Interaction between facilitation and inhibition of return facilitates visual search

It has been suggested (Pratt and Castel, 2001 Vision Research 41 3903 - 3908) that either inhibition of return (IOR) or facilitation of return (FOR) occurs in discrimination tasks, depending on some arbitrary combination of target features and task demands. Here we show that: (a) FOR always occurs to the non-responding feature or location; (b) FOR is always coupled to the responding feature whereas IOR is always coupled to the responding location; (c) there is an interaction between the effects associated with responding and non-responding features/locations (either FOR - FOR or IOR - FOR). Overall, these results support the distinction between two separate visual functions which interact resulting in an ecologically plausible heuristic that facilitates recently viewed features which have appeared in recently visited locations and inhibits recently visited locations that contain features recently associated with a distractor.