Billino Jutta, Braun Doris I, Böhm Klaus-Dieter, Bremmer Frank, Gegenfurtner Karl R
Justus-Liebig-Universität, Giessen, Germany.
Neuropsychologia. 2009 Aug;47(10):2133-44. doi: 10.1016/j.neuropsychologia.2009.04.005. Epub 2009 Apr 16.
Neuropsychological studies in humans provide evidence for a variety of extrastriate cortical areas involved in visual motion perception. Multiple mechanisms underlying processing of different motion types have been proposed, however, support for cortical specialization has remained controversial so far. We therefore studied motion perception in 23 patients with focal lesions to various cortical areas and considered translational motion, heading from radial flow, as well as biological motion. Patients' detection thresholds were compared with age-specific data from a large healthy control sample (n=122). Elevated thresholds and significant threshold asymmetries between both visual hemifields were defined as deficits. Contrary to prevalent opinion, we found a high prevalence of motion deficits in our sample. Impairment was restricted to a specific motion type in 10 patients, whereas only a single patient showed a deficit for multiple motion types. Functional areas were determined by lesion density plots and by comparison between patients with and without a specific deficit. Results emphasize a dissociation between basic motion processing and processing of complex motion. Anatomical analysis confirmed critical occipito-temporo-parietal areas for perception of translational motion. In contrast, heading perception from radial flow proved to be remarkably robust to most lesions. We exclusively identified the frontal eye fields as a critical structure. Biological motion perception relied on distinct pathways involving temporal, parietal, and frontal areas. Although precise functional roles of identified areas cannot be determined conclusively, results clearly indicate regional specialization for motion types of different complexity. We propose a network for motion processing involving widely distributed cortical areas.
针对人类的神经心理学研究为参与视觉运动感知的多个纹外皮层区域提供了证据。尽管已经提出了多种不同运动类型处理背后的机制，但到目前为止，对皮层特化的支持仍存在争议。因此，我们研究了23名患有不同皮层区域局灶性病变的患者的运动感知，并考虑了平移运动、基于放射状流的方向感知以及生物运动。将患者的检测阈值与来自大量健康对照样本（n = 122）的年龄特异性数据进行比较。将两个视觉半视野之间阈值升高和显著的阈值不对称定义为缺陷。与普遍观点相反，我们在样本中发现运动缺陷的发生率很高。10名患者的损伤仅限于特定的运动类型，而只有一名患者表现出多种运动类型的缺陷。通过病变密度图以及有和没有特定缺陷的患者之间的比较来确定功能区域。结果强调了基本运动处理和复杂运动处理之间的分离。解剖学分析证实了枕颞顶叶关键区域对平移运动的感知。相比之下，基于放射状流的方向感知对大多数病变具有显著的抗性。我们唯一确定额眼区为关键结构。生物运动感知依赖于涉及颞叶、顶叶和额叶区域的不同通路。尽管不能最终确定所确定区域的确切功能作用，但结果清楚地表明了不同复杂程度运动类型的区域特化。我们提出了一个涉及广泛分布的皮层区域的运动处理网络。
