Nyffeler Thomas, Rivaud-Pechoux Sophie, Pierrot-Deseilligny Charles, Diallo Ramata, Gaymard Bertrand
National Institute of Health and Medical Research, Pitie-Salpetriere Hospital, Paris, France.
Neuroreport. 2007 Jun 11;18(9):917-20. doi: 10.1097/WNR.0b013e32811d6cf5.
In the antisaccade task, a saccade must be triggered towards the mirror location of a visual target. The neural basis required for this visual vector inversion remains unclear, although neuronal activities reflecting this process have been recorded in the monkey lateral intraparietal area. We examined a patient with a small, right-sided, posterior parietal stroke who complained of difficulty in manipulating visual information. Antisaccades were markedly hypometric rightwards but normal leftwards. Largely unaffected performances in other saccade tasks revealed that visual and motor processing were not significantly affected. Antisaccade inaccuracy could therefore be ascribed to the impairment of visual vector inversion, a processing specifically required in this task. These findings provide the first evidence in humans that visual vector inversion could be an intrinsic property of the posterior parietal cortex.
在反扫视任务中，必须触发一个扫视运动，使其朝向视觉目标的镜像位置。尽管在猴子的外侧顶内区已经记录到了反映这一过程的神经元活动，但这种视觉矢量反转所需的神经基础仍不清楚。我们检查了一名患有右侧顶叶后部小面积中风的患者，该患者抱怨在处理视觉信息方面存在困难。反扫视运动明显向右幅度不足，但向左正常。在其他扫视任务中基本未受影响的表现表明，视觉和运动处理没有受到显著影响。因此，反扫视运动的不准确可能归因于视觉矢量反转的受损，这是该任务中特别需要的一种处理过程。这些发现为人类提供了首个证据，即视觉矢量反转可能是顶叶后部皮质的一种内在属性。
