Specificity of saccadic adaptation in three-dimensional space
Specificity of saccadic adaptation in three-dimensional space
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DOI：
10.1016/s0042-6989(96)00266-0
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发表时间：
1997-05-01
期刊：
影响因子：
1.8
通讯作者：
vanGisbergen, JAM
中科院分区：
文献类型：
--
作者：
Chaturvedi, V;vanGisbergen, JAM
已知扫视系统表现出相当程度的短期可塑性。早期的研究表明，扫视适应，而不是一个全球性的过程，影响所有扫视平等，有一定程度的空间分辨率。它的局部化性质已经从额面中的研究中变得明显，额面中的研究已经表明，沿沿着给定子午线诱导的短期扫视适应仅转移到有限范围的相邻方向。考虑到大多数自然的视线转移也有一个深度分量，我们调查是否可以推广到三维（3-D）space.Binocular眼球运动的眼跳自适应系统的方向特异性，而他们在水平面的视刺激眼跳记录在7名受试者。实验开始于记录基线扫视，所有从相同的注视点开始到更远的目标（远扫视）或同样偏心的更近的目标（近扫视）。接下来，通过在交替的远和近试验中在相反的方向上移位目标内扫视，我们试图同时减少远扫视的增益，同时增加近扫视的增益。这些实验，旨在引出一个状态的差分增益，专门设计，以适应只有扫视响应，因为目标是沿着沿着相应的等聚散度圆移位。为了研究径向差异的影响，在额状面上对沿着两条不同经线的扫视进行了类似的差分增益自适应实验，结果表明，当扫视系统受到压力时，它能够同时对不同深度平面的同向扫视采用不同的增益。类似地，在额状平面中也可以实现相反的增益自适应，但仅当径向扫视方向被充分分离时。短期扫视适应可以被示出为在两个垂直平面中具有方向特异性的事实表明，适应过程被限制在有限体积的3-D眼视空间。(C)1997年爱思唯尔科学有限公司
The saccadic system is known to exhibit a considerable degree of short-term plasticity. Earlier studies have shown that saccadic adaptation, rather than being a global process affecting all saccades equally, has a certain degree of spatial resolution. Its localized nature has become apparent from studies in the frontal plane which have shown that short-term saccadic adaptation, induced along a given meridian, transfers to only a limited range of neighbouring directions. Considering that most natural gaze shifts also have a depth component, we investigated whether the directional specificity of the saccadic adaptive system can be generalized to three-dimensional (3-D) space.Binocular eye movements were recorded in seven subjects while they made saccades to visual stimuli in the horizontal plane of regard. Experiments began by recording baseline saccades, all starting from the same fixation point to either a farther target (far saccades) or an equally eccentric nearer target (near saccades), Next, by displacing the target intra-saccadically in opposite directions in alternating far and near trials, we attempted to simultaneously reduce the gain of the far saccades while increasing the gain of the near saccades. These experiments, aimed at eliciting a state of differential gain, were specifically designed to adapt only the saccadic response, since targets were shifted along corresponding iso-vergence circles. To investigate the effect of varying the radial direction difference, similar differential gain adaptation experiments were conducted in the frontal plane for saccades along two different meridians.Our results show that when the saccadic system is pressured, it is capable of adopting different gains simultaneously for equal-direction saccades to different depth planes. Similarly, opposite gain adaptation can also be achieved in the frontal plane, but only if radial saccade directions are sufficiently separated. The fact that short-term saccadic adaptation can be shown to be directionally specific in two perpendicular planes suggests that the adaptation process is restricted to a limited volume of 3-D oculomotor space. (C) 1997 Elsevier Science Ltd.