Spatial attention freezes during the attention blink

Abstract

A variant of the rapid serial visual presentation paradigm was used to display sequentially two lateral sequences of stimuli, one to the left and one to the right of fixation, embedding two pairs of target stimuli, T1 and T2. T1 was composed of a pair of alphanumeric characters, and subjects had either to ignore T1 or to encode T1 for a delayed response. T2 was a lateral square of a prespecified color. The square had a small gap in one side, and the task for this stimulus was to report which side had the gap. When subjects were required to ignore T1, the T2-locked ERP produced a clear N2pc, that is, a greater negativity at electrode sites contralateral to the position occupied by T2. This N2pc was followed by a sustained posterior contralateral negativity (SPCN). When subjects were required to monitor T1 in addition to T2, both the N2pc and the SPCN components amplitude depended on the difficulty of the task associated with T1. If T1 was composed of digits that had to be encoded for a delayed same/different judgment, both the N2pc and the SPCN components were entirely suppressed. Although attenuated, such components were present when T1 was composed of a pair of symbols that subjects could disregard. The results suggest that a set of mechanisms subserving the allocation of attention in the spatial domain, resulting in the N2pc, suffer significant interference from concurrent cognitive operations required to encode information into visual short-term memory.

The interplay of attention and consciousness in visual search, attentional blink and working memory consolidation

“…These effects are supported by the experimentally observed suppression ('freezing') of the N2pc during the AB period [136,137]. During this period, amplification and ignition in the visual system involving LIP, FEF and the pulvinar are disabled.…”

“…When the GW router for top-down attention is disabled, amplification and ignition processes related to attention cannot take place in the VAW. Indeed, there is evidence of suppression ('freezing') of the N2pc component, related to (spatial) attentional selection in the visual cortex, during the AB [136,137].…”

On the automaticity of contingent capture: disruption caused by the attentional blink

“…Furthermore, studies have shown that spatial attention is "frozen" for the first 100 ms of the AB (Du & Abrams, 2010a). Event-related potential studies have also shown that voluntary orienting during the AB is associated with a decreased N2pc magnitude, further showing the susceptibility of these mechanisms to disruption (Dell'Acqua, Sessa, Jolicoeur, & Robitaille, 2006).…”

The attentional blink and lag 1 sparing are nonspatial

“…Thus, even a cued switch was accompanied by a cost, probably reflecting the difficulty observers have with disengaging from the location of the still relevant T1 (which obviously did not move with the cue). Work by Dell'Acqua et al (2006) has shown that a relevant T1 induces larger switch costs than does a T1 that can be disregarded. What is more, performance at lag 1 in the cued switch condition appeared to be even worse than that in the uncued switch condition in Experiment 2A.…”