Öztürk Oya, Gündüz Ayşegül, E Kızıltan Meral
Department of Neurology, Bakirkoy Prof. Dr. Mazhar Osman Training and Research Hospital, İstanbul, Turkey.
Department of Neurology, Istanbul University, Cerrahpasa Medical Faculty, Istanbul, Turkey.
Neurosci Lett. 2018 Jun 11;677:84-87. doi: 10.1016/j.neulet.2018.04.047. Epub 2018 Apr 25.
In healthy subjects, magnitude of hand-evoked blink reflex (BR) is increased if the stimulated hand is positioned in the peripersonal space. Here, we aimed to investigate the modulation of hand-evoked BR in peripersonal space to understand alterations of cortical modulations of subcortical structures in cervical dystonia.
We recruited 23 patients with idiopathic cervical dystonia and 21 healthy subjects, all of whom had hand-evoked BR. The reflex was recorded while stimulated hand was close to face ('peripersonal space) and far away from face (extrapersonal space). Comparisons were done between two conditions in each group.
In extrapersonal space, magnitude of the reflex was bigger in patients compared to healthy subjects. In peripersonal space, magnitude of the reflex was increased in healthy subjects whereas it was reduced in patients. Comparisons of patients with and without sensory trick disclosed reflex magnitude was reduced in peripersonal space in patients with sensory trick whereas it did not change between two conditions in patients without sensory trick.
Enhancement of hand-evoked BR is a normal phenomenon that provides evidence for top-down modulation of its neural circuitry. In cervical dystonia, the normal modulation is lost which suggests abnormal modulatory effect of higher-order centers upon brainstem circuits. The pattern of alteration also differs if there is no sensory trick.
在健康受试者中，如果受刺激的手位于个人空间周围，手部诱发的眨眼反射（BR）幅度会增加。在此，我们旨在研究个人空间周围手部诱发BR的调制情况，以了解颈部肌张力障碍中皮质对皮质下结构调制的改变。
我们招募了23例特发性颈部肌张力障碍患者和21名健康受试者，他们均有手部诱发的BR。在受刺激的手靠近面部（“个人空间周围”）和远离面部（个人空间外）时记录反射。对每组的两种情况进行比较。
在个人空间外，患者的反射幅度比健康受试者大。在个人空间周围，健康受试者的反射幅度增加，而患者的反射幅度减小。对有和没有感觉技巧的患者进行比较发现，有感觉技巧的患者在个人空间周围反射幅度减小，而没有感觉技巧的患者在两种情况下反射幅度没有变化。
手部诱发BR的增强是一种正常现象，为其神经回路的自上而下调制提供了证据。在颈部肌张力障碍中，正常调制丧失，这表明高阶中枢对脑干回路有异常调制作用。如果没有感觉技巧，改变模式也会不同。
