Layher Georg, Neumann Heiko
Institute of Neural Information Processing, Ulm University, Ulm, Germany.
Front Psychol. 2018 Aug 28;9:1455. doi: 10.3389/fpsyg.2018.01455. eCollection 2018.
Human articulated motion can be readily recognized robustly even from impoverished so-called point-light displays. Such sequence information is processed by separate visual processing channels recruiting different stages at low and intermediate levels of the cortical visual processing hierarchy. The different contributions that motion and form information make to form articulated, or biological, motion perception are still under investigation. Here we investigate experimentally whether and how specific spatio-temporal features, such as extrema in the motion energy or maximum limb expansion, indicated by the lateral and longitudinal extension, constrain the formation of the representations of articulated body motion. In order to isolate the relevant stimulus properties we suggest a novel masking technique, which allows to selectively impair the ankle information of the body configuration while keeping the motion of the point-light locations intact. Our results provide evidence that maxima in feature channel representations, e.g., the lateral or longitudinal extension, define elemental features to specify key poses of biological motion patterns. These findings provide support for models which aim at automatically building visual representations for the cortical processing of articulated motion by identifying temporally localized events in a continuous input stream.
即使是从所谓的简化点光显示中，也能很容易地稳健识别出人体关节运动。这种序列信息由不同的视觉处理通道进行处理，这些通道在皮质视觉处理层次结构的低、中级水平上调用不同阶段。运动和形状信息对形成关节运动或生物运动感知的不同贡献仍在研究中。在这里，我们通过实验研究特定的时空特征，如运动能量的极值或最大肢体伸展（由横向和纵向伸展表示）是否以及如何约束关节身体运动表征的形成。为了分离相关的刺激属性，我们提出了一种新颖的掩蔽技术，该技术允许在保持点光位置运动完整的同时，选择性地损害身体构型的脚踝信息。我们的结果提供了证据，表明特征通道表征中的最大值，例如横向或纵向伸展，定义了基本特征以指定生物运动模式的关键姿势。这些发现为旨在通过识别连续输入流中时间上局部化的事件来自动构建用于关节运动皮质处理的视觉表征的模型提供了支持。
