FINAL ACCEPTED VERSION Title Cortico-cortical interactions in spatial attention: A combined ERP/TMS study Running head Cortico-cortical interactions in visual search Authors

To gain insight into the neural basis of visual attention we combined transcranial magnetic stimulation (TMS) and event related potentials (ERP) during a visual search task. Single-pulse TMS over right posterior parietal cortex (rPPC) delayed response times to targets during conjunction search, and this behavioural effect had a direct ERP correlate. The early phase of the N2pc component that reflects the focusing of attention onto target locations in a search display was eliminated over the right hemisphere when TMS was applied there, but was present when TMS was delivered to a control site (vertex). This finding demonstrates that rPPC TMS interferes with attentional selectivity in remote visual areas.