Mechanisms underlying the (re)alignment of covert and overt visual attention

It is widely assumed that attention comprises overt and covert orienting mechanisms. Following a peripheral cue covert and overt attention can be decoupled. But how are they subsequently realigned? We examined whether realignment towards a fixated (central) location is determined solely by the time since cue onset, or whether it is also influenced by the spatial location of a subsequent reorienting cue. We used the spatial cueing paradigm to examine this in the context of inhibition of return (IOR) - i.e., slower target detection at previously cued locations. After an exogenous cue, a reorienting cue was shown at either central fixation or peripherally. IOR was greater following the central than the peripheral re-orienting cue. This indicates that the direction of realignment modulates inhibition of previously-cued locations. We propose that stronger inhibition arising from central reorienting cues reflects a fundamental bias to realign covert and overt attention at a central fixation.