Deslauriers Johnathan, Ansado Jennyfer, Marrelec Guillaume, Provost Jean-Sébastien, Joanette Yves
Centre de Recherche, Institut Universitaire de Gériatrie de Montréal, Canada; Université de Montréal, Montreal, Quebec, Canada; Université du Québec en Outaouais, Gatineau, Quebec, Canada.
Université du Québec en Outaouais, Gatineau, Quebec, Canada.
Brain Res. 2017 Feb 15;1657:288-296. doi: 10.1016/j.brainres.2016.12.017. Epub 2016 Dec 21.
Multiple studies have found neurofunctional changes in normal aging in a context of selective attention. Furthermore, many articles report intrahemispheric alteration in functional networks. However, little is known about age-related changes within the Ventral Attention Network (VAN), which underlies selective attention. The aim of this study is to examine age-related changes within the VAN, focusing on connectivity between its regions. Here we report our findings on the analysis of 27 participants' (13 younger and 14 older healthy adults) BOLD signals as well as their performance on a letter-matching task. We identified the VAN independently for both groups using spatial independent component analysis. Three main findings emerged: First, younger adults were faster and more accurate on the task. Second, older adults had greater connectivity among posterior regions (right temporoparietal junction, right superior parietal lobule, right middle temporal gyrus and left cerebellum crus I) than younger adults but lower connectivity among anterior regions (right anterior insula, right medial superior frontal gyrus and right middle frontal gyrus). Older adults also had more connectivity between anterior and posterior regions than younger adults. Finally, correlations between connectivity and response time on the task showed a trend toward connectivity in posterior regions for the older group and in anterior regions for the younger group. Thus, this study shows that intrahemispheric neurofunctional changes in aging also affect the VAN. The results suggest that, in contexts of selective attention, posterior regions increased in importance for older adults, while anterior regions had reduced centrality.
多项研究发现，在选择性注意的背景下，正常衰老过程中存在神经功能变化。此外，许多文章报道了功能网络的半球内改变。然而，对于作为选择性注意基础的腹侧注意网络（VAN）内与年龄相关的变化，我们知之甚少。本研究的目的是检查VAN内与年龄相关的变化，重点关注其区域之间的连接性。在此，我们报告了对27名参与者（13名年轻和14名年长的健康成年人）的血氧水平依赖（BOLD）信号分析结果以及他们在字母匹配任务中的表现。我们使用空间独立成分分析分别为两组独立识别出VAN。出现了三个主要发现：第一，年轻成年人在任务中速度更快且更准确。第二，年长成年人后脑部区域（右侧颞顶交界区、右侧顶上小叶、右侧颞中回和左侧小脑蚓部I）之间的连接性比年轻成年人更强，但前脑部区域（右侧前岛叶、右侧额上回内侧和右侧额中回）之间的连接性比年轻成年人更低。年长成年人前后脑区域之间的连接性也比年轻成年人更多。最后，任务中连接性与反应时间之间的相关性显示，年长组在后部区域存在连接性趋势，而年轻组在前部区域存在连接性趋势。因此，本研究表明衰老过程中的半球内神经功能变化也会影响VAN。结果表明，在选择性注意的情况下，后部区域对年长成年人的重要性增加，而前部区域的中心性降低。
