Action video games and posterior parietal cortex neuromodulation enhance both attention and reading in adults with developmental dyslexia.

The impact of action video games on reading performance has been already demonstrated in individuals with and without neurodevelopmental disorders. The combination of action video games and posterior parietal cortex neuromodulation by a transcranial random noise stimulation could enhance brain plasticity, improving attentional control and reading skills also in adults with developmental dyslexia. In a double blind randomized controlled trial, 20 young adult nonaction video game players with developmental dyslexia were trained for 15 h with action video games. Half of the participants were stimulated with bilateral transcranial random noise stimulation on the posterior parietal cortex during the action video game training, whereas the others were in the placebo (i.e. sham) condition. Word text reading, pseudowords decoding, and temporal attention (attentional blink), as well as electroencephalographic activity during the attentional blink, were measured before and after the training. The action video game + transcranial random noise stimulation group showed temporal attention, word text reading, and pseudoword decoding enhancements and P300 amplitude brain potential changes. The enhancement in temporal attention performance was related with the efficiency in pseudoword decoding improvement. Our results demonstrate that the combination of action video game training with parietal neuromodulation increases the efficiency of visual attention deployment, probably reshaping goal-directed and stimulus-driven fronto-parietal attentional networks interplay in young adults with neurodevelopmental conditions.

Total sleep deprivation effects on the attentional blink.

The Attentional Blink (AB) is a phenomenon that reflects difficulty in detecting or identifying the second of two successive targets (T1 and T2) that are presented in rapid succession, between 200-500ms apart. The AB involves indicators of attentional and temporal integration mechanisms related to the early stages of visual processing. The aim of this study was to identify the effects of 24-h of sleep deprivation (total sleep deprivation, TSD) on the attentional and temporal integration mechanisms of the AB. Twenty-two undergraduate students were recorded during five successive days, in these three conditions: baseline (two days), TSD (one day), and recovery (two days). Each day, at around 12:00 h, participants responded to a Rapid Serial Visual Presentation task (RSVP) that presented two targets separated by random intervals from 100 to 1000ms. The attentional mechanisms were assessed by the AB presence, the AB magnitude, and the AB interval, while the temporal integration mechanisms were evaluated by lag-1 sparing and order reversal responses. TSD negatively affected the attentional mechanisms, which is expressed by an overall reduction in performance, an extended AB interval, and a reduced AB magnitude. TSD also negatively affected the temporal integration mechanisms, manifested by an absence of lag-1 sparing and an increase in order reversals. These results suggest that people are still able to respond to two successive stimuli after 24 h without sleep. However, it becomes more difficult to respond to both stimuli because the attentional and temporal integration mechanisms of the AB are impaired.

The role of distractors in rapid serial visual presentation reveals the mechanism of attentional blink by EEG-based univariate and multivariate analyses.

Attentional blink pertains to the performance of participants with a severe decline in identifying the second target presented after the first target reported correctly within 200-500 ms in a rapid serial visual presentation. The current study was conducted to investigate the neural mechanism of the effect of the distractor (D1) that immediately follows first target to attentional blink by altering whether D1 was substituted with a blank with electroencephalography recording. The results showed that D1 interfered with the attentional enhancement and working memory encoding in both single-target rapid serial visual presentation task and dual-target rapid serial visual presentation task, which were mainly manifested in delayed and attenuated P3a and diminished P3b of first target. Single-trial analysis indicated that first target and second target will compete with each other for working memory encoding resources in short lag, but not in the long lag. In addition, D1 interfered with the working memory encoding of second target under short lag rather than long lag in the dual-target rapid serial visual presentation task. These results suggested that attentional blink can be attributed to the limited working memory encoding resource, whereas the amount of available resources is subject to modulation by attention. The D1 hinders the attention enhancement of first target, thereby exacerbating attentional blink.

The brain network underlying attentional blink predicts symptoms of attention deficit hyperactivity disorder in children.

Attention deficit hyperactivity disorder (ADHD) is a chronic neuropsychiatric disease that can markedly impair educational, social, and occupational function throughout life. Behavioral deficits may provide clues to the underlying neurological impairments. Children with ADHD exhibit a larger attentional blink (AB) deficit in rapid serial visual presentation (RSVP) tasks than typically developing children, so we examined whether brain connectivity in the neural network associated with AB can predict ADHD symptoms and thus serve as potential biomarkers of the underlying neuropathology. We first employed a connectome-based predictive model analysis of adult resting-state functional magnetic resonance imaging data to identify a distributed brain network for AB. The summed functional connectivity (FC) strength within the AB network reliably predicted individual differences in AB magnitude measured by a classical dual-target RSVP task. Furthermore, the summed FC strength within the AB network predicted individual differences in ADHD Rating Scale scores from an independent dataset of pediatric patients. Our findings suggest that the individual AB network could serve as an applicable neuroimaging-based biomarker of AB deficit and ADHD symptoms.

Self-prioritization effect in the attentional blink paradigm: Attention-based or familiarity-based effect?

The self-prioritization effect (SPE) refers to the advantage in processing stimuli associated with oneself. Here, we addressed the SPE in an attentional blink (AB) task. In Experiment 1, shapes associated to you, friend, or stranger served as T1, and letter X as T2. The AB effect was larger for you than the other label conditions, and larger for friend condition than for stranger condition. We suggest that self-associated shape increased its perceptual salience, producing greater attentional capture. In Experiment 2 participants trained with a shape-label matching task to increase familiarity with the shape-label associations before performing the AB task. The difference between friend and stranger conditions disappeared, suggesting that the difference between the two conditions observed in Experiment 1 was mainly due to differences in familiarity or frequency of use. Importantly, the advantage of you over friend and stranger conditions remained, suggesting that the SPE is a genuine effect.

Attentional blur and blink: Effects of adaptive attentional scaling on visual awareness.

Attentional scaling is a crucial mechanism that enables us to flexibly allocate our attention to larger or smaller regions in the visual field. Although previous studies have demonstrated the critical role of attentional scaling in visual processing, its impact on modulating visual awareness is not yet fully understood. This study investigates the adaptive control of attentional scaling and its influence on visual awareness in an attentional blink paradigm. Participants were required to attend to the first target's location, which was manipulated either session-wise, trial-wise, or such that it could be learned across a block of trials. Discrete, all-or-none, awareness was expected when attention was allocated to a narrow area, while gradual awareness was expected when attention was allocated to a larger area. We used mixture modeling to assess second target awareness across these different attentional scales. The results revealed that participants could adaptively control their attentional scale both across stable sessions, and through (implicit) statistical learning in blocks of successive trials. This produced gradual perceptual awareness when the participants adopted a broad attentional scale, causing an attentional "blur". However, trial-wise cues did not allow for attentional scaling, resulting in more discrete target perception overall, and an attentional "blink". We conclude that the attentional scale is to some extent under adaptive control during the attentional blink/blur, where it can produce qualitatively different modes of perceptual awareness.

Proactive control: Endogenous cueing effects in a two-target attentional blink task.

This study examined proactive control in a two-target task using an endogenous cueing method. Participants identified two target words (T1 then T2) presented in rapid succession. T1 was presented alone or interleaved with a distractor word. In Experiment 1, informative pre-cues that signalled T1 selection difficulty were randomly intermixed with uninformative pre-cues. The results revealed a cueing effect for both T1 and T2, with better performance for informative cues than for uninformative cues. In Experiment 2, informative and uninformative cues were mixed for one group, and blocked for another group. In the mixed cue group, we again found a T2 cueing effect. In the blocked cue group, a cueing effect was observed for both T1 and T2, with the T2 cueing effect restricted to the shortest T1-T2 SOA. The results demonstrate that pre-cues of attentional conflictcan modulate performance in a two-target task used to measure the attentional blink.

Confidence for intrusion errors during the attentional blink depends on target-defining features.

Research surrounding the attentional blink phenomenon - a deficit in responding to the second of two temporally proximal stimuli when presented 150-500 ms after the first - has used a wide variety of target-defining and response features of stimuli. The typical U-shape curve for absolute performance is robust, surviving across most stimulus features, and therefore changes in performance are discussed as dynamics in an attentional system that are nonspecific a stimulus type. However, the patterns of errors participants make might not show the same robustness, and participants' confidences in these errors might differ - potentially suggesting the involvement of different attentional or perceptual mechanisms. The present research is a comparison of error patterns and confidence in those errors when letter target stimuli are defined by either the color of the letter, the presence of a surrounding annulus, or the color of the annulus. Across three experiments, we show that participants erroneously report stimuli that are further away from T2 and they are similarly confident in specifically their post-target errors as their correct responses when annuli define targets, but not when color of the letter defines targets. Experiment 3 provides some evidence to suggest that this error pattern and associated confidence is time-dependent when the color of the annulus defines the target, but not when the color of the letter defines the target. These results raise questions concerning the nature of the errors and possibly the mechanisms of the attentional blink phenomenon itself.

Distrust before first sight? Examining knowledge- and appearance-based effects of trustworthiness on the visual consciousness of faces.

The present EEG study with 32 healthy participants investigated whether affective knowledge about a person influences the visual awareness of their face, additionally considering the impact of facial appearance. Faces differing in perceived trustworthiness based on appearance were associated with negative or neutral social information and shown as target stimuli in an attentional blink task. As expected, participants showed enhanced awareness of faces associated with negative compared to neutral social information. On the neurophysiological level, this effect was connected to differences in the time range of the early posterior negativity (EPN)-a component associated with enhanced attention and facilitated processing of emotional stimuli. The findings indicate that the social-affective relevance of a face based on emotional knowledge is accessed during a phase of attentional enhancement for conscious perception and can affect prioritization for awareness. In contrast, no clear evidence for influences of facial trustworthiness during the attentional blink was found.

Attentional blink in infants under 7 months.

Attentional blink manifests in infants at 7 months of age, indicating that the working memory capacity of 7-month-olds is comparable to that of adults. However, attentional blink in infants under 7 months is not well understood. In this study, we conducted two experiments to investigate attentional blink in 5- and 6-month-old infants. The results of Experiment 1 demonstrated that attentional blinks were not observed with either a short lag (200 ms) or a long lag (800 ms). This suggests that 5- and 6-month-olds are unable to consolidate both targets regardless of the temporal distance between the two. We then split the infants into two groups by their age and conducted Experiment 2 with infants aged younger and older than 180 days to compare their consolidating ability to observe whether they could recognize a single item at 100-ms speed by presenting the same visual stream that was used in Experiment 1 except that one target was eliminated. The results showed that infants over 180 days of age could identify a single target in the visual stream at 100-ms presentation speed, whereas infants under 180 days could not. The findings of the current study indicate that the limitation of working memory capacity in infants under 7 months of age is a possible reason for the lack of attentional blink.

Impact of inhibition level on field-dependent and field-independent individuals in attentional blink.

The attentional blink (AB) phenomenon is a cognitive limitation that refers to the failure in identifying the second target if it follows the first one in close temporal proximity (200-500 ms). However, more recent studies have demonstrated that AB task performance greatly differs among individuals. This behavioral heterogeneity in AB has promoted research on exploring the predictive value of individual differences. The present study examined how AB magnitudes were related to personal cognitive styles. The Embedded Figures Test was carried out to classify participants' cognitive styles, along with the manipulation of the physical characteristics of distractors in the rapid serial visual presentation paradigm (RSVP) as two levels of inhibition (target-distractor similarity). Results from two experiments of varying difficulty revealed that the AB effect varied between field-dependent (FD) and field-independent (FI) individuals. The AB magnitude in FD individuals was more easily influenced by different inhibition levels of distractors, compared to the FI individuals. Results are interpreted in terms of the contemporary theories of AB that highlighted the inhibitory control over attention.

A key role of the hippocampal P3 in the attentional blink.

The attentional blink (AB) refers to an impaired identification of target stimuli (T2), which are presented shortly after a prior target (T1) within a rapid serial visual presentation (RSVP) stream. It has been suggested that the AB is related to a failed transfer of T2 into working memory and that hippocampus (HC) and entorhinal cortex (EC) are regions crucial for this transfer. Since the event-related P3 component has been linked to inhibitory processes, we hypothesized that the hippocampal P3 elicited by T1 may impact on T2 processing within HC and EC. To test this hypothesis, we reanalyzed microwire data from 21 patients, who performed an RSVP task, during intracranial recordings for epilepsy surgery assessment (Reber et al., 2017). We identified T1-related hippocampal P3 components in the local field potentials (LFPs) and determined the temporal onset of T2 processing in HC/EC based on single-unit response onset activity. In accordance with our hypothesis, T1-related single-trial P3 amplitudes at the onset of T2 processing were clearly larger for unseen compared to seen T2-stimuli. Moreover, increased T1-related single-trial P3 peak latencies were found for T2[unseen] versus T2[seen] trials in case of lags 1 to 3, which was in line with our predictions. In conclusion, our findings support inhibition models of the AB and indicate that the hippocampal P3 elicited by T1 plays a central role in the AB.

Perceptual Awareness Occurs Along a Graded Continuum: No Evidence of All-or-None Failures in Continuous Reproduction Tasks.

Does sensory information reach conscious awareness in a discrete, all-or-nothing manner or a gradual, continuous manner? To answer this question, we examined behavioral performance across four different paradigms that manipulate visual awareness: the attentional blink, backward masking, the Sperling iconic memory paradigm, and retro-cuing. We then asked how well we could account for participants' (N = 112 adults) behavior using a signal detection framework that factors in psychophysical scaling to model participants' responses along a single continuum. We found that this model easily accounted for the data from each of these diverse paradigms. Moreover, we reanalyzed the data from prior studies that had posited a discrete view of perceptual awareness and found that our continuous signal detection model outperformed the models that had been used to support an all-or-nothing view of consciousness. This set of data is consistent with the idea that conscious awareness occurs along a graded continuum.

A simple model of the attentional blink and its modulation by mental training.

The attentional blink (AB) effect is the reduced probability of reporting a second target (T2) that appears shortly after a first one (T1) within a rapidly presented sequence of distractors. The AB effect has been shown to be reduced following intensive mental training in the form of mindfulness meditation, with a corresponding reduction in T1-evoked P3b brain potentials. However, the mechanisms underlying these effects remain unknown. We propose a dynamical-systems model of the AB, in which attentional load is described as the response of a dynamical system to incoming impulse signals. Non-task related mental activity is represented by additive noise modulated by meditation. The model provides a parsimonious computational framework relating behavioral performance, evoked brain potentials and training through the concept of reduced mental noise.

Human voices escape the auditory attentional blink: Evidence from detections and pupil responses.

Attentional selection of a second target in a rapid stream of stimuli embedding two targets tends to be briefly impaired when two targets are presented in close temporal proximity, an effect known as an attentional blink (AB). Two target sounds (T1 and T2) were embedded in a rapid serial auditory presentation of environmental sounds with a short (Lag 3) or long lag (Lag 9). Participants were to first identify T1 (bell or sine tone) and then to detect T2 (present or absent). Individual stimuli had durations of either 30 or 90 ms, and were presented in streams of 20 sounds. The T2 varied in category: human voice, cello, or dog sound. Previous research has introduced pupillometry as a useful marker of the intensity of cognitive processing and attentional allocation in the visual AB paradigm. Results suggest that the interplay of stimulus factors is critical for target detection accuracy and provides support for the hypothesis that the human voice is the least likely to show an auditory AB (in the 90 ms condition). For the other stimuli, accuracy for T2 was significantly worse at Lag 3 than at Lag 9 in the 90 ms condition, suggesting the presence of an auditory AB. When AB occurred (at Lag 3), we observed smaller pupil dilations, time-locked to the onset of T2, compared to Lag 9, reflecting lower attentional processing when 'blinking' during target detection. Taken together, these findings support the conclusion that human voices escape the AB and that the pupillary changes are consistent with the so-called T2 attentional deficit. In addition, we found some indication that salient stimuli like human voices could require a less intense allocation of attention, or noradrenergic potentiation, compared to other auditory stimuli.

Electrophysiological Chronometry of Graded Consciousness during the Attentional Blink.

One of the ongoing debates about visual consciousness is whether it can be considered as an all-or-none or a graded phenomenon. While there is increasing evidence for the existence of graded states of conscious awareness based on paradigms such as visual masking, only little and mixed evidence is available for the attentional blink paradigm, specifically in regard to electrophysiological measures. Thereby, the all-or-none pattern reported in some attentional blink studies might have originated from specifics of the experimental design, suggesting the need to examine the generalizability of results. In the present event-related potential (ERP) study (N = 32), visual awareness of T2 face targets was assessed via subjective visibility ratings on a perceptual awareness scale in combination with ERPs time-locked to T2 onset (components P1, N1, N2, and P3). Furthermore, a classification task preceding visibility ratings allowed to track task performance. The behavioral results indicate a graded rather than an all-or-none pattern of visual awareness. Corresponding graded differences in the N1, N2, and P3 components were observed for the comparison of visibility levels. These findings suggest that conscious perception during the attentional blink can occur in a graded fashion.

It's time for attentional control: Temporal expectation in the attentional blink.

The attentional blink (AB) reveals a limitation in conscious processing of sequential targets. Although it is widely held that the AB derives from a structural bottleneck of central capacity, how the central processing is constrained is still unclear. As the AB reflects the dilemma of deploying attentional resources in the time dimension, research on temporal allocation provides an important avenue for understanding the mechanism. Here we reviewed studies regarding the role of temporal expectation in modulating the AB performance primarily based on two temporal processing strategies: interval-based and rhythm-based timings. We showed that both temporal expectations can help to organize limited resources among multiple attentional episodes, thereby mitigating the AB effect. As it turns out, scrutinizing on the AB from a temporal perspective is a promising way to comprehend the mechanisms behind the AB and conscious cognition. We also highlighted some unresolved issues and discussed potential directions for future research.

Perception of the temporal order of digits during rapid serial visual presentation is influenced by their ordinality.

Psychological research has extensively shown that individuals are limited in their ability to process environmental information temporally. In a rapid serial visual presentation, the ability to identify the second of two targets presented in close succession among distractors is usually impaired, a phenomenon known as attentional blink (AB). Paradoxically, when the second target immediately succeeds the first one (lag 1), such an ability is relatively spared, but individuals are more prone to misreport their correct temporal succession. Competitive mechanisms based on prior entry and perceptual integration processes have been suggested to account for the apparent loss of temporal information. We report findings from four experiments, showing that, once identified, categorical dimensions of the stimuli used as targets (here, the ordinality of numbers) may guide the perception and the resulting report of their temporal order. Specifically, at lag 1 individuals more frequently encode the two digits in ascending order. Such a biased regularization may represent another possible outcome of the failure in temporal segregation observed at lag 1, indicating that a mechanism based on prior entry is not generalizable in explaining order reversals. The kind of stimuli chosen as targets in AB paradigms can activate high-level categorical dimensions capable of influencing the performance on this task.

Impact of depression and post-traumatic stress on manual and oculomotor performance in service members with a history of mild TBI.

OBJECTIVE: To determine the impact of depression and post-traumatic stress on an automated oculomotor and manual measure of visual attention, compared to conventional neuropsychological assessment. Setting: Military traumatic brain injury (TBI) rehabilitation program. PARTICIPANTS: 188 Active Duty Service Members (ADSM) with a history of mild TBI. DESIGN: A cross-sectional and correlational study with data obtained through an IRB-approved data registry study. Main measures: Bethesda Eye & Attention Measure (BEAM); brief neuropsychological battery; self-reported symptom surveys including Neurobehavioral Symptom Inventory (NSI), Patient Health Questionnaire-8 (PHQ-8), and PTSD Checklist-5 (PCL-5). RESULTS: Small effect sizes were found for partial correlations between both depression and post-traumatic stress and key BEAM metrics. In contrast, small-to-medium effects sizes were found across all traditional neuropsychological test measures. CONCLUSION: This study illustrates the profile of impairments associated with depression and post-traumatic stress on saccadic eye movements and manual responses to BEAM relative to conventional neuropsychological tests. Results demonstrated that among ADSM seen for mTBI, depression and PTS exert a significant negative impact on measures of processing speed, attention, executive function, and memory across saccadic, manual, and conventional neuropsychological tests. However, the unique psychometric features of each of these assessment approaches may assist in distinguishing the effects of psychiatric comorbidities within this population.

Spatial distribution of emotional attentional blink under top-down attentional control.

Emotion-induced blindness (EIB) refers to the impaired perception of a neutral target that follows an emotional distractor within the time gap of 100-500 ms. Recent studies on EIB show that EIB is spatially localized. Blink occurs when both target and emotional distractor appear in the same stream but not the opposite. However, the influence of top-down attentional control over the dual-stream EIB remains poorly understood. Examining the role of top-down control in EIB will help understand the impact of attentional control over the spatial distribution of EIB and in understanding the Attentional Blink (AB) and EIB distinction. Hence, in the present study, we used dual-stream and manipulated the attentional control by changing the relevance of the emotional image and asking participants to report both emotional and neutral targets. Our results show a similar level of blink irrespective of the spatial location of the emotional T1, suggesting the role of attentional control on the spatial distribution of EIB and in the AB-EIB distinction. Results have implications for the theoretical understanding of EIB.