Frens M A, Van Opstal A J, Van der Willigen R F
Department of Medical Physics and Biophysics, University of Nijmegen, The Netherlands.
Percept Psychophys. 1995 Aug;57(6):802-16. doi: 10.3758/bf03206796.
In this paper, we show that human saccadic eye movements toward a visual target are generated with a reduced latency when this target is spatially and temporally aligned with an irrelevant auditory nontarget. This effect gradually disappears if the temporal and/or spatial alignment of the visual and auditory stimuli are changed. When subjects are able to accurately localize the auditory stimulus in two dimensions, the spatial dependence of the reduction in latency depends on the actual radial distance between the auditory and the visual stimulus. If, however, only the azimuth of the sound source can be determined by the subjects, the horizontal target separation determines the strength of the interaction. Neither saccade accuracy nor saccade kinematics were affected in these paradigms. We propose that, in addition to an aspecific warning signal, the reduction of saccadic latency is due to interactions that take place at a multimodal stage of saccade programming, where the perceived positions of visual and auditory stimuli are represented in a common frame of reference. This hypothesis is in agreement with our finding that the saccades often are initially directed to the average position of the visual and the auditory target, provided that their spatial separation is not too large. Striking similarities with electrophysiological findings on multisensory interactions in the deep layers of the midbrain superior colliculus are discussed.
在本文中，我们表明，当视觉目标在空间和时间上与无关的听觉非目标对齐时，人类向该视觉目标的扫视眼动潜伏期会缩短。如果视觉和听觉刺激的时间和/或空间对齐发生变化，这种效应会逐渐消失。当受试者能够在二维空间中准确地定位听觉刺激时，潜伏期缩短的空间依赖性取决于听觉刺激与视觉刺激之间的实际径向距离。然而，如果受试者只能确定声源的方位角，那么水平目标间距决定了相互作用的强度。在这些范式中，扫视准确性和扫视运动学均未受到影响。我们提出，除了一种非特异性的警告信号外，扫视潜伏期的缩短是由于在扫视编程的多模态阶段发生的相互作用所致，在该阶段，视觉和听觉刺激的感知位置在一个共同的参照系中得到表征。这一假设与我们的发现一致，即只要视觉和听觉目标的空间间距不太大，扫视通常最初会指向它们的平均位置。文中还讨论了与中脑上丘深层多感官相互作用的电生理研究结果的显著相似之处。
