On the relationship between occipital cortex activity and inhibition of return.

The present study explored the relationship between inhibition of return (IOR) and visual processes by seeking evidence that IOR and changes in event-related potential (ERP) indices of occipital cortex activity covary in response to experimental manipulation The presence or absence of a central reorienting event was manipulated within the context of a cue target experiment. When a reorienting event was presented in the interval between cue and target, IOR was accompanied by reductions in the amplitudes of early occipital ERP peaks oil validly cited trials relative to invalidly cued trials When a reorienting event was not presented, neither IOR nor modulations of the occipital ERP peaks was observed. These results provide strong evidence that IOR arises from changes in occipital visual processing We propose that IOR arises from a slowing of response-selection processes on validly cited trials due differences in the perceptual input to the decision-making process