记忆引导的双眼凝视转移过程中的视差-速度相互作用。

Department of Neuroscience, Erasmus University Medical Center, Rotterdam, The Netherlands.

Invest Ophthalmol Vis Sci. 2013 Mar 5;54(3):1656-64. doi: 10.1167/iovs.12-10680.

PURPOSE

Visual orientation toward remembered or visible visual targets requires binocular gaze shifts that are accurate in direction (version) and ocular distance (vergence). We determined the accuracy of combined version and vergence movements and the contribution of the abducting and adducting eye during gaze shifts toward memorized and visual targets in three-dimensional space.

METHODS

Subjects fixated either a "far" (94 cm) or "near" (31 cm) fixation light-emitting diode (LED) placed in front of the left eye. Next, in the memory-guided experiment, a target LED was lit for 80 ms (13 cm to the left or right and at 45 cm viewing distance). Subjects were instructed to make a saccade to the (remembered) target LED location. In the visually guided experiment, the target LED remained illuminated during the task. In both conditions, gaze shifts consisted of version and vergence movements.

RESULTS

Visually guided gaze shifts had both a fast intrasaccadic and a slow postsaccadic vergence component and were most accurate. During memory-guided gaze shifts, the abducting eye was more accurate than the adducting eye. Distance correction was achieved by slow postsaccadic vergence of the adducting eye. Memory-guided gaze shifts that required convergence lacked an intrasaccadic vergence component and were less accurate compared to memory-guided gaze shifts that required divergence.

CONCLUSIONS

Visually guided binocular gaze shifts are faster and more accurate than memory-guided binocular gaze shifts. During memory-guided gaze shifts, the abducting eye has a leading role, and an intrasaccadic vergence enhancement during convergence is reduced.

目的

对记忆中或可见的视觉目标进行视觉定向需要双眼注视的方向（偏差）和眼距（聚散）的准确变化。我们确定了在三维空间中，注视记忆中和视觉目标时，偏差和聚散眼球运动的综合准确性，以及外展和内收眼球在眼球运动中的作用。

方法

被试者注视左眼前方的“远”（94 厘米）或“近”（31 厘米）固定发光二极管（LED）。接下来，在记忆引导实验中，一个目标 LED 会点亮 80 毫秒（在左边 13 厘米或右边 45 厘米的视距处）。被试者被要求将视线转移到（记忆中的）目标 LED 位置。在视觉引导实验中，目标 LED 在任务过程中保持点亮。在这两种情况下，注视转移都包括偏差和聚散运动。