Inhibition of return (IOR) refers to the fact that it takes longer for people to attend to recently examined locations than to novel locations. It has been argued that a single mechanism governs both IOR and negative priming (NP). If this is true, IOR and NP should share similar characteristics. Since NP depends on the use of repeated stimuli, in this study the dependence of IOR on repeated stimuli was explored. Experiments 1A-1D showed that, at longer cue-to-target-onset asynchrony (CTOA) intervals (613 and 906 msec), IOR could be observed only at repeatedly stimulated locations. However, IOR was observed when CTOA was short (253 msec) regardless of stimulus repetition. Experiments 2 and 3 replicated Experiments 1A-1D with a within-subjects design. The important role of memory representations in IOR is proposed.
To successfully and efficiently facilitate location of a target object in one's environment, one should utilize past experiences. This can be accomplished in multiple ways. One can learn the contingency between the target location and the search array (Chun & Jiang, 1998). When items to be searched are presented at two different times, one can purposely search through new items (Belopolsky, Theeuwes, & Kramer, 2005; Watson & Humphreys, 1997). The phenomenon of inhibition of return (IOR), which originally referred to a slower response to a recently attended location than to an uncued location, suggests that people can choose to search an item that has not been searched recently. Furthermore, people may achieve this by selectively inhibiting the previously searched items (Klein & Maclnnes, 1999; Posner & Cohen, 1984). In the present study, we investigated IOR to reveal how the inhibitory process influences behavior through the memory processes.
A cuing paradigm is generally used to study IOR. After the presence of an abrupt-onset cue, a target is presented either at the location previously occupied by the cue or at an uncued location. If the cue-to-target-onset asynchrony (CTOA) interval is short, a facilitatory effect is usually observed. Responses to targets at cued locations are faster than those to targets at uncued locations. If the CTOA interval is longer (e.g., more than 250 msec), responses to targets at cued locations are slower. It is hypothesized that attention is initially drawn to the cued location and then disengaged from that location, after which the previously searched location is inhibited, resulting in IOR (Posner & Cohen, 1984).
Inhibition has also been proposed as the mechanism of negative priming (NP; Tipper, 1985), which refers to a slowed response to previous distractors. Thus, it has been suggested that IOR and NP may share similar mechanisms (see, e.g., Buckolz, Boulougouris, O'Donnell, & Pratt, 2002; Christie & Klein, 2001 ; Houghton & Tipper, 1994). For example, Houghton and Tipper developed a computational model of inhibition that accounts for both IOR and NP. Also, response to a previous target location was found to be slow in an NP paradigm, showing an IOR-like effect with an NP procedure (see, e.g., Christie & Klein, 2001).
If the same inhibitory mechanism underlies both the IOR and NP, these two effects should follow the same operating principle. NP is usually contingent on stimulus repetition. The studies of Strayer, Grison, and colleagues (Orison & Strayer, 2001; Malley & Strayer, 1995; Strayer & Grison, 1999) demonstrated the dependence of identity NP on the use of repeated identities. Chao and Yeh (2005) showed that location NP in a naming task was dependent on the use of repeated locations. Both identity NP and location NP could be observed only when the stimuli had been used many times in the experiment. According to Strayer, Grison, and their colleagues, the use of repeated stimuli is critical to NP because only high-activation distractors are subject to inhibition. Moreover, it was found that the use of repeated stimuli as probe distractors could increase interference in the probe trial, which was important for the observation of NP in a naming task (Chao, Yeh, & Yang, 2003). …