Abstract
A long line of empirical evidence suggests that all items presented during the attentional blink (AB) are processed to a semantic, or post-perceptual, level. This evidence has led to the common theoretical assumption that the level of selection during the AB is fixed at a post-perceptual stage. However, recent evidence suggests that first target (T1) task difficulty modulates post-perceptual processing during the AB - a finding that suggests that the level of selection during the AB is flexible. These recent studies have used either spatial manipulations or task switches between T1 and the second target (T2) thereby raising the possibility that the influence of T1-difficulty on post-perceptual processing during the AB might be determined solely by these factors rather than due to T1-difficutly. To test whether the influence of T1-difficulty on post-perceptual processing during the AB can occur in the absence of either of these factors, 61 participants performed a standard RSVP task in which both the T1 and T2 tasks involved identifying a red or green letter in a stream of white distractors. Critically, T1-task difficulty was manipulated and the influence of T1-difficulty on the processing of subsequent information was assessed by inserting a white priming distractor with the same identity as the T2 on half of the trials. Replicating previous work (Dux & Marois, 2008), T2 accuracy was higher during the AB when it was preceded by a prime than when it was not. Importantly, under conditions of high T1-difficulty the influence of the prime was decreased. These results suggest that T1-difficulty is an important factor that determines if information presented during the AB is processed to a post-perceptual level. Moreover, these results support the notion that the level of processing during the AB is not fixed, but rather is flexible.