Inattentional blindness as a function of proximity to the focus of attention.

The effect of the distance between the center of the focus of attention and an unexpected stimulus on detection was examined in two experiments with the use of the inattentional-blindness paradigm [Mack and Rock, 1998 Inattentional Blindness (Cambridge, MA: MIT Press)]. In experiment 1, the closer a stimulus was to the center of attention, the more likely it was to be detected. Experiment 2 replicated this finding and controlled for retinal eccentricity. These results suggest that low-level stimulus characteristics (e.g. location) may play an important role in the detection of unexpected stimuli. The data are consistent with previous research on the spatial aspects of attention demonstrating that the distance to the focus of attention is a critical variable. This study demonstrates that the effect of distance is similar under conditions of inattention. Theories put forward to explain inattentional blindness should include 'early' attentional factors, as well as factors resulting from later stages of processing.