Value-modulated attentional capture depends on explicit awareness

Value-modulated attentional capture (VMAC) reflects a process by which a priori neutral stimuli gain attentional priority when associated with reward, independently of goal or stimulus-driven attentional control. Although VMAC has been classically considered an automatic and implicit process, the nature of the underlying learning process remains unclear. For instance, VMAC could be driven by the stimulus predictive value alone (Pavlovian learning) or, alternatively, by the automatization of an instrumental response to the associated stimulus (an attentional habit). Although recent research has demonstrated that it is possible to observe VMAC when the associated stimulus is response-irrelevant, to our knowledge, the role of the informational value of the associated stimulus during learning remains unexplored. In a well-powered replication of a previous study, we found that VMAC disappears when participants are not explicitly informed about the stimulus-reward contingency in the pre-task instructions. In a second experiment, we show that when instructions are manipulated between groups, only the instructed group shows VMAC. Interestingly, although the no-instruction group did not show VMAC at the group level, participants who became aware of the stimulus-reward contingencies did show robust VMAC at the end of the task. Meta-analytic evidence further supports our conclusion by showing that when stimulus-reward contingencies are included in the instructions the effect size of reward-driven distraction increases. Taken collectively, these findings suggest that the learning process behind VMAC may not be entirely implicit.