Ontogenetic Development of Vestibulo-Ocular Reflexes in Amphibians.
Ontogenetic Development of Vestibulo-Ocular Reflexes in Amphibians.
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DOI：
10.3389/fncir.2016.00091
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发表时间：
2016
影响因子：
3.5
通讯作者：
Straka H
中科院分区：
文献类型：
--
作者：
Branoner F;Chagnaud BP;Straka H
前庭-眼反射(VOR)保证了运动和被动诱导头部/身体运动时的凝视稳定性。在像两栖动物这样的早熟脊椎动物中，前庭反射在运动活动开始时是非常早的。虽然内耳的形成和感觉-运动通路的组装在孵化后不久就基本完成，但角度和平移/倾斜VOR显示出不同的功能起点，并随着不同的时间进程而成熟。耳石衍生的眼球运动在孵化后立即出现，而半规管诱发的眼球运动的出现和渐进性改善是延迟的，并依赖于获得足够大的半规管直径。此外，半规管功能也是调节最初全方位耳石来源的VOR所必需的。调谐是由于加强了前庭-眼睛的连接，在自然的头/身体运动中，半规管和耳石输入共同激活了前庭-眼睛连接。这表明，分子机制最初指导着基本的个体发生连接，而半规管依赖的活动需要建立反射的时空特异性。虽然在被动的头部/身体运动中激活了强大的VOR，但运动传出副本为幼蛙和成年蛙基于尾巴和肢体的游泳过程中的代偿性眼球运动提供了主要来源。用于凝视稳定的主动/被动运动相关信号的整合发生在中央前庭神经元中，这些神经元沿着菱形核1-8以分段重复的功能群排列。然而，与大多数其他感觉系统的地形图不同，运动相关信号的感觉-运动转换发生在由眼外运动输出靶点定义的分段特定神经元组中。
Vestibulo-ocular reflexes (VOR) ensure gaze stability during locomotion and passively induced head/body movements. In precocial vertebrates such as amphibians, vestibular reflexes are required very early at the onset of locomotor activity. While the formation of inner ears and the assembly of sensory-motor pathways is largely completed soon after hatching, angular and translational/tilt VOR display differential functional onsets and mature with different time courses. Otolith-derived eye movements appear immediately after hatching, whereas the appearance and progressive amelioration of semicircular canal-evoked eye movements is delayed and dependent on the acquisition of sufficiently large semicircular canal diameters. Moreover, semicircular canal functionality is also required to tune the initially omnidirectional otolith-derived VOR. The tuning is due to a reinforcement of those vestibulo-ocular connections that are co-activated by semicircular canal and otolith inputs during natural head/body motion. This suggests that molecular mechanisms initially guide the basic ontogenetic wiring, whereas semicircular canal-dependent activity is required to establish the spatio-temporal specificity of the reflex. While a robust VOR is activated during passive head/body movements, locomotor efference copies provide the major source for compensatory eye movements during tail- and limb-based swimming of larval and adult frogs. The integration of active/passive motion-related signals for gaze stabilization occurs in central vestibular neurons that are arranged as segmentally iterated functional groups along rhombomere 1–8. However, at variance with the topographic maps of most other sensory systems, the sensory-motor transformation of motion-related signals occurs in segmentally specific neuronal groups defined by the extraocular motor output targets.
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影响因子：
2.7
作者：
Díaz, C;Puelles, L;Glover, JC
通讯作者：
Glover, JC
DOI：
10.1111/j.1749-6632.1999.tb09175.x
发表时间：
1999-01-01
期刊：
OTOLITH FUNCTION IN SPATIAL ORIENTATION AND MOVEMENT
影响因子：
--
作者：
Büttner-Ennever, JA
通讯作者：
Büttner-Ennever, JA
DOI：
10.1001/archneurpsyc.1933.02240140009001
发表时间：
1933-08-01
影响因子：
--
作者：
de Nó, RL
通讯作者：
de Nó, RL
影响因子：
2.5
作者：
Currie SP;Combes D;Scott NW;Simmers J;Sillar KT
通讯作者：
Sillar KT
影响因子：
2.9
作者：
Birinyi, A;Straka, H;Dieringer, N
通讯作者：
Dieringer, N