Head unrestrained horizontal gaze shifts after unilateral labyrinthectomy in the rhesus monkey
Head unrestrained horizontal gaze shifts after unilateral labyrinthectomy in the rhesus monkey
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DOI：
10.1007/s002210100810
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发表时间：
2001-09-01
影响因子：
2
通讯作者：
Angelaki, DE
中科院分区：
文献类型：
--
作者：
Newlands, SD;Hesse, SV;Angelaki, DE
在眼头注视组合的定向扫视之后，正常猴子会表现出补偿性的眼睛反向旋转，以在头部继续运动时稳定注视。这种反向旋转的增益（眼速/头速）接近一致，是前庭眼反射 (VOR) 的表现。急性单侧迷路切除术 (UL) 在被动头部旋转期间导致 VOR 严重不对称，并且随着时间的推移无法完全恢复。本研究的目的是比较水平注视移动期间反向旋转增益的恢复情况与 UL 后被动 VOR 的恢复情况。在 UL 后的第一周，反向旋转增益是不对称的，头部向病变侧移动时较低，但头部向完整侧移动时几乎正常。虽然反向旋转增益的这种不对称性在 UL 后一周内得到解决，但被动 VOR 的不对称性仍然存在。在 UL 治疗后的第一周，行为表现普遍较差，目光转移不准确和延迟时间较长的发生率很高。此外，动物使用较慢的头部运动，使得 UL 后第一周的眼球扫视期间的峰值头部振幅明显低于对照值。双侧迷路切除术 (BL) 导致较大但对称的反向旋转缺陷，与被动 VOR 相反，随着时间的推移，其表现出显着的恢复。假设 UL 后反向旋转增益的恢复有多个来源的贡献，包括对侧完整的迷路和头部运动的输出副本。
Following the orienting saccade of a combined eye-head gaze shift, normal monkeys exhibit a compensatory eye counterrotation that stabilizes gaze as the head movement continues. This counterrotation, which has a gain (eye velocity/head velocity) of near unity, is a manifestation of the vestibule-ocular reflex (VOR). Acute unilateral labyrinthectomy (UL) causes severe asymmetry in the VOR during passive head rotations that recovers incompletely over time. The purpose of this investigation was to compare the recovery of the counterrotation gain during horizontal gaze shifts with that of the passive VOR after UL. During the 1st week after UL, counterrotation gains were asymmetric, being lower for head movements towards the lesion but nearly normal for head movements towards the intact side. Whereas this asymmetry in the counterrotation gain resolved within a week after UL, asymmetries in the passive VOR persisted. During the 1st week after UL, behavioral performance was generally poor, with a high incidence of inaccurate gaze shifts and larger latencies. In addition, animals used slower head movements such that peak head amplitude during the eye saccade was significantly lower during the 1st week after UL as compared to control values. Bilateral labyrinthectomy (BL) resulted in larger but symmetric deficits in counterrotation, which, contrary to the passive VOR, exhibited significant recovery over time. It is hypothesized that recovery of counterrotation gain after UL has contributions from multiple sources, including the contralateral intact labyrinth and an efference copy of the head movement.