Cohen B S, Provasi J, Leboucher P, Israël I
Service ORL, Hôpital Saint-Antoine-UPMC, 46 Bld Raspail, 75007, Paris, France.
Laboratoire CHArt, EPHE-PSL, 4-14 rue Ferrus, 75014, Paris, France.
Exp Brain Res. 2017 Jul;235(7):2181-2188. doi: 10.1007/s00221-017-4959-7. Epub 2017 Apr 22.
The aim of this study was to establish the effect of vestibular lesion on vestibular imagery. Subjects were required to estimate verbally their passively travelled rotation angles in complete darkness, i.e., to activate vestibular imagery. During motion, the vestibulo-ocular reflex (VOR) was measured. Thus, we examined the coherence between the vestibulo-ocular reflex and self-rotation imagery, with vestibular-lesioned patients and healthy participants. Unilateral acute and chronic patients, bilateral patients, and healthy subjects were compared. The stimulus was a sequence of eight successive passive rotations, with four amplitudes (from 90° to 360°) in two directions. The VOR gain was lower in patients with unilateral lesions, for ipsilateral rotations. The healthy subjects had the highest gain and the bilateral group the lowest, on both rotation sides. Thanks to vestibular compensation after acute unilateral neuritis, the VOR gain increased in lesion side and decreased in healthy side, resulting in a similar gain in both sides. A deficit of vestibular imagery was found exclusively in patients with bilateral hyporeflexia, on both sides. The performance in vestibular imagery was good in the control group and correct in the unilateral patients. Finally, we found a significant correlation between the efficiency of the VOR and that of vestibular imagery, exclusively in the bilateral patients. The present study shows the complex relationship between vestibular imagery and the VOR. This imagery test contributes to another assessment of the spatial handicap of vestibular patients. It seems particularly interesting for patients with bilateral canal paresis and could be used to confirm this diagnosis.
本研究的目的是确定前庭损伤对前庭意象的影响。受试者被要求在完全黑暗中口头估计其被动旋转的角度，即激活前庭意象。在运动过程中，测量前庭眼反射（VOR）。因此，我们研究了前庭眼反射与自我旋转意象之间的相关性，研究对象包括前庭损伤患者和健康参与者。对单侧急性和慢性患者、双侧患者以及健康受试者进行了比较。刺激是一系列连续八次的被动旋转，在两个方向上有四个幅度（从90°到360°）。对于同侧旋转，单侧损伤患者的VOR增益较低。在两侧旋转时，健康受试者的增益最高，双侧组的增益最低。由于急性单侧神经炎后的前庭代偿，损伤侧的VOR增益增加，健康侧的VOR增益降低，导致两侧增益相似。仅在双侧反射减退的患者两侧发现前庭意象缺陷。前庭意象测试在对照组中表现良好，在单侧患者中结果正确。最后，我们发现仅在双侧患者中，VOR的效率与前庭意象的效率之间存在显著相关性。本研究显示了前庭意象与VOR之间的复杂关系。这种意象测试有助于对前庭患者的空间障碍进行另一项评估。对于双侧半规管麻痹患者来说似乎特别有意义，可用于确诊。
