INITIAL DIRECTIONS AND LANDING POSITIONS OF BINOCULAR SACCADES
INITIAL DIRECTIONS AND LANDING POSITIONS OF BINOCULAR SACCADES
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DOI：
10.1016/0042-6989(95)00077-r
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发表时间：
1995-12-01
期刊：
影响因子：
1.8
通讯作者：
SLOOT, OB
中科院分区：
文献类型：
--
作者：
ERKELENS, CJ;SLOOT, OB
现有的用于产生扫视的模型预测扫视的起始位置和着陆位置之间的固定轨迹，实验数据表明扫视具有相当可变的轨迹。本研究的目的是量化双眼扫视轨迹的可变性，并测试在多大程度上可以通过向现有模型的分量添加噪声来描述空间可变性。我们研究了自定步调的扫视轨迹，在额状面的多个静止的视觉目标之间进行扫视，对每个目标进行超过75次扫视，用巩膜线圈技术测量双眼的水平和垂直运动。我们将每次主眼跳的起始位置到结束位置的方向定义为有效方向，将眼跳的起始位置到眼跳已覆盖2.5度距离时的眼位的方向定义为眼跳的初始方向，我们发现初始方向的变异性比有效方向大2 - 7倍，有效方向比初始方向更准确和更精确。对于每只眼睛，对特定目标进行的扫视的初始方向和有效方向是负相关的，尽管在大多数情况下相当弱（0.1 < r（2）< 0.5）。与此相反，初始方向总是高度相关的（r（2）> 0.8）的相关性的相关性，有效方向之间也发现了高度相关性，我们得出结论，扫视的曲线是一个有目的的控制策略的结果，扫视轨迹表明，最初，眼睛是大致在目标的方向加速，然后他们被引导到目标。可能的模型的分析表明，变异性主要进入扫视系统的神经元扫视生成的中央阶段，我们得出结论，从模拟，其中我们使用不同的模型的扫视生成，方向变异性的主要来源是反馈回路的一部分，这一结论提供了间接证据的反馈回路中的扫视系统的存在。
Existing model for the generation of saccades predict fixed trajectories between start and landing positions of saccades, Experimental data show that saccades have rather variable trajectories, The objective of the present research is to quantify the variability in trajectories of binocular saccades and to test in how far spatial variability can be described by adding noise to components of existing models, We studied the trajectories of self-paced saccades, Saccades were made between a number of stationary, visual targets lying in the frontal plane, More than 75 saccades were made to each target, Horizontal and vertical movements of both eyes were measured with a scleral coil technique. We defined the direction from starting position to end position of each primary saccade as the effective direction, We defined the direction from starting position to the eye position when the saccade had covered a distance of 2.5 deg as the initial direction of the saccade, We find that variability is two to seven times larger in initial directions than in effective directions, Effective directions are more accurate and more precise than initial directions, For each eye, initial and effective directions of saccades made to a particular target are negatively correlated, although in most cases rather weakly (0.1 < r(2) < 0.5). Contrastingly, initial directions are always highly correlated (r(2) > 0.8) of associated binocular saccades, High correlations are also found between effective directions, We conclude that curvedness of saccades is the result of a purposeful control strategy, The saccadic trajectories show that, initially, the eyes are accelerated roughly in the direction of the target and subsequently they are guided to the target. Analysis of possible models suggests that variability predominantly enters the saccadic system at a central stage of neuronal saccade generation, We conclude from simulations, in which we used different models of saccade generation, that the major sources of directional variability are part of a feedback loop, This conclusion provides indirect evidence for the presence of a feedback loop in the saccadic system.