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It is widely reported that face recognition relies on two dissociable mechanisms, the featural and the configural processing. However, it is unclear whether these two processing types involve different neural mechanisms and are differently modulated by attentional resources. Using the attentional blink (AB) paradigm, we aimed to investigate the effect of attentional resources on configural and featural face processing by recording event-related potentials (ERPs). The amount of attentional resources was manipulated as deficient or sufficient by presenting the second target (T2) in or out of the AB period, respectively. We found that in addition to a traditional P3 attention effect, the amplitude of N170/VPP to the T2 stimuli was also sensitive to attentional resources, suggesting that attention affects face processing at an earlier perceptual processing stage. More importantly, configural face processing elicited a larger posterior P1 compared to featural face processing, but only when the attentional resources were sufficient. In contrast, the anterior N1 was larger for configural relative to featural face processing only when the attentional resources were deficient. These results suggest that early stages of configural and featural face processing are differently modulated by attentional resources, possibly with different underlying mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: Previous work found a significant reduction of the amplitude of the N2pc ERP component during the attentional blink in response to lateral visual targets, suggesting that the allocation of attention to visual targets is impaired during the attentional blink. Recent theorizing on the processes reflected by the N2pc suggests the possibility of distinct sets of neural mechanisms underlying its generation, one responsible for target activation, and one for distractor inhibition. To disentangle whether either or both of these mechanisms are impaired during the attentional blink, an RSVP sequence of circles, equidistant from fixation was used. The first target frame (T1) contained the same repeated target colour circle and target whereas the second target frame (T2) contained a distractor colour singleton as well as a target colour singleton. Only the target or only the distractor was presented at a lateral position; the other singleton was presented on the vertical midline so as not to elicit any event-related lateralization. Impaired T2 report accuracy at a short stimulus-onset asynchrony (SOA) was accompanied by a significant delay of the N2pc to lateral T2 targets when compared to a long SOA condition. No such delay was found when the lateralized stimulus was a distractor, suggesting that the attentional blink impacts attention allocation to targets, not distractors. We also observed a lateralized component earlier than the N2pc, a posterior contralateral positivity (Ppc) that did not depend on T1–T2 SOA and that was elicited by both lateral targets and distractors. We conclude that, contrary to N2pc, the Ppc likely reflects activity of bottom-up mechanisms responding unselectively to asymmetrical visual displays. [Copyright &y& Elsevier]

Abstract: Accuracy for a second target (T2) is reduced when it is presented within 500ms of a first target (T1) in a rapid serial visual presentation (RSVP)—an attentional blink (AB). Reducing the amount of attentional investment with an additional task or instructing the use of a more relaxed cognitive approach has been found to reduce the magnitude of the AB. As well, personality and affective traits, as well as affective states, associated with a more diffused or flexible cognitive approach have been found to predict smaller AB magnitudes. In the current study, event-related desynchronization in the alpha range was used to investigate whether the degree of attentional investment in anticipation of a RSVP trial was related to the behavioral outcome of that trial. As hypothesized, greater alpha ERD before the RSVP trial, indicating greater anticipatory attentional investment, was observed on short lag trials where an AB was present (inaccurate T2 performance) compared to short lag trials where an AB did not occur. However, on trials where T2 was presented after a longer period relative to T1, greater alpha ERD before the RSVP trial was found on trials with accurate T2 performance. Results support models of the AB that propose that greater attentional investment underlies the AB, and furthermore that this attentional investment is prepared in anticipation before each RSVP trial. [Copyright &y& Elsevier]

Abstract: The second of two targets (T2) presented in a rapid visual stream is often missed when presented shortly after the first (T1). This phenomenon has been referred to as the attentional blink. Here we show that the presentation of a synchronous sound enables T2 to escape the attentional blink, to the extent that performance was back at the level of T1. The sound also improved T1 identification, with little evidence for a trade-off between T1 and T2. Improvements were also found even if the sounds coincided with distractors on 82% of the trials, suggesting an automatic component. Sounds that preceded the targets had little to no effect on T2, suggesting that the enhancement was not due to alerting. These findings replicate and extend earlier work on audition-driven perceptual enhancement of single visual targets. They also have implications for theories of the attentional blink. [Copyright &y& Elsevier]

Abstract: There is considerable current interest in neural modeling of the attentional blink phenomenon. Two prominent models of this task are the Simultaneous Type Serial Token (ST2) model and the Locus Coeruleus–Norepinephrine (LC–NE) model. The former of these generates a broad spectrum of behavioral data, while the latter provides a neurophysiologically detailed account. This paper explores the relationship between these two approaches. Specifically, we consider the spectrum of empirical phenomena that the two models generate, particularly emphasizing the need to generate a reciprocal relationship between bottom-up trace strength and the blink bottleneck. Then we discuss the implications of using ST2 token mechanisms in the LC–NE setting. [Copyright &y& Elsevier]

Abstract: In order to investigate the interplay between visuo-spatial attention and central attention, we varied the relative probability (25% vs. 75%) of the responses to lateralized targets in an attentional blink paradigm. When the first target was associated with a less probable response, we observed a larger attentional blink, that is, a general reduction in accuracy for the second target. The efficiency of deployment of spatial attention to the second target was also reduced as a function of the response frequency for the first target. Both the N2pc, an event-related potential (ERP) associated with the deployment of attention in visual space, and the SPCN (sustained posterior contralateral negativity), an ERP associated with the maintenance of information in visual short-term memory, time-locked to T2 were significantly reduced when the first target was associated with a less frequent response. Furthermore, the P3 ERP to T2 was abolished when the response to T1 was rare but not when it was frequent. The results show that the association of T1 to either a rare or frequent response causes significant interference with the deployment of visual spatial attention to T2, and with the short-term consolidation of T2 into visual short-term memory. [Copyright &y& Elsevier]

Abstract: When two targets have to be identified in a rapid serial visual presentation (RSVP) paradigm, perception of the second target (T2) becomes significantly impaired if it is displayed 200–500 ms after the first target (T1), a phenomenon labeled as “Attentional Blink” (AB). Here we investigate 14 spider phobics and 16 controls in an RSVP paradigm with neutral T1s. T2 pictures were neutral, emotional (positive or negative) or threatening (spiders for spider phobics). In addition, event-related potentials in response to T2 targets were analyzed. Both spider phobics and controls correctly identified positive and negative T2s more often than neutral T2s, indicating a reduction of the AB effect caused by emotional stimuli. In addition, spider phobics detected spider T2s more frequently than all other T2s. Furthermore, significantly larger P300 amplitudes accompanied detection of spider T2s in the spider phobics as compared to the controls. Based on recent theoretical accounts of the AB effect, results indicate a phobia-related post-perceptual consolidation bias of threatening information in spider phobic subjects. [Copyright &y& Elsevier]

Abstract: A rapid serial visual presentation technique was used to display sequentially two targets, T1 and T2, and monitor P3 amplitude and latency variations associated with the attentional blink (AB) effect. A red T1 digit was embedded on each trial in a sequence of black letters. T2 was either masked by a trailing stimulus or not masked. T1 had to be identified on a proportion of trials, or ignored in other trials. T2 was the black letter ‘E’ on 20% of the trials, or any other non-‘E’ black letter in the other 80% of the trials. A delayed ‘E’ detection task was required at the end of each trial. An AB was observed when T1 had to be reported and T2 was masked. The AB effect was associated with a sizable amplitude reduction of the P3 component time locked to T2 onset. When T2 was not masked, no AB or P3 amplitude variations were observed. When T1 had to be reported, a delayed P3 peak latency was observed at short compared to long T1–T2 intervals. No effect of T1–T2 interval was observed on the T2-locked P3 peak latency when T1 could be ignored. Taken together these findings provide converging evidence in support of temporal attention models bridging behavior and electrophysiology that postulate a direct link between the cause of the AB effect and the sources of both amplitude and latency variations in the T2-locked P3 component. [Copyright &y& Elsevier]

Abstract: During transparent motion, attention to changes in the direction of one illusory surface will impede recognition of a similar event affecting the other surface if both are close together in time. This is a form of object-based attentional blink (AB). Here, we show that this AB is related to a smaller N200 response to the change in direction and that the response is even smaller for trials on which the subject makes mistakes compared to those with correct responses consistent with signal detection theory models. The variation of N200 associated with the AB can be modeled by an attenuation of current sources estimated in visual extrastriate cortex. These results suggest that the AB in the transparent motion paradigm is due to the suppression of sensory signals in early visual areas. [Copyright &y& Elsevier]