Bayer Manuel, Zimmermann Eckart
Department of Experimental Psychology, Heinrich-Heine-University Düsseldorf, Düsseldorf 40225, Germany.
R Soc Open Sci. 2024 Aug 7;11(8):231545. doi: 10.1098/rsos.231545. eCollection 2024 Aug.
Keeping visual space constant across movements of the eye and head is a not yet fully understood feature of perception. To understand the mechanisms that update the internal coordinates of space, research has mostly focused on eye movements. However, in natural vision, head movements are an integral part of gaze shifts that enlarge the field of vision. Here, we directly compared spatial updating for eye and head movements. In a virtual reality environment, participants had to localize the position of a stimulus across the execution of a gaze shift. We found that performing head movements increased the accuracy of spatial localization. By manipulating the speed of the visual scene displacement that a head movement produced, we found that spatial updating takes into account the sensorimotor contingencies of vision. When we presented gaze-contingent visual motion, subjects overestimated the position of stimuli presented across gaze shifts. The overestimation decreased if subjects were allowed to perform eye movements during the head movement. We conclude that head movements contribute to stabilizing visual space across gaze shifts and that contingencies of head movements, rather than being cancelled, facilitate the updating.
在眼睛和头部运动过程中保持视觉空间恒定是一种尚未被完全理解的感知特征。为了理解更新空间内部坐标的机制，研究主要集中在眼球运动上。然而，在自然视觉中，头部运动是扩大视野的注视转移的一个组成部分。在这里，我们直接比较了眼球和头部运动的空间更新。在虚拟现实环境中，参与者必须在执行注视转移的过程中定位刺激物的位置。我们发现，进行头部运动会提高空间定位的准确性。通过操纵头部运动产生的视觉场景位移的速度，我们发现空间更新考虑了视觉的感觉运动偶联。当我们呈现与注视相关的视觉运动时，受试者高估了在注视转移过程中呈现的刺激物的位置。如果受试者在头部运动期间被允许进行眼球运动，这种高估就会降低。我们得出结论，头部运动有助于在注视转移过程中稳定视觉空间，并且头部运动的偶联不是被抵消，而是促进了更新。
