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首页> 外文期刊>Journal of Neurophysiology >Supplementary eye field: representation of saccades and relationship between neural response fields and elicited eye movements.
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Supplementary eye field: representation of saccades and relationship between neural response fields and elicited eye movements.

机译：补充眼场：扫视的表示以及神经反应场与引起的眼球运动之间的关系。

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The functional organization of the low-threshold supplementary eye field (SEF) was studied by analyzing presaccadic activity, electrically elicited saccades, and the relationship between them. Response-field optimal vectors, defined as the visual field coordinates or saccadic eye-movement dimensions evoking the highest neural discharge, were quantitatively estimated for 160 SEF neurons by systematically varying peripheral target location relative to a central fixation point and then fitting the responses to Gaussian functions. Saccades were electrically elicited at 109 SEF sites by microstimulation (70 ms, 10-100 microA) during central fixation. The distribution of response fields and elicited saccades indicated a complete representation of all contralateral saccades in SEF. Elicited saccade polar directions ranged between 97 and 262 degrees (data from left hemispheres were transformed to a right-hemisphere convention), and amplitudes ranged between 1.8 and 26.9 degrees. Response-field optimal vectors (right hemisphere transformed) were nearly all contralateral as well; the directions of 115/119 visual response fields and 80/84 movement response fields ranged between 90 and 279 degrees, and response-field eccentricities ranged between 5 and 50 degrees. Response-field directions for the visual and movement activity of visuomovement neurons were strongly correlated (r = 0.95). When neural activity and elicited saccades obtained at exactly the same sites were compared, response fields were highly predictive of elicited saccade dimensions. Response-field direction was highly correlated with the direction of saccades elicited at the recording site (r = 0.92, n = 77). Similarly, response-field eccentricity predicted the size of subsequent electrically elicited saccades (r = 0.49, n = 60). However, elicited saccades were generally smaller than response-field eccentricities and consistently more horizontal when response fields were nearly vertical. The polar direction of response fields and elicited saccades remained constant perpendicular to the cortical surface, indicating a columnar organization of saccade direction. Saccade direction progressively shifted across SEF; however, these orderly shifts were more indicative of a hypercolumnar organization rather than a single global topography. No systematic organization for saccade amplitude was evident. We conclude that saccades are represented in SEF by congruent visual receptive fields, presaccadic movement fields, and efferent mappings. Thus SEF specifies saccade vectors as bursts of activity by local groups of neurons with appropriate projections to downstream oculomotor structures. In this respect, SEF is organized like the superior colliculus and the frontal eye field even though SEF lacks an overall global saccade topography. We contend that all specialized oculomotor functions of SEF must operate within the context of this fundamental organization.
机译：通过分析眼前活动，电诱发的扫视及其之间的关系，研究了低阈值补充视场（SEF）的功能组织。通过系统地改变相对于中心固定点的外围目标位置，然后将响应拟合为高斯，对160个SEF神经元进行定量估计，将响应场最佳向量定义为引起最高神经放电的视野坐标或眼球的眼跳运动尺寸。功能。在中央固定期间，通过微刺激（70 ms，10-100 microA）在109 SEF位置电诱发扫视。响应场和引发的扫视的分布表明SEF中所有对侧扫视的完整表示。抬高的扫视极坐标方向介于97度和262度之间（来自左半球的数据转换为右半球常规），振幅范围介于1.8度和26.9度之间。响应场的最佳向量（右半球变换）几乎也都是对侧的。 115/119视觉响应场和80/84运动响应场的方向范围在90到279度之间，响应场偏心率的范围在5到50度之间。视觉运动神经元的视觉和运动活动的反应场方向密切相关（r = 0.95）。当比较在完全相同的位置获得的神经活动和诱发的扫视时，反应场高度预测了诱发的扫视范围。响应场方向与在记录位置引发的扫视方向高度相关（r = 0.92，n = 77）。类似地，响应场偏心率预测了后续电激发扫视的大小（r = 0.49，n = 60）。但是，引起的扫视通常小于响应场的离心率，并且当响应场接近垂直时，激发的扫视场始终更水平。响应场和引起的扫视的极向垂直于皮质表面保持恒定，表明扫视方向的柱状组织。扫视方向在SEF上逐渐转移;但是，这些有序的变化更表明了超柱状组织的存在，而不是单一的全球地形。没有系统的扫视振幅的组织是明显的。我们得出的结论是，扫视在SEF中由一致的视觉感受场，眼前运动场和传出的映射表示。因此，SEF将扫视向量指定为神经元局部组的活动爆发，并具有对下游动眼动结构的适当投影。在这方面，尽管SEF缺乏整体的全球扫视地形，但它的组织就像上丘和额眼。我们认为SEF的所有特殊动眼功能必须在这个基本组织的背景下运行。

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