Top-down cortical interactions in visuospatial attention

• Published in: Brain Structure and Function Vol. 222; no. 7; pp. 3127 - 3145
• Main Authors: Meehan, Timothy P., Bressler, Steven L., Tang, Wei, Astafiev, Serguei V., Sylvester, Chad M., Shulman, Gordon L., Corbetta, Maurizio
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-09-2017; Springer Nature B.V
• Subjects: Acoustic Stimulation; Adult; Analysis of Variance; Attention - physiology; Attention task; Biomedical and Life Sciences; Biomedicine; Brain; Cell Biology; Eye; Female; Frontal Lobe - diagnostic imaging; Frontal Lobe - physiology; Functional Laterality; Hemispheric laterality; Humans; Image Processing, Computer-Assisted; Intraparietal sulcus; Magnetic Resonance Imaging; Male; Models, Neurological; Neurology; Neurosciences; Occipital lobe; Original Article; Oxygen - blood; Receptive field; Visual cortex; Visual Cortex - diagnostic imaging; Visual Cortex - physiology; Visual perception; Visual Perception - physiology; Hemispheric asymmetry; Dorsal attention network; Intrinsic connectivity; Cognitive control; Task set
• ISSN: 1863-2653; 1863-2661; 0340-2061
• DOI: 10.1007/s00429-017-1390-6

The voluntary allocation of visuospatial attention depends upon top-down influences from the frontal eye field (FEF) and intraparietal sulcus (IPS)—the core regions of the dorsal attention network (DAN)—to visual occipital cortex (VOC), and has been further associated with within-DAN influences, particularly from the FEF to IPS. However, the degree to which these influences manifest at rest and are then modulated during anticipatory visuospatial attention tasks remains poorly understood. Here, we measured both undirected and directed functional connectivity (UFC, DFC) between the FEF, IPS, and VOC at rest and during an anticipatory visuospatial attention task, using a slow event-related design. Whereas the comparison between rest and task indicated FC modulations that persisted throughout the task duration, the large number of task trials we collected further enabled us to measure shorter timescale modulations of FC across the trial. Relative to rest, task engagement induced enhancement of both top-down influences from the DAN to VOC, as well as bidirectional influences between the FEF and IPS. These results suggest that task performance induces enhanced interaction within the DAN and a greater top-down influence on VOC. While resting FC generally showed right hemisphere dominance, task-related enhancement favored the left hemisphere, effectively balancing a resting hemispheric asymmetry, particularly within the DAN. On a shorter (within-trial) timescale, VOC-to-DAN and bidirectional FEF-IPS influences were transiently elevated during the anticipatory period of the trial, evincing phasic modulations related to changing attentional demands. In contrast to these task-specific effects, resting and task-related influence patterns were highly correlated, suggesting a predisposing role for resting organization, which requires minimal tonic and phasic modulations for control of visuospatial attention.