title: Cingulo-opercular network activity maintains alertness.
abstract: 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.
authors.affiliation: 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. Electronic address: clio.coste@gmail.com.
authors.forename: Clio P
authors.initials: CP
authors.lastname: Coste
authors.affiliation: 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.
authors.forename: Andreas
authors.initials: A
authors.lastname: Kleinschmidt
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009434:Neural Pathways / Q000502:physiology
keywords: Attention; Human brain; Spontaneous activity; Vigilance; fMRI