Department of Ultrastructural Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan; Ichinohe Neural System Group, Laboratory for Molecular Analysis of Higher Brain Functions, RIKEN Brain Science Institute, RIKEN, Wako, Saitama, Japan.
Department of Ultrastructural Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan; Ichinohe Neural System Group, Laboratory for Molecular Analysis of Higher Brain Functions, RIKEN Brain Science Institute, RIKEN, Wako, Saitama, Japan.
J Neurosci Methods. 2017 Nov 1;291:51-60. doi: 10.1016/j.jneumeth.2017.08.006. Epub 2017 Aug 9.
The visual system in primates can be segregated into motion and shape pathways. Interaction occurs at multiple stages along these pathways. Processing of shape-from-motion and biological motion is considered to be a higher-order integration process involving motion and shape information. However, relatively limited types of stimuli have been used in previous studies on these integration processes.
We propose a new algorithm to extract object motion information from natural movies and to move random dots in accordance with the information. The object motion information is extracted by estimating the dynamics of local normal vectors of the image intensity projected onto the x-y plane of the movie.
An electrophysiological experiment on two adult common marmoset monkeys (Callithrix jacchus) showed that the natural and random dot movies generated with this new algorithm yielded comparable neural responses in the middle temporal visual area.
In principle, this algorithm provided random dot motion stimuli containing shape information for arbitrary natural movies. This new method is expected to expand the neurophysiological and psychophysical experimental protocols to elucidate the integration processing of motion and shape information in biological systems.
The novel algorithm proposed here was effective in extracting object motion information from natural movies and provided new motion stimuli to investigate higher-order motion information processing.
灵长类动物的视觉系统可以分为运动和形状通路。这些通路在多个阶段都存在相互作用。对运动形状和生物运动的处理被认为是一个涉及运动和形状信息的更高阶整合过程。然而，在之前关于这些整合过程的研究中，相对有限的刺激类型被使用。
我们提出了一种新的算法，从自然电影中提取物体运动信息，并根据信息移动随机点。物体运动信息是通过估计投影到电影 x-y 平面上的图像强度的局部法向量的动力学来提取的。
对两只成年普通狨猴（Callithrix jacchus）的电生理实验表明，用这种新算法生成的自然和随机点电影在中颞视觉区产生了类似的神经反应。
原则上，这种算法为任意自然电影提供了包含形状信息的随机点运动刺激。这种新方法有望扩展神经生理和心理物理实验方案，以阐明生物系统中运动和形状信息的整合处理。
这里提出的新算法有效地从自然电影中提取物体运动信息，并提供了新的运动刺激来研究更高阶的运动信息处理。
