Low prevalence targets are primarily missed due to mind wandering

The impact of target prevalence (the proportion of trials in which a target appears) has been widely studied within visual search. The low prevalence effect is the finding that rare targets are often missed. Mind wandering, where one’s attention drifts away from a primary goal, impairs performance across various tasks, but its influence in low-prevalence search remains unclear. We recruited 60 participants from the general population and examined their mind-wandering rates as they searched for either low- (10%) or high- (50%) prevalence targets. When participants were engaged in mind wandering, response accuracy was reduced and target-absent response times increased. Low-prevalence targets were missed more than high-prevalence targets, but to our surprise, we discovered that most of the low-prevalence effect could be attributed to mind wandering in the majority our analyses. This marks a substantial shift in our understanding of the prevalence effect.