Top-down cortical interactions in visuospatial attention.
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.
Center for Complex Systems and Brain Sciences, Florida Atlantic University, 777 Glades Road, Boca Raton, FL, 33431, USA.
Timothy P
TP
Meehan
Center for Complex Systems and Brain Sciences, Florida Atlantic University, 777 Glades Road, Boca Raton, FL, 33431, USA. bressler@fau.edu.|Department of Psychology, Florida Atlantic University, Boca Raton, FL, 33431, USA. bressler@fau.edu.
Steven L
SL
Bressler
Center for Complex Systems and Brain Sciences, Florida Atlantic University, 777 Glades Road, Boca Raton, FL, 33431, USA.
Wei
W
Tang
Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA.
Serguei V
SV
Astafiev
Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, 63110, USA.
Chad M
CM
Sylvester
Department of Neurology, Washington University School of Medicine, St. Louis, MO, 63110, USA.
Gordon L
GL
Shulman
Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA.|Department of Neurology, Washington University School of Medicine, St. Louis, MO, 63110, USA.|Department of Neurobiology, Washington University School of Medicine, St. Louis, MO, 63110, USA.
Maurizio
M
Corbetta
D000161:Acoustic Stimulation; D000328:Adult; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000000981:diagnostic imaging* / Q000502:physiology*; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008959:Models, Neurological; D010100:Oxygen / Q000097:blood; D014793:Visual Cortex / Q000000981:diagnostic imaging* / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*
D010100:Oxygen
Cognitive control; Dorsal attention network; Hemispheric asymmetry; Intrinsic connectivity; Task set