Neuroscience Department, Laboratory for Behavioral Neurology and Imaging of Cognition, University of Geneva, Geneva, Switzerland.
Neuroscience Department, Laboratory for Behavioral Neurology and Imaging of Cognition, University of Geneva, Geneva, Switzerland; Neurology Department, University Hospital of Geneva, Geneva, Switzerland; Laboratory of Cognitive Neurorehabilitation, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
Cortex. 2019 Nov;120:223-239. doi: 10.1016/j.cortex.2019.06.009. Epub 2019 Jun 29.
Posterior thalamic pulvinar nuclei have been implicated in different aspects of spatial attention, but their exact role in humans remain unclear. Most neuropsychological studies of attention deficits after pulvinar lesion have concerned single patients or small samples. Here we examined a group of 13 patients with focal damage to posterior thalamus on a visual search task with faces, allowing us to test several hypotheses concerning pulvinar function in controlling attention to visually salient or emotionally significant stimuli. Our results identified two subgroups of thalamic patients with distinct patterns of attentional responsiveness to emotional and colour features in face targets. One group with lesions located in anterior and ventral portions of thalamus showed intact performance, with a normal facilitation of visual search for faces with emotional (fearful or happy) expressions on both side of space, similar to healthy controls. By contrast, a second group showed a slower and poorer detection of face targets, most severe for neutral faces, but with a paradoxically enhanced facilitation by both colour and emotional features. This second group had lesions centred on the pulvinar, involving mainly the dorso-medial sectors in patients showing enhanced effects of colour features, but extending to more dorso-lateral sectors in those with enhanced effects of emotional features. These findings reveal that pulvinar nuclei are not critical for orienting attention to emotionally or visually salient features, but instead provide new evidence in support of previous hypotheses suggesting an important role in controlling attention in visual scenes with distracting information.
丘脑后核的被盖部在空间注意的不同方面都有牵连，但它们在人类中的具体作用仍不清楚。大多数关于丘脑被盖部损伤后注意力缺陷的神经心理学研究都涉及单个患者或小样本。在这里，我们在一项面孔视觉搜索任务中检查了 13 名患有后丘脑局灶性损伤的患者，这使我们能够测试关于控制对视觉显著或情感重要刺激的注意力的几个假设。我们的结果确定了两组具有不同注意力反应模式的丘脑患者，分别对应于面孔目标中的情感和颜色特征。一组患者的损伤位于丘脑的前侧和腹侧，表现出正常的视觉搜索功能，对空间两侧具有情感（恐惧或快乐）表情的面孔有正常的促进作用，与健康对照组相似。相比之下，第二组患者对面孔目标的检测速度较慢且较差，对中性面孔的检测最差，但颜色和情感特征都有异常增强的促进作用。第二组患者的损伤集中在被盖部，主要涉及到表现出色域特征增强效应的背内侧区域，但在那些具有增强的情感特征效应的患者中，损伤扩展到更背外侧的区域。这些发现表明，丘脑后核对于定向注意到情感或视觉显著特征并不是至关重要的，而是为先前的假设提供了新的证据，这些假设表明它们在控制有分心信息的视觉场景中的注意力方面起着重要作用。
