Doctoral Researcher Yuanyuan Zhao and Dr Dietmar Heinke have published a paper contributing to the long-standing debate as to whether IOR is caused by attentional processing or perceptual processing.

If people look for a friend in a crowd they typically check every face and see if it is their friend. To avoid double-checking the brain marks each visited face with a tag called “inhibition of return” (IOR).  The research behind this paper examines what is involved in creating such an IOR. To be more specific, does it require resources demanding attention to initiate an IOR? The experiments demonstrated that attention is not required; instead the brain uses simple (perceptual) processes. This finding underlines the efficiency with which the brain operates in certain tasks, such as looking for a friend in the crowd. 

Reference: Zhao, Y. & Heinke, D. (2014) What causes IOR? Attention or perception? - Manipulating cue and target luminance in either blocked or mixed condition. Vision Research, 105:37–46. 

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