Abstract
During visual search, inhibition of the return (IOR) of attention to previously examined items gives attention a momentum towards searching novel information, thus ensuring that the target will be detected. The inhibitory processes underlying IOR have been shown to be associated with both objects and locations. Research using face stimuli has shown that object-based inhibition can be retrieved from memory after relatively long periods (Tipper et al., 2003). However, it is possible that these long-term IOR effects were due to a perceptual mismatch between the cue signal and the target signal. The present study aims to confirm the existence of long-term IOR for faces, and also attempts to demonstrate long-term IOR using objects. In addition, this study examines whether these long-term IOR effects are caused by the retrieval of mismatching stimulus features. Presentation of two faces on the left and right alternated with presentation of two objects above and below fixation, and participants had to ignore a cue signal and make a localisation response to a target signal presented over one of the items. In the mismatch condition the cue signal was red and the target signal was green, whereas in the match condition the cue and target signals were identical. Long-term IOR for faces was observed when the cue and target were separated by 4.8 minutes and 64 displays. This IOR effect remained even when the cue and target signals were the same colour, which shows that the effect cannot be due to retrieval of mismatching stimulus features. Long-term IOR effects for objects were also unaffected by perceptual mismatch, however these IOR effects were less robust and only reached significance in the error analysis. These results suggest that inhibition associated with a cued item can be encoded into memory, such that later retrieval of the cued item reinstates inhibitory processing and encourages examination of new information.
This research was supported by a BBSRC studentship