More power to the unconscious: conscious, but not unconscious, exogenous attention requires location variation

Substantial evidence suggests that unconscious processing can be characterized as a lesser or weaker version of conscious processing. To test this notion, we designed a novel repeated-cuing procedure based on exogenous attention: The location of the attentional cue was first fixed across blocks (fixed-cue blocks), and then the cue was removed in subsequent blocks (no-cue blocks). The visibility of the cue was also manipulated. We found that when the cue was invisible, the response to a prespecified stimulus in the fixed-cue blocks was faster if the stimulus was at the cued location than if it was at the uncued location. But when the cue was visible, this cuing effect was abolished, potentially because of an awareness-dependent, location-based inhibition mechanism, as revealed by an attentional bias against the previously cued location in the no-cue blocks. We call this bias negative attentional aftereffect. These results provide novel evidence against the weaker-version characterization of unconscious effects, highlighting dissociable components of orienting and inhibition in exogenous cuing through awareness and temporal dynamics.