Task switching mediates direct interference of intertarget distractors in the attentional blink: An event-related potential study

The attentional blink (AB) refers to the difficulty in reporting a second target (T2) presented shortly after a first target (T1) in a stream of distractors. The goal of the present study was to investigate distractor-based interference in the AB by recording the P3 component of the event-related potential to both targets. An intertarget distractor was presented at lag 1 (T1+1), at lag 2 (T1+2), or at neither of these two lags (no distractor). T2 was always presented at lag 3, as the last item in the stream. In two experiments, the P3 from T1 was attenuated in the T1+1 condition compared to the two other distractor conditions. In absence of a task switch (Experiment 1), the P3 from T2 was delayed in both the T1+1 and T1+2 conditions. In the presence of a task switch (Experiment 2), the P3 from T2 was delayed only in the T1+1 condition. Results demonstrate that intertarget distractors can modulate the AB directly but only in absence of a task switch.

Temporal variability predicts the magnitude of between-group attentional blink differences in developmental dyslexia: a meta-analysis

Background. Here we report on a meta-analysis of the between-group main effect (Group Difference) noted in the attentional blink (AB) research focused on specific reading impairment, commonly referred to as developmental dyslexia. The AB effect relates to a limitation in the allocation of attention over time and is examined in a dual-target rapid serial visual presentation (RSVP) paradigm. When the second target appears in close temporal proximity to the first target, the second target is reported less accurately. Method. A Web of Science search with terms "attentional blink" & dyslexia returned 13 AB experiments (11 papers) conducted with developmental dyslexia. After exclusions, 12 experiments were included in the meta-analysis. The main pattern of performance from those experiments was lower overall accuracy in groups of individuals with dyslexia relative to typically reading peers; that is, a between-group main effect. This meta-analysis examined the size of the Group Difference in relation to temporal and task-set related features, which differed between and within experiments. Results. Random effects modelling indicated a significant Group Difference of -0.74 standard deviation units, 95% CI [-.96, -.52], p < .001 (excluding one anomalous result): implicating significantly poorer overall dual-target performance in dyslexic readers. Meta-regression analyses indicated two variables related to the Group Difference; pre-RSVP time and temporal variability of the second target relative to the first target within the RSVP. Discussion. It is suggested that the endogenous engagement of the temporal features of task-set is slower or disrupted in developmental dyslexia.

Is the impairment in temporal allocation of visual attention in children with ADHD related to a developmental delay or a structural cognitive deficit?

We investigated the temporal allocation of visual attention in 11-year-old children with attention-deficit/hyperactivity disorder (ADHD) by comparing their attentional blink (AB) parameters (duration, amplitude and minimum performance) with those observed in three groups of healthy control participants (8-year-olds, 11-year-olds and adults). The AB is a marker of impaired ability to detect a second target following the identification of a first target when both appear randomly within a rapid sequence of distractor items. Our results showed developmental effects; with age, the AB duration decreased and the AB minimum moved to shorter lag times. Importantly, 11-year old children with ADHD presented much the same similar AB patterns (in terms of duration and minimum position) as the healthy 8-year-old controls. Our results support the hypothesis whereby impaired allocation of temporal selective attention in children with ADHD is due to a developmental delay and not a specific cognitive deficit.

Mechanisms of visual threat detection in specific phobia

People with anxiety or stress-related disorders attend differently to threat-relevant compared with non-threat stimuli, yet the temporal mechanisms of differential allocation of attention are not well understood. We investigated two independent mechanisms of temporal processing of visual threat by comparing spider-phobic and non-fearful participants using a rapid serial visual presentation task. Consistent with prior literature, spider phobics, but not non-fearful controls, displayed threat-specific facilitated detection of spider stimuli relative to negative stimuli and neutral stimuli. Further, signal detection analyses revealed that facilitated threat detection in spider-phobic participants was driven by greater sensitivity to threat stimulus features and a trend towards a lower threshold for detecting spider stimuli. However, phobic participants did not display reliably slowed temporal disengagement from threat-relevant stimuli. These findings advance our understanding of threat feature processing that might contribute to the onset and maintenance of symptoms in specific phobia and disorders that involve visual threat information more generally.

The more your mind wanders, the smaller your attentional blink: an individual differences study

The present studies investigate the hypothesis that individuals who frequently report experiencing episodes of mind wandering do so because they under-invest attentional/executive resources in the external environment. Here we examined whether self-reported instances of mind wandering predict the magnitude of the "attentional blink" (AB) in a rapid serial visual presentation (RSVP) task, since a prominent view is that the AB derives from an over-investment of attention in the information stream. Study 1 demonstrates that subjective reports of mind wandering in a sustained attention task have a negative predictive relation with respect to the magnitude of the AB measured in a subsequent RSVP task. In addition, using the Spontaneous and Deliberate Mind Wandering Questionnaire in Study 2, we were again able to show that trait-level mind wandering in everyday life negatively predicts AB magnitude. We suggest that mind wandering may be the behavioural outcome of an adaptive cognitive style intended to maximize the efficient processing of dynamic and temporally unpredictable events.

Relative prediction error and protection from attentional blink in human associative learning

The relationship between predictive learning and attentional processing was investigated in two experiments. During a learning procedure participants viewed rapid serial visual presentation (RSVP) of stimuli in the context of a choice-reaction-time (CRT) task. Salient stimuli in the RSVP streams were either predictive or non-predictive for the outcome of the CRT task. Following this procedure we measured attentional blink (AB) to the predictive and non-predictive stimuli. In Experiment 1, despite the use of a large sample and checks demonstrating the validity of the learning procedure and the AB measure, we did not observe reduced AB for predictive stimuli. In contrast, in Experiment 2, where the predictive stimuli occurred alongside salient non-predictive comparison stimuli, we did find less AB for predictive than for non-predictive stimuli. Our results support an attentional model of learning in which relative prediction error is used to increase learning rates for good predictors and reduce learning rates for poor predictors and provide confirmation of the AB learning effect.

Cross-diagnostic comparison of visual processing in bipolar disorder and schizophrenia

Patients with Schizophrenia (SZ) show deficits across various stages of visual information processing. Whether patients with Bipolar Disorder (BD) exhibit these deficits is unclear. In this study, we conducted a detailed comparison of specific stages of early visual perception in BD and SZ. Forty-three BD patients, 43 SZ patients, and 51 matched healthy control subjects (HC) were administered three visual processing paradigms emphasizing: 1) an early stage of object formation (location backward masking), 2) a middle stage of object substitution (four-dot backward masking), and 3) a later stage at the perception-attention interface (rapid serial visual processing (RSVP) task eliciting the attentional blink). SZ performed significantly worse than BD and HC on location and four-dot masking. BD did not significantly differ from HC on either masking task. Both patient groups performed significantly worse than HC on the RSVP task; unlike SZ, BD did not show a significant attentional blink effect compared to HC. Our results indicate that BD patients were intact at the early and middle stages of visual processing (object formation and substitution) but intermediate between the SZ and HC groups at a later processing stage involving perceptual and attentional processes (RSVP task). These findings suggest that SZ is characterized by a diffuse pathophysiology affecting all stages of visual processing whereas in BD disruption is only at the latest stage involving higher order attentional functions.

Masking of a first target in the attentional blink attenuates the P3 to the first target and delays the P3 to the second target

The attentional blink (AB) refers to the decline in report accuracy of a second target (T2) when presented shortly after a first target (T1) in a rapid serial visual presentation (RSVP) of distractors. It is known that masking T1 increases the magnitude of the AB, and masking a single target (equivalent to T1) in a RSVP stream attenuates the P3 to the target in correct trials. The major purpose of the present study was to clarify how these two effects may be integrated. An intervening distractor was presented at lag 1 (T1+1), at lag 2 (T1+2), or at neither of these two lags (no distractor). T2 was always presented at lag 3, as the last item in the stream. The P3 to T1 was attenuated and the P3 to T2 delayed in the T1+1 condition compared to the two other distractor conditions. These results clearly show that masking T1 attenuates the P3 to T1 and delays the P3 to T2 in the AB. Implications for extant theories of the AB are discussed.

Can attenuation of attentional blink also evoke removal of repetition blindness?

A recent study showed that attentional blink (AB), which has been considered to reflect the capacity limitation of visual temporal attention, can be attenuated after a short period of the color-salient training, in which the second target (T2) within the AB period is given a salient color (Choi et al., 2012). The current study explored whether the effect of the color-salient training could be transferred to another phenomenon. In addition to AB, repetition blindness (RB) was employed, which is phenomenologically similar to, but fundamentally different from AB. After completion of the color-salient training with a nonrepeated T2 (corresponding to AB), RB was still observed, whereas AB was completely removed. However, the color-salient training with a repeated T2 (similar to RB) induced not only a significant reduction of RB but also an attenuation of AB. This result provides further evidence for dissociation between AB and RB. In addition, it implies that the color-salient training improves the attentional control mechanism related to target-distractor discrimination rather than to the perceptual system.

Mood-specific effects in the allocation of attention across time

Participants completed single and dual rapid serial visual presentation (RSVP) tasks. Across five experiments, either the mood of the participant or valence of the target was manipulated to create pairings in which the critical target was either mood congruent or mood noncongruent. When the second target (T2) in an RSVP stream was congruent with the participant's mood, performance was enhanced. This was true for happy and sad moods and in single- and dual-task conditions. In contrast, the effects of congruence varied when the focus was on the first target (T1). When in a sad mood and having attended to a sad T1, detection of a neutral T2 was impaired, resulting in a stronger attentional blink (AB). There was no effect of stimulus-mood congruence for T1 when in a happy mood. It was concluded that mood-congruence is important for stimulus detection, but that sadness uniquely influences post-identification processing when attention is first focused on mood-congruent information.

The attentional blink freezes spatial attention allocation to targets, not distractors: evidence from human electrophysiology

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.

Control over experience? Magnitude of the attentional blink depends on meditative state

The information processing capacity of the human mind is limited, as is evidenced by the so-called 'attentional-blink' deficit. This deficit is believed to result from competition between stimuli for limited attentional resources. We examined to what extent advanced meditators can manipulate their attentional state and control performance on an attentional blink task. We compared the magnitude of the attentional blink between states of focused attention meditation (in which one focuses tightly on an object) and states of open monitoring meditation (in which one is simply aware of whatever comes into experience) in a sample of experienced meditators. We found a smaller attentional blink during open monitoring compared to focused attention meditation due to reduced T1 capture. Of note, this effect was only found for very experienced meditators (on average 10,704 h of experience). These data may suggest that very advanced practitioners can exert some control over their conscious experience.

Cognitive architectures as a tool for investigating the role of oscillatory power and coherence in cognition

In contrast to our increasing knowledge of the role that oscillations in single brain regions play in cognition, very little is known about how coherence between oscillations in distant brain regions is related to information transmission. Here I present a cognitive modeling approach that can address that question. Specifically, I show how a model of the attentional blink implemented in the ACT-R cognitive architecture is related to the amplitude and coherence of EEG oscillations. The dynamics of the model's working memory resource is primarily associated with parietal 4-9 Hz theta oscillations, while the dynamics of the model's declarative memory, visual perception and procedural resources together are correlated with posterior theta oscillations. I further show that model predictions about inter-module communication during the processes of stimulus identification and target consolidation are associated with selective increases in coherence at the predicted points in time.

The change of attentional blink and repetition blindness after cerebellar lesions

Attentional blink is the failure to identify a second target following a first target when both have appeared in a rapid serial visual presentation (RSVP) task. Repetition blindness is an additional difficulty to recognize the second same target in a RSVP task. Attentional blink and repetition blindness have many phenomenal similarities and can be experimentally dissociated. Repetition blindness may reflect the visual information processing stage prior to the central limitation stages. Many studies suggest that the cerebellum is involved in cognitive abilities, including attentional blink. fMRI studies have shown cerebellum activation in RSVP tasks, but the details of how the cerebellum is involved in the mechanism of attentional blink is unclear. In this study, we investigated attentional blink and repetition blindness performance in 10 patients with focal lesions of the cerebellum and 10 healthy controls using the RSVP task. Patients with cerebellar lesions demonstrated a longer attentional blink duration and a larger magnitude compared with controls. The performance of repetition blindness was lower than that of attentional blink in the control group, but the differences between the attentional blink and repetition blindness conditions in the patient group had no significance. The performance of repetition blindness between the two groups showed no significance. These data indicate that the cerebellum may be related to the central processing stage of visual temporal attention. Also, we provide new evidence to support the idea that the cerebellum is involved in non-motor functions.

Do social utility judgments influence attentional processing?

Research shows that social judgments influence decision-making in social environments. For example, judgments about an interaction partners' trustworthiness affect a variety of social behaviors and decisions. One mechanism by which social judgments may influence social decisions is by biasing the automatic allocation of attention toward certain social partners, thereby shaping the information people acquire. Using an attentional blink paradigm, we investigate how trustworthiness judgments alter the allocation of attention to social stimuli in a set of two experiments. The first experiment investigates trustworthiness judgments based solely on a social partner's facial appearance. The second experiment examines the effect of trustworthiness judgments based on experienced behavior. In the first, strong appearance-based judgments (positive and negative) enhanced stimulus recognizability but did not alter the size of the attentional blink, suggesting that appearance-based social judgments enhance face memory but do not affect pre-attentive processing. However, in the second experiment, in which judgments were based on behavioral experience rather than appearance, positive judgments enhanced pre-attentive processing of trustworthy faces. This suggests that a stimulus's potential benefits, rather than its disadvantages, shape the automatic distribution of attentional resources. These results have implications for understanding how appearance- and behavior-based social cues shape attention distribution in social environments.