Jastorff Jan, Orban Guy A
Laboratorium voor Neuro- en Psychophysiologie, Katholieke Universiteit Leuven Medical School, B-3000 Leuven, Belgium.
J Neurosci. 2009 Jun 3;29(22):7315-29. doi: 10.1523/JNEUROSCI.4870-08.2009.
In a series of human functional magnetic resonance imaging experiments, we systematically manipulated point-light stimuli to identify the contributions of the various areas implicated in biological motion processing (for review, see Giese and Poggio, 2003). The first experiment consisted of a 2 x 2 factorial design with global shape and kinematics as factors. In two additional experiments, we investigated the contributions of local opponent motion, the complexity of the portrayed movement and a one-back task to the activation pattern. Experiment 1 revealed a clear separation between shape and motion processing, resulting in two branches of activation. A ventral region, extending from the lateral occipital sulcus to the posterior inferior temporal gyrus, showed a main effect of shape and its extension into the fusiform gyrus also an interaction. The dorsal region, including the posterior inferior temporal sulcus and the posterior superior temporal sulcus (pSTS), showed a main effect of kinematics together with an interaction. Region of interest analysis identified these interaction sites as the extrastriate and fusiform body areas (EBA and FBA). The local opponent motion cue yielded only little activation, limited to the ventral region (experiment 3). Our results suggest that the EBA and the FBA correspond to the initial stages in visual action analysis, in which the performed action is linked to the body of the actor. Moreover, experiment 2 indicates that the body areas are activated automatically even in the absence of a task, whereas other cortical areas like pSTS or frontal regions depend on the complexity of movements or task instructions for their activation.
在一系列人类功能磁共振成像实验中，我们系统地操控点光刺激，以确定参与生物运动处理的各个区域的作用（综述见Giese和Poggio，2003年）。第一个实验采用2×2析因设计，将全局形状和运动学作为因素。在另外两个实验中，我们研究了局部对抗运动、所描绘运动的复杂性以及一个回溯任务对激活模式的作用。实验1揭示了形状处理和运动处理之间的明显分离，产生了两个激活分支。一个腹侧区域，从枕外侧沟延伸至颞下回后部，显示出形状的主要效应，其延伸至梭状回也存在交互作用。背侧区域，包括颞下沟后部和颞上沟后部（pSTS），显示出运动学的主要效应以及交互作用。感兴趣区域分析将这些交互作用部位确定为纹外和梭状身体区域（EBA和FBA）。局部对抗运动线索仅产生少量激活，局限于腹侧区域（实验3）。我们的结果表明，EBA和FBA对应于视觉动作分析的初始阶段，其中所执行的动作与动作执行者的身体相关联。此外，实验2表明，即使在没有任务的情况下，身体区域也会自动激活，而其他皮层区域，如pSTS或额叶区域，其激活取决于运动的复杂性或任务指令。
