Effect of eye position within the orbit on electrically elicited saccadic eye movements: a comparison of the macaque monkey's frontal and supplementary eye fields.
Effect of eye position within the orbit on electrically elicited saccadic eye movements: a comparison of the macaque monkey's frontal and supplementary eye fields.
复制标题
眼眶内眼睛位置对电诱发眼球扫视运动的影响：猕猴额叶和辅助眼野的比较。
DOI：
10.1152/jn.1993.69.3.800
复制
发表时间：
1993
影响因子：
2.5
通讯作者：
Bruce,CJ
中科院分区：
文献类型：
--
作者：
Russo,GS;Bruce,CJ
1.我们定量地比较了眼位在眼眶内的扫视眼运动电引起的猕猴的额叶皮层的两个眼区：额叶眼场（FEF）和补充眼场（SEF）的影响。2.眼睛位置对电诱发扫视的影响是通过在猴子注视一个光点的同时提供70 ms的皮层内微刺激来研究的。位于矩形阵列上的不同注视点的测试被随机混合。在两只猴子的三个FEF中的38个位点和同一两只猴子的三个SEF中的59个位点上进行了完整的实验。阵列实验的刺激电流通常比位点阈值高10-20微安; FEF使用的平均电流为36微安，SEF使用的平均电流为49微安。3.通过计算当施加刺激时眼球在眼眶内的位置上的扫视眼球运动位移的线性回归，在每个部位量化初始眼球位置对引起的扫视的尺寸的影响的大小。该计算分别针对水平轴和垂直轴进行。我们把由此产生的一对回归系数称为“轨道摄动指数”。指数0.0表示不随不同的初始眼睛位置改变其轨迹的诱发扫视（恒定向量扫视），而指数-1.0表示在相同的轨道位置结束而不管初始眼睛位置的诱发扫视（目标定向扫视）。4.眼睛位置的影响在不同的网站。在FEF和SEF中，轨道扰动指数分布在大约0.0和-0.5之间，并且不同地点的水平和垂直指数高度相关。5.两个视野的平均轨道扰动指数都很小，没有显著差异。SEF和FEF的平均水平指数分别为-0.13和-0.16。平均垂直指数分别为-0.16和-0.13。SEF与FEF的差异均无统计学意义。6.在SEF和FEF中，产生较大幅度扫视的站点通常比产生较小扫视的站点具有更大的轨道效应。这一关系是造成空间电子辐射场和空间电子辐射场各站点轨道扰动指数变异性的主要原因。7.这些结果表明，SEF和FEF是没有区分彼此的轨道依赖性的电引起的眼跳。因此，他们没有证实先前假设的二分法，即FEF编码恒定矢量扫视和SEF编码目标定向扫视。（400字处截断摘要）
1. We quantitatively compared the effects of eye position within the orbit on saccadic eye movements electrically elicited from two oculomotor areas of the macaque monkey's frontal lobe cortex: the frontal eye field (FEF) and the supplementary eye field (SEF). 2. The effect of eye position on electrically elicited saccades was studied by delivering 70-ms trains of intracortical microstimulation while the monkeys fixated a spot of light. Tests of different fixation points located across a rectangular array were randomly intermixed. Complete experiments were carried out on 38 sites in three FEFs of two monkeys and 59 sites from three SEFs of the same two monkeys. Stimulation currents for the array experiments were usually 10–20 microA above the site threshold; the average current used was 36 microA for FEF and 49 microA for SEF. 3. The magnitude of effect of the initial eye position on the elicited saccade's dimensions was quantified at each site by computing the linear regression of saccadic eye movement displacement on the eye position within the orbit when stimulation was applied. This computation was done separately for the horizontal and vertical axes. We call the resulting pair of regression coefficients “orbital perturbation indexes.” Indexes of 0.0 represent elicited saccades that do not change their trajectory with different initial eye positions (constant-vector saccades), whereas indexes of -1.0 represent elicited saccades that end at the same orbital position regardless of initial eye position (goal-directed saccades). 4. The effect of eye position varied across sites. In both FEF and SEF, the orbital perturbation indexes were distributed between approximately 0.0 and -0.5, with the horizontal and vertical indexes highly correlated across sites. 5. The average orbital perturbation indexes were small for both eye fields and were not significantly different. The mean horizontal indexes were -0.13 and -0.16 for SEF and FEF, respectively. The mean vertical indexes were -0.16 and -0.13. Neither SEF versus FEF difference was statistically significant. 6. In both SEF and FEF, sites yielding larger-amplitude saccades generally had larger orbital effects than sites yielding smaller saccades. This relationship accounted for the majority of the variability of the orbital perturbation indexes across sites in both SEF and FEF. 7. These results indicate that SEF and FEF are not distinguished from each other by the orbital dependence of their electrically elicited saccades. Thus they do not confirm the previously hypothesized dichotomy that FEF codes constant-vector saccades and SEF codes goal-directed saccades.(ABSTRACT TRUNCATED AT 400 WORDS)