Effect of Different Directions of Attentional Shift on Inhibition of Return in Three-dimensional Space

摘要

When attention is oriented to a peripheral cue, there is facilitation of processing of nearby stimuli. The brief period of facilitation is followed by a long-lasting inhibitory effect in which there is delayed responding to stimuli presented at subsequently cued location. Although it has been documented that the mechanisms underlying the earlier facilitatory effect of attentional orienting in three-dimensional space (3D) (Chen et at., 2012), it remains poorly understood how visuospatial attention is shifted in depth at the later inhibitory phase. In the present study, by incorporating the Posner exogenous cueing paradigm into a virtual 3D environment, we aimed at investigating the influence of different direction of attentional shift along the depth dimension on inhibition of return (IOR). We presented targets either close to or far from the participants and manipulated the validity of cues to construct different direction of attentional shift [targets appeared in the same as location of the cues, Within_Valid (WV); targets appeared in the depth plane that the cues located to, but in the opposite hemispace, Within_Invalid (WIV); targets appeared in the uncued depth plane, but at the same hemispace of the cue, Between_Invalid_Same_Hemispace (BIV_SH); targets appeared not only in the uncued depth plane, but also in the opposed hemispace, Between_Invalid_Different_Hemispace (BIV_DH)]. The results showed that RTs in the WV condition (valid) were significantly slower than RTs in the WIV and BIV_DH (invalid) condition, i.e. a typical IOR, regardless of whether the target appeared in the closer or farther depth plane. However, when attention reoriented along the conditions of BIV_SH, there were typical IOR when targets appeared only in closer depth plane, but not in farther depth plane. Taken together, we showed that attentional reorienting in depth operates as efficiently as in the bi-dimensional space just only when objects that unexpectedly approach observers.