Using inattentional blindness as an operational definition of unattended: The case of a response–end effect

Abstract

Inattentional blindness (IB), which is the lack of awareness of stimuli that appear in unattended regions of the visual field, can be used as an operational definition of unattended. Using separate online measures in combination with IB can be used to probe specific aspects of processing that are engaged by unattended stimuli. Previous applications of this method have provided evidence that unattended stimuli can engage processes that lead to grouping‐by‐similarity (Moore & Egeth, 1997), as well as processes involved in the perceptual completion of partially visible surfaces (Moore, Grosjean, & Lleras, 2003). Here we applied this method to address the question of whether unattended stimuli can engage response–end processes. Specifically, we used a stimulus–response compatibility effect, the Simon effect (e.g., Simon & Rudell, 1967), as an online measure of response selection. As assessed through this measure, unattended stimuli failed to engage response‐selection processes.