Cazzoli Dario, Kaufmann Brigitte C, Paladini Rebecca E, Müri René M, Nef Tobias, Nyffeler Thomas
Perception and Eye Movement Laboratory, Department of Biomedical Research (DBMR) and Department of Neurology, University of Bern, and Inselspital, Bern University Hospital, Bern, Switzerland.
ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland.
Brain Commun. 2020 Dec 26;3(1):fcaa220. doi: 10.1093/braincomms/fcaa220. eCollection 2021.
The clinical link between spatial and non-spatial attentional aspects in patients with hemispatial neglect is well known; in particular, an increase in alerting can transitorily help to allocate attention towards the contralesional side. In models of attention, this phenomenon is postulated to rely on an interaction between ventral and dorsal cortical networks, subtending non-spatial and spatial attentional aspects, respectively. However, the exact neural underpinnings of the interaction between these two networks are still poorly understood. In the present study, we included 80 right-hemispheric patients with subacute stroke (50% women; age range: 24-96), 33 with and 47 without neglect, as assessed by paper-pencil cancellation tests. The patients performed a computerized task in which they were asked to respond as quickly as possible by button-press to central targets, which were either preceded or not preceded by non-spatial, auditory warning tones. Reaction times in the two different conditions were measured. In neglect patients, a warning tone, enhancing activity within the ventral attentional 'alerting' network, could boost the reaction (in terms of shorter reaction times) of the dorsal attentional network to a visual stimulus up to the level of patients without neglect. Critically, using voxel-based lesion-symptom mapping analyses, we show that this effect significantly depends on the integrity of the right anterior insula and adjacent inferior frontal gyrus, i.e., right-hemispheric patients with lesions involving these areas were significantly less likely to show shorter reaction times when a warning tone was presented prior to visual target appearance. We propose that the right anterior insula and inferior frontal gyrus are a critical hub through which the ventral attentional network can 'alert' and increase the efficiency of the activity of the dorsal attentional network.
半侧空间忽视患者空间和非空间注意方面的临床联系是众所周知的；特别是，警觉性的提高可以暂时帮助将注意力分配到对侧。在注意模型中，这种现象被假定依赖于腹侧和背侧皮质网络之间的相互作用，分别支撑非空间和空间注意方面。然而，这两个网络之间相互作用的确切神经基础仍然知之甚少。在本研究中，我们纳入了80例右半球亚急性卒中患者（50%为女性；年龄范围：24-96岁），通过纸笔划消测试评估，其中33例有忽视，47例无忽视。患者执行一项计算机任务，要求他们通过按键对中央目标尽可能快地做出反应，中央目标之前有或没有非空间听觉警告音。测量了两种不同条件下的反应时间。在忽视患者中，一种增强腹侧注意“警觉”网络内活动的警告音，可以将背侧注意网络对视觉刺激的反应（以更短的反应时间衡量）提高到无忽视患者的水平。至关重要的是，使用基于体素的病变-症状映射分析，我们表明这种效应显著取决于右侧前岛叶和相邻的额下回的完整性，即，病变累及这些区域的右半球患者在视觉目标出现之前出现警告音时，显著不太可能表现出更短的反应时间。我们提出，右侧前岛叶和额下回是一个关键枢纽，腹侧注意网络可以通过该枢纽“警觉”并提高背侧注意网络活动的效率。
