Albano J E
Center for Visual Science, University of Rochester, NY 14627, USA.
Vision Res. 1996 Jul;36(14):2087-98. doi: 10.1016/0042-6989(96)89627-1.
The saccadic system rapidly adjusts the amplitude of refixation movements to visual targets when abnormal postsaccadic errors occur. This is called rapid saccadic adaptation. It is not yet clear whether this form of adaptation produces changes related to oculocentric mechanisms, such as retinal error or motor error, or orbitocentric mechanisms, such as eye or gaze position. These experiments were designed to test whether rapid saccadic adaptation was orbitocentric, oculocentric, or both by creating a precise sensory motor mismatch between the visual target and the required saccade. Measurements were made to determine adaptive changes as function of (1) saccade direction; (2) eye position; and (3) saccade amplitude. Changes were found to be amplitude- and direction-specific but changes were generalized across a broad range of orbital positions. Two conditions of adaptation: increasing and decreasing amplitude, produced quantitatively similar results, indicating that similar mechanisms underlie both processes. Thus, these data support the view that changes during rapid saccadic adaptation are organized principally in a retina-referenced (oculocentric) map, but only broadly, if at all, in a head-referenced (orbitocentric) map. The changes are consistent with a mechanism represented in a spatial mapping of either retinal or motor error.
当出现异常的扫视后误差时，扫视系统会迅速调整对视觉目标的再注视运动幅度。这被称为快速扫视适应。目前尚不清楚这种适应形式是否会产生与眼心机制（如视网膜误差或运动误差）或眶心机制（如眼睛或注视位置）相关的变化。这些实验旨在通过在视觉目标和所需扫视之间制造精确的感觉运动不匹配，来测试快速扫视适应是眶心的、眼心的，还是两者皆有。进行测量以确定作为（1）扫视方向；（2）眼睛位置；和（3）扫视幅度的函数的适应性变化。发现变化是幅度和方向特异性的，但变化在广泛的眼眶位置上是普遍存在的。两种适应条件：增加和减小幅度，产生了定量相似的结果，表明这两个过程都有相似的机制。因此，这些数据支持这样一种观点，即快速扫视适应过程中的变化主要是在视网膜参考（眼心）地图中组织的，但在头部参考（眶心）地图中，如果有的话，也只是大致如此。这些变化与视网膜或运动误差的空间映射中所代表的机制是一致的。
