Revisiting the spread of sparing in the attentional blink

The attentional blink (AB) refers to a deficit in reporting the second of two targets (T₂) in a rapid serial visual presentation (RSVP) stream when this target is presented less than 500 ms after the onset of the first target (T₁). It is under debate whether the AB originates from a limitation of cognitive resources or from an attentional suppression process triggered by a distractor or by target discontinuity. In this study, we placed a distractor (D_inter) or an extra target (T_inter) between T₁ and T₂ while at the same time manipulating the time interval between D_inter (or T_inter) and T₂ (0, 200, or 500 ms). The level of attentional enhancement induced by the detection of T₁ was also manipulated by adding external noise to T₁. The results showed that, as compared to the dual-target condition, T₂ performance was better in the consecutive-target condition, when T₂ was close in time to T_inter (i.e., the spread of sparing), but was worse with a longer interval between T₂ and the preceding item. Adding external noise to T₁ improved T₂ performance when T₂ was close in time to the preceding item, irrespective of whether this item was D_inter or T_inter. These findings present difficulties for the existing models of the AB, although the overall pattern observed is generally more consistent with the episodic simultaneous-type, serial-token (eSTST) model than with conventional resource accounts or distractor-based attentional selection accounts of the AB.