Hodgson Tim, Chamberlain Marcia, Parris Benjamin, James Martin, Gutowski Nicholas, Husain Masud, Kennard Christopher
Exeter Centre for Cognitive Neuroscience, School of Psychology, University of Exeter, Washington Singer Laboratories, Prince of Wales Road, Exeter EX4 4QG.
Brain. 2007 Jun;130(Pt 6):1525-37. doi: 10.1093/brain/awm064. Epub 2007 Apr 23.
It has been proposed that the inferior/ventrolateral frontal cortex plays a critical role in the inhibitory control of action during cognitive tasks. However, the contribution of this region to the control of eye movements has not been clearly established. Here, we describe the performance of a group of 23 frontal lobe damaged patients in an oculomotor rule switching task for which the association between a centrally presented visual cue and the direction of a saccade could change from trial to trial. A subset of 16 patients also completed the standard antisaccade task. Ventrolateral damage was found to be a significant predictor of errors in both tasks. Analysis of the rate at which patients corrected errors in the rule switching task also revealed an important dissociation between left and right hemisphere damaged patients. Whilst patients with left ventrolateral damage usually corrected response errors with secondary saccades, those with right hemisphere lesions often failed to do so. The results suggest that the inferior frontal cortex forms part of a wider frontal network mediating inhibitory control over stimulus elicited eye movements. The critical role played by the right ventrolateral region in cognitive tasks may arise due to an additional functional specialization for the monitoring and updating of task rules.
有人提出，额下回/腹外侧额叶皮层在认知任务期间对动作的抑制控制中起关键作用。然而，该区域对眼球运动控制的贡献尚未明确确立。在此，我们描述了一组23名额叶受损患者在一项动眼神经规则切换任务中的表现，在该任务中，中央呈现的视觉线索与扫视方向之间的关联可能在每次试验中发生变化。16名患者的一个子集还完成了标准的反扫视任务。发现腹外侧损伤是两项任务中错误的重要预测指标。对患者在规则切换任务中纠正错误的速率的分析还揭示了左半球和右半球受损患者之间的重要差异。虽然左腹外侧损伤的患者通常通过二次扫视纠正反应错误，但右半球病变的患者往往做不到。结果表明，额下回形成了一个更广泛的额叶网络的一部分，该网络介导对刺激引发的眼球运动的抑制控制。右腹外侧区域在认知任务中所起的关键作用可能是由于对任务规则的监测和更新的额外功能特化。
