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Visuospatial attention allows observers to focus awareness on one or several pieces of information in the visual world. Recent evidence suggests that a network of brain regions including superior frontal, inferior parietal, and superior temporal cortices is involved in the top-down control of visuospatial attention. The goal of this study was to determine whether this network mediates attentional control in different visual frames of reference (FORs), or whether partially separable neural systems underlie attentional orienting in each. Participants were cued to locations defined within viewer- or object-centered FORs and made form discriminations on targets subsequently presented at those locations. Cortical responses to attention-directing cues were recorded with event-related fMRI at 1.5T. Consistent with previous work, a number of brain regions were selectively activated by attention-directing cues including superior frontal, inferior parietal, and superior temporal cortices. Critically, this network was differentially engaged when attention was grounded in different FORs. Specifically, superior temporal regions were more active when spatial attention was deployed within an object-centered FOR, whereas superior frontal regions were more active when spatial attention was deployed within a viewer-centered FOR. Inferior parietal regions were equally responsive to attention-directing cues in both FORs. These results suggest that attentional orienting in different FORs is mediated by an overlapping network of brain regions, but that this network is differentially engaged when attention is deployed in different reference frames.

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