Experimental Psychology, Helmholtz Institute, Utrecht University, Heidelberglaan 2, 3584 CS Utrecht, The Netherlands.
Exp Brain Res. 2012 Sep;221(4):377-84. doi: 10.1007/s00221-012-3178-5. Epub 2012 Jul 22.
The decision about which location should be the goal of the next eye movement is known to be determined by the interaction between auditory and visual input. This interaction can be explained by the vector theory that states that each element (either visual or auditory) in a scene evokes a vector in the oculomotor system. These vectors determine the direction in which the eye movement is initiated. Because auditory input is lateralized and localizable in most studies, it is currently unclear how non-lateralized auditory input interacts with the vectors evoked by visual input. In the current study, we investigated the influence of a non-lateralized auditory non-target on saccade accuracy (saccade angle deviation from the target) and latency in a single-target condition in Experiment 1 and a double-target condition in Experiment 2. The visual targets in Experiment 2 were positioned in such a way that saccades on average landed in between the two targets (i.e., a global effect). There was no effect of the auditory input on saccade accuracy in the single-target condition, but auditory input did influence saccade accuracy in the double-target condition. In both experiments, saccade latency increased when auditory input accompanied the visual target(s). Together, these findings show that non-lateralized auditory input enhances all vectors evoked by visual input. The results will be discussed in terms of their possible neural substrates.
下一个眼球运动的目标位置的决定被认为是由听觉和视觉输入之间的相互作用决定的。这种相互作用可以用向量理论来解释，该理论指出场景中的每个元素（视觉或听觉）都会在眼球运动系统中引发一个向量。这些向量决定了眼球运动的起始方向。由于听觉输入在大多数研究中是侧向化和可定位的，目前尚不清楚非侧向化的听觉输入如何与视觉输入引发的向量相互作用。在当前的研究中，我们在实验 1 的单目标条件和实验 2 的双目标条件下，研究了非侧向化的非目标听觉输入对眼球运动准确性（眼球运动角度与目标的偏差）和潜伏期的影响。实验 2 中的视觉目标的位置使得眼球运动平均落在两个目标之间（即全局效应）。在单目标条件下，听觉输入对眼球运动准确性没有影响，但在双目标条件下，听觉输入确实影响了眼球运动准确性。在这两个实验中，当听觉输入伴随着视觉目标时，眼球运动潜伏期会增加。总之，这些发现表明，非侧向化的听觉输入增强了视觉输入引发的所有向量。将根据其可能的神经基础讨论这些结果。
