Coste Clio P, Kleinschmidt Andreas
Department of Clinical Neurosciences, University Hospital of Geneva (HUG), Geneva, Switzerland; Department of Clinical Neurosciences, University of Geneva (UNIGE), CH-1211, Geneva, Switzerland; Unité 992, Cognitive Neuroimaging, Institut National de la Santé et de la Recherche Médicale, F-91191 Gif-sur-Yvette, France; NeuroSpin, Institut d'Imagerie Biomédicale/Direction des Sciences du Vivant/Commissariat à L'Énergie Atomique, F-91191 Gif-sur-Yvette, France.
Department of Clinical Neurosciences, University Hospital of Geneva (HUG), Geneva, Switzerland; Department of Clinical Neurosciences, University of Geneva (UNIGE), CH-1211, Geneva, Switzerland; Unité 992, Cognitive Neuroimaging, Institut National de la Santé et de la Recherche Médicale, F-91191 Gif-sur-Yvette, France; NeuroSpin, Institut d'Imagerie Biomédicale/Direction des Sciences du Vivant/Commissariat à L'Énergie Atomique, F-91191 Gif-sur-Yvette, France.
Neuroimage. 2016 Mar;128:264-272. doi: 10.1016/j.neuroimage.2016.01.026. Epub 2016 Jan 19.
Previous investigations of alertness have confounded it with selective attention because targets were highly predictable. To truly isolate alertness we devised a sparse event-related design with many different randomly appearing and interleaved auditory and visual targets, thereby rendering prediction inefficient. Using functional magnetic resonance imaging, we then analyzed the influence of local brain activity variations prior to task appearance on reaction times, thus avoiding signal contributions from stimulus-driven attention. Higher pre-stimulus activity in a cingulo-opercular network, and the default mode network, resulted in faster response speed but only the former network showed task-positive responses. Conversely, dorsal attention network pre-stimulus activity was overall irrelevant and on auditory trials even detrimental to performance. Thus, in a paradigm where no information predicted timing, modality or properties of a subsequent stimulus, our results dissociate alertness, both anatomically and functionally, from attention and establish the central role of the cingulo-opercular network for sustaining alertness.
先前对警觉性的研究将其与选择性注意混为一谈，因为目标具有高度可预测性。为了真正分离出警觉性，我们设计了一种稀疏的事件相关设计，其中有许多不同的随机出现且交错的听觉和视觉目标，从而使预测变得低效。然后，我们使用功能磁共振成像分析任务出现前局部脑活动变化对反应时间的影响，从而避免刺激驱动的注意产生的信号干扰。扣带-脑岛网络和默认模式网络中刺激前的活动较高，导致反应速度更快，但只有前一个网络显示出任务积极反应。相反，背侧注意网络的刺激前活动总体上无关紧要，在听觉试验中甚至对表现有害。因此，在一个没有信息预测后续刺激的时间、模态或属性的范式中，我们的结果在解剖学和功能上将警觉性与注意区分开来，并确立了扣带-脑岛网络在维持警觉性方面的核心作用。
