Visuotopic cortical connectivity underlying attention revealed with white-matter tractography. J Neurosci 2012 Feb 22;32(8):2773-82
Date
02/24/2012Pubmed ID
22357860Pubmed Central ID
PMC3321828DOI
10.1523/JNEUROSCI.5419-11.2012Scopus ID
2-s2.0-84857352505 (requires institutional sign-in at Scopus site) 81 CitationsAbstract
Visual attention selects behaviorally relevant information for detailed processing by resolving competition for representation among stimuli in retinotopically organized visual cortex. The signals that control this attentional biasing are thought to arise in a frontoparietal network of several brain regions, including posterior parietal cortex. Recent studies have revealed a topographic organization in the intraparietal sulcus (IPS) that mirrors the retinotopic organization in visual cortex, suggesting that connectivity between these regions might provide the mechanism by which attention acts on early cortical representations. Using white-matter imaging and functional MRI, we examined the connectivity between two topographic regions of IPS and six retinotopically defined areas in visual cortex. We observed a strong positive correlation between attention modulations in visual cortex and connectivity of posterior IPS, suggesting that these white-matter connections mediate the attention signals that resolve competition among stimuli for representation in visual cortex. Furthermore, we found that connectivity between IPS and V1 consistently respects visuotopic boundaries, whereas connections to V2 and V3/VP disperse by 60%. This pattern is consistent with changes in receptive field size across regions and suggests that a primary role of posterior IPS is to code spatially specific visual information. In summary, we have identified white-matter pathways that are ideally suited to carry attentional biasing signals in visuotopic coordinates from parietal control regions to sensory regions in humans. These results provide critical evidence for the biased competition theory of attention and specify neurobiological constraints on the functional brain organization of visual attention.
Author List
Greenberg AS, Verstynen T, Chiu YC, Yantis S, Schneider W, Behrmann MAuthor
Adam S. Greenberg PhD Associate Dean, Associate Professor in the Biomedical Engineering department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AdultAnalysis of Variance
Attention
Brain Mapping
Female
Functional Laterality
Humans
Image Processing, Computer-Assisted
Magnetic Resonance Imaging
Male
Nerve Fibers, Myelinated
Oxygen
Photic Stimulation
Statistics as Topic
Visual Cortex
Visual Fields
Visual Pathways
Young Adult
