Abstract
The relationship between attention and awareness has intrigued scientists for decades. It is suggested that attention and awareness are two dissociated processes (Koch & Tsuchiya, 2007), based on considerations of previous research on voluntary spatial attention. However, such dissociation could be explained by the fact that participants were instructed to attend to the stimulus location denoted by visible markers (Bahrami et al., 2008), and it is known that voluntary spatial attention can affect neural processing in the absence of visual stimuli (Kastner et al., 1999). In addition, people usually do not voluntarily allocate their attention to an object outside awareness under ecological situations. To further elucidate the relationship between attention and awareness, we investigated involuntary attention under both aware and unaware conditions. In the first two experiments, we presented a brief cue with masks such that participants were unaware of the cue. This was followed by a search array, for which participants performed a shape singleton detection task. Although the cue was task-irrelevant and unconscious, we observed faster reaction times when either the cue's location or color was congruent with target. Thus unconscious stimuli can elicit both space- and feature-based attention. In addition, contrary to typical exogenous cueing paradigm, both feature- and space-based cueing effects were detected with a relatively long inter-stimulus-interval (ISI; 500ms) but not with a short ISI (200ms). In a further control experiment, we made the cue visible under both short and long ISIs. Here we found feature and spatial cueing effect only for the long ISI. This suggests that the visual noise from the masks delayed the processing of the cue under both aware and unaware conditions. Overall, our results provide further evidence for the dissociation between attention and awareness.
Meeting abstract presented at VSS 2016