Temporal constraints on visual perception: A psychophysical investigation of the relation between attention capture and the attentional blink

When two targets (T1 & T2) are presented in rapidsuccession, observers often fail to report T2 if they attendto T1. The bottleneck theory proposes that this attentionalblink (AB) is due to T1 occupying a slow processing stagewhen T2 is presented. Accordingly, if increasing T1difficulty increases T1 processing time, this should cause agreater AB. The attention capture hypothesis suggests thatT1 captures attention, which cannot be reallocated to T2 intime. Accordingly, if increasing T1 difficulty decreases T1saliency, this should cause a smaller AB. In twoexperiments we find support for an attention capturehypothesis. In Experiment 1 we find that AB magnitudeincreases with T1 contrast – but only when T1 is unmasked.In Experiment 2 we add Gaussian noise to targets and varyT1 contrast but keep T1 ‘s SNR constant. Again we findthat AB magnitude increases with T1 contrast.