Journal article

Functional size of human visual area V1: A neural correlate of top-down attention

Ashika Verghese, Scott C Kolbe, Andrew J Anderson, Gary F Egan, Trichur R Vidyasagar



Heavy demands are placed on the brain's attentional capacity when selecting a target item in a cluttered visual scene, or when reading. It is widely accepted that such attentional selection is mediated by top-down signals from higher cortical areas to early visual areas such as the primary visual cortex (V1). Further, it has also been reported that there is considerable variation in the surface area of V1. This variation may impact on either the number or specificity of attentional feedback signals and, thereby, the efficiency of attentional mechanisms. In this study, we investigated whether individual differences between humans performing attention-demanding tasks can be related to the func..

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Funding Acknowledgements

This work was supported by an International Postgraduate Research Scholarship (Commonwealth Government of Australia), The Albert Shimmins Postgraduate Writing-Up Award (University of Melbourne) and a Science Faculty Scholarship (Department of Optometry and Vision Sciences, The University of Melbourne) to A.V. as well as by a seed grant from the Monash Biomedical Imaging Facility to G.E. and by the National Health and Medical Research Council grants to T.R.V. We thank the radiographer, Richard McIntyre and Dr. Neil Killeen for assistance with fMRI data collection.