Effects of Supra- and Sub-liminal Emotional Cues on Inhibition of Return

Abstract

In the classical exogenous cue-target paradigm, when a target is presentedin the same location as a cue within a stimulus onset asynchrony(SOA) of 250 ms or less, target detection is facilitated. However,when the SOA is extended to more than 250 ms, target detection isslowed at the cued location. This phenomenon is called inhibitionof return (IOR). IOR is generally assumed to be an adaptive mechanismwhich enhances the chance of success or survival by maximizing thechance of detecting important information in visual search duringhuman evolution. If so, the time course and/or magnitude of IOR maybe affected by biological information of the cue. If a cue providesinformation relevant to individual's survival, then attention maynot be inhibited from reorienting to the cue. However, previous evidenceconcerning this issue is controversial. This study is to furtherexamine whether IOR is modulated by emotional valences of face, whichconvey important biological and social information. We hypothesizedthat emotional information conveyed through supraliminally presentedface cues may not differentially affect the IOR effect, because thisinformation could be suppressed by the top-down control settingsdemanding no interference from emotion, whereas emotional informationconveyed through subliminally presented face cues may affect patternof the IOR effect, because this information is processed automaticallyand it escapes from top-down suppression. A total of 32 undergraduatestudents participated in Experiments 1 and 2, which manipulated thenumber of simultaneously cued locations. Faces with different emotionalvalences (happy, angry and neutral) were as uninformative peripheralcues, supraliminally in Experiment 1 and subliminally in Experiment2, while the participants were instructed to make detection responsesto the target, which was presented at one of the cued locations orat an uncued location, as quickly and accurately as possible. Experiment1 obtained an overall IOR effect but the magnitude of this effectwas not affected by the emotional valences of face cues. Experiment2 obtained a significant IOR effect, but only for the neutral facecues. These findings are consistent with our hypothesis, suggestingthat IOR can be modulated by the property of biologically importantcues. The evolutionary significance of the IOR mechanism was discussed.(PsycINFO Database Record (c) 2010 APA, all rights reserved) (journalabstract)