Masking in the attentional blink: implications for a preconscious memory buffer

In the attentional blink (AB) perception of the second of two visual targets (T2) is impaired if presented within about 500ms of the first (T1). We adopted the hypothesis that, during that period, a representation of T2 is stored in a preconscious buffer (PCB) while T1 is processed. We studied the characteristics of the PCB by asking what types of visual masking interfere with the stored memory representation. We investigated three masking procedures: delayed pattern masking, delayed metacontrast, and common-onset metacontrast masking. Delayed masks trigger onset transients in low-level vision, whereas common-onset masks involve mainly higher-level visual areas. The results showed that the AB occurred with all three procedures, strongly suggesting that neither overlap of contours between target and mask nor unique onset transients triggered by the trailing mask are necessary to produce an AB deficit. We conclude that the most likely locus of the PCB is in high-level vision.