Shape specific inhibition of return

Inhibition of the return (IOR) of attention is thought to facilitate visual search by encouraging the movement of attention to new locations or objects. Previous work has shown that IOR associated with realistic objects can be retrieved from memory after long intervals and intervening events. Furthermore, object-based IOR was shown to be mediated by object identity, as IOR does not spread to semantically related items (Morgan, Paul, & Tipper, 2005 Morgan, H. M., Paul, M. A. and Tipper, S. P. 2005. Inhibition of return can be associated with object identity but not with object category. European Journal of Cognitive Psychology, 17(4): 499–520. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]). The current experiments examined whether IOR can operate on the identity of briefly presented meaningless shapes. Attention was twice oriented to the left or right by the presentation of a red cue shape, then a green target shape requiring a rapid localisation response appeared on the left or right. The results revealed that IOR over short intervals was greater when the cue and target shapes were identical than when they were different, showing that IOR can be associated with the identity of meaningless shapes. However, no long-term IOR was observed for identical shapes, which suggests that long-term memory encoding and retrieval of IOR can only occur if the inhibition is associated with the identity of meaningful objects.