A study from Fang Fang’s group challenges the dominant view that the allocation of bottom-up attention (i.e., saliency map) is generated in the fronto-parietal attentional network. The bottom-up contribution to the allocation of exogenous attention is a saliency map, whose neural substrate is hard to identify because of possible contamination by top-down signals. They obviated this possibility using invisible stimuli to subjects to separate bottom-up attention from top-down attention and found that the bottom-up saliency map is created in V1.

Zhang X., Zhaoping L., Zhou T. and Fang F. (2012) Neural activities in V1 create a bottom-up saliency map.  Neuron  73:183-192