Abstract
We investigated how ignored objects are processed, by examining priming from a distractor under rapid serial visual presentation (RSVP) conditions. Subjects performed a dual-target RSVP task in which they were required to report two red target objects embedded within streams of black object distractors. Target 1 was an upright object, while Target 2 and the distractors appeared in different orientations. On a proportion of trials, one of the distractors (priming distractor) in the stream had the same identity as Target 2 and was presented either in the same orientation or rotated by 90°. In Experiment 1, the priming distractor occurred prior to Target 1 (serial position T1–2), and resulted in Target 2 accuracy being enhanced when the priming distractor had a different orientation to Target 2, but not when it had the same orientation. These results indicate that orientation-invariant information extracted from an ignored distractor can prime a later target. However, this priming effect appeared to be moderated by attentional suppression of distractors, leading to a loss of priming when the priming distractor was identical to Target 2 (same identity and orientation). To test this, in a second experiment, we examined the influence of the priming distractor when it was presented within the attentional blink, where distractor suppression is impaired (Dux & Harris, 2007). When the priming distractor was presented at Lag 2 and Target 2 appeared at Lag 4, there was equal positive priming for the second target regardless of the orientation of the priming distractor. The findings suggest that object identity and orientation are at least partially independent and that attention plays an important role in the representation of object orientation.
Funded by ARC grant DP0557590.