。
