Long-term inhibition of return for spatial locations: evidence for a memory retrieval account

It has generally been accepted that attention is inhibited from returning to previously attended locations, and that this inhibition of return (IOR) lasts just two or three seconds. Recently, Tipper, Grison, and Kessler (2003) showed that IOR can occur over much longer periods of time provided the inhibition is encoded with a context-rich event. Here we examine standard (i.e., typical time range) and long-term IOR within the same experimental paradigm as a means to compare their properties. Experiment 1 used the simple displays typical of cueing paradigms and revealed that both standard and long-term IOR can be obtained under such conditions. Experiment 2 showed that both standard and long-term IOR occurred when there was incongruence between the required response on the current trial and that stored in memory. Furthermore, IOR was not produced when there was incongruence between a target feature (colour) of the current trial and that stored in memory. These results are consistent with a memory retrieval account of IOR and suggest that the same inhibitory mechanism may underlie both standard and long-term IOR.