Nawrot Elizabeth, Nawrot Mark
Department of Psychology, Minnesota State University Moorhead, Moorhead, MN, USA.
Center for Visual and Cognitive Neuroscience, Department of Psychology, North Dakota State University, Fargo, ND, USA.
J Vis. 2019 Nov 1;19(13):6. doi: 10.1167/19.13.6.
Research finds a relationship between the development of depth perception and ocular motion functions including smooth pursuit and ocular following response. Infants' reactions to looming stimuli also suggest sensitivity to optic flow information that specifies relative distance. With radial optic flow, an expanding flow field elicits involuntary convergent eye movements while a contracting one elicits involuntary divergent eye movements. This response suggests the visual system is interpreting the radial flow as a change in relative depth. We measured the oculomotor response to radial optic flow in infants aged two to five months. The stimulus comprised a radial optic flow pattern that expanded or contracted across eight 400 ms trials while eye position was monitored with a Tobii X120 eye tracker. A subset of infants also viewed trials of a static version of the stimulus. On average, most infants in each age group demonstrated convergence to the expanding pattern and divergence to the contracting one. Moreover, the difference in gain between the convergence and divergence eye movements was significant. The presence of correct-direction vergence eye movements in response to expansion and contraction provides further evidence that infants are sensitive to information that specifies relative motion in depth.
研究发现深度感知的发展与包括平稳跟踪和眼球跟随反应在内的眼球运动功能之间存在关联。婴儿对逼近刺激的反应也表明其对指定相对距离的光流信息敏感。对于放射状光流，扩展的流场会引发非自主的眼球内聚运动，而收缩的流场则会引发非自主的眼球散开运动。这种反应表明视觉系统将放射状流视为相对深度的变化。我们测量了2至5个月大婴儿对放射状光流的眼动反应。刺激包括一个放射状光流模式，该模式在八个400毫秒的试验中扩展或收缩，同时使用Tobii X120眼动仪监测眼睛位置。一部分婴儿还观看了该刺激的静态版本的试验。平均而言，每个年龄组的大多数婴儿对扩展模式表现出内聚，对收缩模式表现出散开。此外，内聚和散开眼球运动之间的增益差异显著。对扩展和收缩做出的正确方向的辐辏眼球运动的存在进一步证明婴儿对指定深度相对运动的信息敏感。
