Pierrot-Deseilligny C, Rivaud S, Gaymard B, Agid Y
Service de Neurologie, Hôpital de la Salpêtrière, Paris, France.
Brain. 1991 Jun;114 ( Pt 3):1473-85. doi: 10.1093/brain/114.3.1473.
Reflexive visually-guided saccade triggering may be facilitated or inhibited by the cerebral cortex. To study this control, saccades made towards suddenly appearing visual targets (saccade task) or away from them (antisaccade task) were recorded electro-oculographically in 45 patients with limited unilateral cerebral infarction. Lesions affected (1) the superior part of the angular gyrus (area 39 of Brodmann) in the posterior parietal cortex (PPC), (2) the dorsolateral prefrontal cortex (PFC) (area 46 of Brodmann), (3) the frontal eye field (FEF), or (4) the supplementary motor area (SMA). As these 4 types of lesions were located either in the right or the left cerebral hemisphere, patients were divided into 8 groups. Saccade latency, in the saccade task, and the percentage of errors (misdirected saccades made towards the visual target), in the antisaccade task, were compared in each group of patients with the values of 20 control subjects. In the saccade task, saccade latency was significantly increased bilaterally in the right PPC group. In the left PPC group, the increase in latency was less marked, and significant only for saccades made contralaterally to the lesion. In the different frontal groups, latency was unchanged or only slightly increased. These results confirm that the main area facilitating the triggering of reflexive visually-guided saccades is located in the PPC, in or near the superior part of the angular gyrus. The difference between right and left parietal lesions could be due to the predominance of the right hemisphere in the control of these saccades. In the antisaccade task, the percentage of errors was significantly increased bilaterally in both PFC groups compared with the control group and also to the FEF and SMA groups. These results suggest that the PFC is the main area in the cerebral hemisphere inhibiting reflexive visually-guided saccades.
大脑皮层可能会促进或抑制反射性视觉引导扫视的触发。为了研究这种控制机制，对45例单侧局限性脑梗死患者进行了眼电图记录，记录他们对突然出现的视觉目标做出的扫视（扫视任务）或背离目标的扫视（反扫视任务）。病变影响了：（1）顶叶后皮质（PPC）角回的上部（Brodmann 39区）；（2）背外侧前额叶皮质（PFC）（Brodmann 46区）；（3）额叶眼区（FEF）；或（4）辅助运动区（SMA）。由于这4种类型的病变位于右侧或左侧大脑半球，患者被分为8组。将每组患者在扫视任务中的扫视潜伏期以及在反扫视任务中的错误百分比（朝着视觉目标做出的错误导向扫视）与20名对照受试者的值进行比较。在扫视任务中，右侧PPC组双侧的扫视潜伏期显著增加。在左侧PPC组中，潜伏期的增加不太明显，仅对与病变对侧做出的扫视有显著影响。在不同的额叶组中，潜伏期未改变或仅略有增加。这些结果证实，促进反射性视觉引导扫视触发的主要区域位于PPC中，在角回上部或其附近。右侧和左侧顶叶病变之间的差异可能是由于右半球在控制这些扫视方面占主导地位。在反扫视任务中，与对照组相比，两个PFC组的错误百分比均显著增加，与FEF组和SMA组相比也是如此。这些结果表明，PFC是大脑半球中抑制反射性视觉引导扫视的主要区域。
