Competition explains limited attention and perceptual resources: implications for perceptual load and dilution theories

Brains over beauty: A preregistered test of the effects of objectification on women's cognitive performance

The present study was a preregistered, well-powered experimental test of findings related to the effect of state self-objectification and anticipation of the sexualized male gaze on women's cognitive performance. College women (n = 407) performed a working memory task in one of three randomly assigned conditions. In the experimental conditions (self-objectification and male gaze), women completed the task while being video recorded from the neck down. In the male gaze condition, participants were told their videos would later be evaluated by men as part of a separate dating study. Women in the control condition were not video recorded. Results indicated women experienced a moderate increase in state self-objectification in both experimental conditions. However, compared to the control condition, women in the experimental conditions did not show reduced performance on the working memory task (in either latency or accuracy), decreases in body satisfaction, or increases in negative mood. Across conditions, state self-objectification was not associated with accuracy or latency on the working memory task. Mixed findings concerning objectification's effect on cognitive performance may be attributed to variability in experimental manipulations and dependent variables employed in this area of research.

Semantically Adaptive JND Modeling with Object-Wise Feature Characterization, Context Inhibition and Cross-Object Interaction

Performance bottlenecks in the optimization of JND modeling based on low-level manual visual feature metrics have emerged. High-level semantics bear a considerable impact on perceptual attention and subjective video quality, yet most existing JND models do not adequately account for this impact. This indicates that there is still much room and potential for performance optimization in semantic feature-based JND models. To address this status quo, this paper investigates the response of visual attention induced by heterogeneous semantic features with an eye on three aspects, i.e., object, context, and cross-object, to further improve the efficiency of JND models. On the object side, this paper first focuses on the main semantic features that affect visual attention, including semantic sensitivity, objective area and shape, and central bias. Following that, the coupling role of heterogeneous visual features with HVS perceptual properties are analyzed and quantified. Second, based on the reciprocity of objects and contexts, the contextual complexity is measured to gauge the inhibitory effect of contexts on visual attention. Third, cross-object interactions are dissected using the principle of bias competition, and a semantic attention model is constructed in conjunction with a model of attentional competition. Finally, to build an improved transform domain JND model, a weighting factor is used by fusing the semantic attention model with the basic spatial attention model. Extensive simulation results validate that the proposed JND profile is highly consistent with HVS and highly competitive among state-of-the-art models.

Problematic Smartphone Use and Social Media Fatigue: The Mediating Role of Self-Control

Background

Excessive social media consumption leads to addiction and affects mental health. It is a phenomenon that is difficult to avoid. Previous research on the effects of excessive Internet use shows that people who engage in social media (SM) without restraint experience over-involvement, over-disclosure, technostress, and social media fatigue (SMF). SMF, conceptualized as an emotional and cognitive feeling of being overwhelmed, manifests itself in mindless browsing of content, limiting the amount of time spent on SM, or quitting SM altogether. Self-control, although present in the technology addiction literature and psychology research, has been rarely described in relation to both excessive SM use and SMF. Therefore, the main goal of the present study was to verify whether there is a direct relationship between problematic smartphone use and SMF, and whether this association is mediated by self-control.

Methods

The study included 210 respondents (M = 25.85, SD = 9.84) living in different Polish cities. The survey was conducted online, and the respondents consented to participate in the study. They completed the following measures: the Mobile Phone Problematic Use, the Self-Control Scale, the Social Media Fatigue Scale, and a brief questionnaire with socio-demographic data.

Results

Statistical analysis was performed to verify the relationship between problematic mobile phone use, level of self-control, and SMF. The outcomes indicate that there are significant interrelationships between the three studied variables. The association between problematic smartphone use and SMF is mediated by self-control.

Conclusion

A lack of impulse-inhibition skills, such as compulsive checking of notifications, can be a significant factor in SM exhaustion, fatigue, or frustration. SMF can also be understood as a natural defensive response, triggered in situations where individuals are overwhelmed, when the self-control is insufficient to stop the compulsion to use SM, and the use of a smartphone for this purpose is excessively engaging.

Functional connectivity across dorsal and ventral attention networks in response to task difficulty and experimental pain

The dorsal and ventral attention networks (DAN & VAN) provide a framework for studying attentional modulation of pain. It has been argued that cognitive demand distracts attention from painful stimuli via top-down reinforcement of task goals (DAN), whereas pain exerts an interruptive effect on cognitive performance via bottom-up pathways (VAN). The current study explores this explanatory framework by manipulating pain and task demand in combination with functional near-infrared spectroscopy (fNIRS) and Granger Causal Connectivity Analyses (GCCA). Twenty-one participants played a racing game at low and high difficulty levels with or without experimental pain (administered via a cold pressor test). Six channels of fNIRS were collected from bilateral frontal eye fields and intraparietal sulci (DAN), with right-lateralised channels at the inferior frontal gyrus and temporoparietal junction (VAN). Our first analysis revealed increased G-causality from bottom-up pathways (VAN) during the cold pressor test. However, an equivalent experience of experimental pain during gameplay increased G-causality in top-down (DAN) pathways, with the left intraparietal sulcus serving a hub of connectivity. High game difficulty increased G-causality via top-down pathways and implicated the right inferior frontal gyrus as an interhemispheric hub. Our results are discussed with reference to existing models of both networks and attentional modulation of pain.

Is perceptual learning always better at task-relevant locations? It depends on the distractors

The role of attention in task-irrelevant perceptual learning has been contested. Attention has been studied in the past using distractor-type manipulations. Hence, during an initial exposure phase, we manipulated distractor similarity within a set of six gratings, to study its effects on perceptual learning at task-relevant and task-irrelevant locations. Of these six gratings, one was at a task-relevant location, one at a task-irrelvant location, which shared the orientation with the task-relevant grating, and the rest (four) were distractor gratings. The orientations of the distractor gratings were all either the same (homogeneous) or different from each other (heterogeneity). We hypothesized that learning at the task-irrelevant location would be worse than learning at the task-relevant location when distractors are heterogeneous and vice versa when the distractors are homogeneous. Participants were initially exposed to a grating set; they reported contrast changes at only one prespecified task-relevant location. This grating was grouped based on orientation with a task-irrelevant grating presented at the furthermost distractor location and presented alongside four control-distractors (homogeneous or heterogeneous). In the testing phase, orientation discrimination performance was measured at task-relevant, task-irrelevant (grouped), and control-distractor locations. Participants were exposed and tested sequentially, each day for 5 days. Participants learned and performed better at the task-irrelevant location compared to the task-relevant location with homogenous distractors and vice versa with heterogenous distractors. The poorer learning at the task-relevant location compared to the task-irrelevant location challenges current models of perceptual learning. Selection mechanisms driven by the nature of distractors influence perceptual learning at both task-relevant and task-irrelevant locations.

Neural Coding of Visual Objects Rapidly Reconfigures to Reflect Subtrial Shifts in Attentional Focus

Every day, we respond to the dynamic world around us by choosing actions to meet our goals. Flexible neural populations are thought to support this process by adapting to prioritize task-relevant information, driving coding in specialized brain regions toward stimuli and actions that are currently most important. Accordingly, human fMRI shows that activity patterns in frontoparietal cortex contain more information about visual features when they are task-relevant. However, if this preferential coding drives momentary focus, for example, to solve each part of a task in turn, it must reconfigure more quickly than we can observe with fMRI. Here, we used multivariate pattern analysis of magnetoencephalography data to test for rapid reconfiguration of stimulus information when a new feature becomes relevant within a trial. Participants saw two displays on each trial. They attended to the shape of a first target then the color of a second, or vice versa, and reported the attended features at a choice display. We found evidence of preferential coding for the relevant features in both trial phases, even as participants shifted attention mid-trial, commensurate with fast subtrial reconfiguration. However, we only found this pattern of results when the stimulus displays contained multiple objects and not in a simpler task with the same structure. The data suggest that adaptive coding in humans can operate on a fast, subtrial timescale, suitable for supporting periods of momentary focus when complex tasks are broken down into simpler ones, but may not always do so.

The role of perceptual and cognitive load on inattentional blindness: A systematic review and three meta-analyses

The inattentional blindness phenomenon refers to situations in which a visible but unexpected stimulus remains consciously unnoticed by observers. This phenomenon is classically explained as the consequence of insufficient attention, because attentional resources are already engaged elsewhere or vary between individuals. However, this attentional-resources view is broad and often imprecise regarding the variety of attentional models, the different pools of resources that can be involved in attentional tasks, and the heterogeneity of the experimental paradigms. Our aim was to investigate whether a classic theoretical model of attention, namely the Load Theory, could account for a large range of empirical findings in this field by distinguishing the role of perceptual and cognitive resources in attentional selection and attentional capture by irrelevant stimuli. As this model has been mostly built on implicit measures of distractor interference, it is unclear whether its predictions also hold when explicit and subjective awareness of an unexpected stimulus is concerned. Therefore, we conducted a systematic review and meta-analyses of inattentional blindness studies investigating the role of perceptual and/or cognitive resources. The results reveal that, in line with the perceptual account of the Load Theory, inattentional blindness significantly increases with the perceptual load of the task. However, the cognitive account of this theory is not clearly supported by the empirical findings analysed here. Furthermore, the interaction between perceptual and cognitive load on inattentional blindness remains understudied. Theoretical implications for the Load Theory are discussed, notably regarding the difference between attentional capture and subjective awareness paradigms, and further research directions are provided.

Exploring reward-related attention selectivity deficits in Parkinson's disease

An important aspect of managing a limited cognitive resource like attention is to use the reward value of stimuli to prioritize the allocation of attention to higher-value over lower-value stimuli. Recent evidence suggests this depends on dopaminergic signaling of reward. In Parkinson's disease, both reward sensitivity and attention are impaired, but whether these deficits are directly related to one another is unknown. We tested whether Parkinson's patients use reward information when automatically allocating their attention and whether this is modulated by dopamine replacement. We compared patients, tested both ON and OFF dopamine replacement medication, to older controls using a standard attention capture task. First, participants learned the different reward values of stimuli. Then, these reward-associated stimuli were used as distractors in a visual search task. We found that patients were generally distracted by the presence of the distractors but that the degree of distraction caused by the high-value and low-value distractors was similar. Furthermore, we found no evidence to support the possibility that dopamine replacement modulates the effect of reward on automatic attention allocation. Our results suggest a possible inability in Parkinson's patients to use the reward value of stimuli when automatically allocating their attention, and raise the possibility that reward-driven allocation of resources may affect the adaptive modulation of other cognitive processes.

Nonlinear Effects of Linearly Increasing Perceptual Load on ERPs to Emotional Pictures

The prioritized processing of emotional as compared to neutral stimuli is reflected in enlarged event-related potentials (ERPs). However, perceptual load theory proposes that under conditions of high perceptual load, information processing is attenuated or abolished. The parametrical effects of load on ERPs to emotional pictures are unknown. To shed light on this question, the current preregistered ERP study (N = 30) systematically investigated the effects of load on ERPs to task-irrelevant negative, neutral, and positive pictures. Crucially, while perceptual input was held constant, perceptual load was systematically manipulated so that it increased linearly across 4 load levels, which was evident in behavioral data. In contrast, load effects on ERP differences between emotional and neutral stimuli did not follow a linear function. For the N1, early posterior negativity and late positive potential, a nonlinear function with reversed emotion effects at the third load level provided the best fit. These findings do not only show that perceptual load attenuates emotional picture processing but also suggest that active processes are initiated to reduce distraction by emotional information. Moreover, these effects of perceptual load on emotional ERP components appear to deviate from theoretically expected functions.

Top-down control of attention under varying task loads

The performance of a goal-directed task is often interrupted by task-irrelevant distractors. This distractor interference has well been demonstrated in a large body of studies employing the Eriksen flanker paradigm. A notable finding regarding this issue is that distractor interference is attenuated by increased perceptual load or the presence of non-target stimuli diluting distractors. Besides increased perceptual load or the presence of diluters, we hypothesized that either suppression of distractor or enhancement of target via top-down attentional control would also contribute to modulating distractor interference. To test this, we had participants identify a target stimulus while ignoring a distractor under three different conditions; under low load, only the target and distractor was presented, while under high load, the target was surrounded by non-target letters. In the dilution condition, the target was accompanied by non-targets, whose colors were distinct from the target. Importantly, following the task stimuli, a probe stimulus was presented either in the target location, non-target location, or distractor location. As results, under low load, attention was captured by the target stimulus in a bottom-up manner at the early stage of processing. By contrast, in the high load and dilution conditions, attention was focused on the target in a top-down manner. Taken together, we suggest that increasing perceptual load or presenting diluters incentivizes the establishment of top-down bias toward the target stimulus, which plays a role in attenuating distractor interference.

How Native Background Affects Human Performance in Real-World Visual Object Detection: An Event-Related Potential Study

Visual processing refers to the process of perceiving, analyzing, synthesizing, manipulating, transforming, and thinking of visual objects. It is modulated by both stimulus-driven and goal-directed factors and manifested in neural activities that extend from visual cortex to high-level cognitive areas. Extensive body of studies have investigated the neural mechanisms of visual object processing using synthetic or curated visual stimuli. However, synthetic or curated images generally do not accurately reflect the semantic links between objects and their backgrounds, and previous studies have not provided answers to the question of how the native background affects visual target detection. The current study bridged this gap by constructing a stimulus set of natural scenes with two levels of complexity and modulating participants' attention to actively or passively attend to the background contents. Behaviorally, the decision time was elongated when the background was complex or when the participants' attention was distracted from the detection task, and the object detection accuracy was decreased when the background was complex. The results of event-related potentials (ERP) analysis explicated the effects of scene complexity and attentional state on the brain responses in occipital and centro-parietal areas, which were suggested to be associated with varied attentional cueing and sensory evidence accumulation effects in different experimental conditions. Our results implied that efficient visual processing of real-world objects may involve a competition process between context and distractors that co-exist in the native background, and extensive attentional cues and fine-grained but semantically irrelevant scene information were perhaps detrimental to real-world object detection.

Face and emotional expression processing under continuous perceptual load tasks: An ERP study

High perceptual load is thought to impair already the early stages of visual processing of task-irrelevant visual stimuli. However, recent studies showed no effects of perceptual load on early ERPs in response to task-irrelevant emotional faces. In this preregistered EEG study (N = 40), we investigated the effects of continuous perceptual load on ERPs to fearful and neutral task-irrelevant faces and their phase-scrambled versions. Perceptual load did not modulate face or emotion effects for the P1 or N170. In contrast, larger face-scramble and fearful-neutral differentiation were found during low as compared to high load for the Early Posterior Negativity (EPN). Further, face-independent P1, but face-dependent N170 emotional modulations were observed. Taken together, our findings show that P1 and N170 face and emotional modulations are highly resistant to load manipulations, indicating a high degree of automaticity during this processing stage, whereas the EPN might represent a bottleneck in visual information processing.

Hemifield-specific control of spatial attention and working memory: Evidence from hemifield crossover costs

Attentional tracking and working memory tasks are often performed better when targets are divided evenly between the left and right visual hemifields, rather than contained within a single hemifield (Alvarez & Cavanagh, 2005; Delvenne, 2005). However, this bilateral field advantage does not provide conclusive evidence of hemifield-specific control of attention and working memory, because it can be explained solely from hemifield-limited spatial interference at early stages of visual processing. If control of attention and working memory is specific to each hemifield, maintaining target information should become more difficult as targets move between the two hemifields. Observers in the present study maintained targets that moved either within or between the left and right hemifields, using either attention (Experiment 1) or working memory (Experiment 2). Maintaining spatial information was more difficult when target items moved between the hemifields compared with when target items moved within their original hemifields, consistent with hemifield-specific control of spatial attention and working memory. However, this pattern was not found for maintaining identity information (e.g., color) in working memory (Experiment 3). Together, these results provide evidence that control of spatial attention and working memory is specific to each hemifield, and that hemifield-specific control is a unique signature of spatial processing.

Elucidating the role of selective attention, divergent thinking, language abilities, and executive functions in metaphor generation

Metaphoric language is one of the most common expressions of creative cognition in everyday life. However, the cognitive mechanisms underlying metaphor generation remain largely unexplained. In this study, we aimed to investigate the relationship between various cognitive functions and both novel and conventional metaphor generation. Ninety-five undergraduate students were administered a metaphor generation task that assesses novel and conventional metaphor generation, along with a battery of different cognitive measures: vocabulary; divergent thinking (Tel Aviv Creativity Test), working memory (WM) via digit span tests, executive functions (EFs) using the Behavioral Rating Inventory of Executive Function (BRIEF) questionnaire, and selective attention (lateralized global-local digit task). Results of a path analysis indicated that - whereas only selective attention contributed to conventional metaphor generation - selective attention, divergent thinking, and EFs contributed to novel metaphor generation beyond vocabulary and WM. Thus, the results indicate that although both novel and conventional metaphor generation are linked to attentional resources and inhibitory control, the greater creativity inherent in novel metaphor generation appears to reflect a more complex set of cognitive processes than conventional metaphor generation.

Push-pull competition between bottom-up and top-down auditory attention to natural soundscapes

In everyday social environments, demands on attentional resources dynamically shift to balance our attention to targets of interest while alerting us to important objects in our surrounds. The current study uses electroencephalography to explore how the push-pull interaction between top-down and bottom-up attention manifests itself in dynamic auditory scenes. Using natural soundscapes as distractors while subjects attend to a controlled rhythmic sound sequence, we find that salient events in background scenes significantly suppress phase-locking and gamma responses to the attended sequence, countering enhancement effects observed for attended targets. In line with a hypothesis of limited attentional resources, the modulation of neural activity by bottom-up attention is graded by degree of salience of ambient events. The study also provides insights into the interplay between endogenous and exogenous attention during natural soundscapes, with both forms of attention engaging a common fronto-parietal network at different time lags.

Cognitive Advantage in Children Enrolled in a Second-Language Immersion Elementary School Program for One Year

Early bilingualism has been shown to improve attentional and executive functioning. Nicolay and Poncelet (2013a, 2015) have shown that an early immersion program in school of 3 years improves the completion of tasks assessing these skills. This study aimed to determine whether similar benefits might be present after only 1 year of immersion education. The study also observed whether these potential advantages might also have a positive effect on the academic achievement. Participants included 59 immersed children and 57 monolingual controls. The two groups were compared using the same tasks as those employed by Nicolay and Poncelet (2015). The immersed children showed faster responses in comparison to monolinguals on the selective auditory task. No significant differences were observed on the other attentional, executive, or academic tasks. These outcomes suggest that a period of immersion education as short as 1 year can yield cognitive advantages associated with bilingualism.

Fatigue-independent alterations in muscle activation and effort perception during forearm exercise: role of local oxygen delivery

The oxygen-conforming response (OCR) of skeletal muscle refers to a downregulation of muscle force for a given muscle activation when oxygen delivery (O₂D) is reduced, which is rapidly reversed when O₂D is restored. We tested the hypothesis that the OCR exists in voluntary human exercise and results in compensatory changes in muscle activation to maintain force output, thereby altering perception of effort. In eight men and eight women, electromyography (EMG), oxyhemoglobin (O₂Hb) and deoxyhemoglobin (HHb), forearm blood flow (FBF), and task effort awareness (TEA) were measured. Participants completed two nonfatiguing rhythmic handgrip tests consisting of 5-min steady state (SS) followed by two bouts of 2-min brachial artery compression to reduce FBF by ~50% of SS (C1 and C2), separated by 2 min of no compression (NC1) and ending with 2 min of no compression (NC2). When FBF was compromised during C1, EMG/Force (1.58 ± 0.39) increased compared with SS (1.31 ± 0.33, P = 0.001). However, EMG/Force was not restored upon FBF restoration at NC1 (1.48 ± 0.38, P = 0.479), consistent with C1 evoking skeletal muscle fatigue. When FBF was compromised during C2, EMG/Force increased (1.73 ± 0.50) compared with NC1 (1.48 ± 0.38, P = 0.013). EMG/Force returned to NC1 levels during NC2 (1.50 ± 0.39, P = 0.016), consistent with an OCR in C2. TEA (SS 2.2 ± 2.3, C1 3.9 ± 2.5, NC1 3.4 ± 2.7, C2 4.6 ± 2.7, NC2 3.9 ± 2.8) mirrored changes in EMG. It is noteworthy that during the second compromise and then restoration of muscle oxygenation EMG and TEA were rapidly restored to precompromise levels. We interpreted these findings to support the existence of an OCR and its ability to rapidly modify perception of effort during voluntary exercise. NEW & NOTEWORTHY In healthy individuals, when force output is maintained during rhythmic handgrip exercise, muscle activation and perception of effort rapidly increase with compromised muscle oxygen delivery (O₂D) and then return to precompromised levels when muscle O₂D is restored. These findings suggest that an oxygen-conforming response (OCR) exists and is able to modify perception of effort during voluntary exercise. Therefore, similar to fatigue, an OCR may have implications for exercise tolerance.

The Role of Attention in Therapy for Children and Adolescents Who Stutter: Cognitive Behavioral Therapy and Mindfulness-Based Interventions

METHOD

This clinical discussion paper will explore two aspects of attention in relation to young people who stutter and their parents: (a) what we attend to as human beings and (b) how we attend. It will draw on research and clinical practice informed by CBT and MBIs. Specifically, information-processing theory in CBT explains psychological well-being partly in terms of what individuals focus their attention on, whereas MBIs focus on the relationship between how individuals attend to their internal experiences and their psychological well-being.

CONCLUSIONS

Although a nascent field, MBIs may be useful as a part of therapy for children and adolescents who stutter. The concepts highlighted by MBIs may also help to resolve some clinical issues.

Opposing effects of memory-driven and stimulus-driven attention on distractor perception

It is well known that a match between working memory contents and a visual stimulus creates attentional bias toward the memory-matching stimulus. The present study investigated whether this memory-driven attentional bias exerts similar effects with conventional, spatial attention driven by a cue stimulus. Specifically, we examined how the effect of a distracting, task-irrelevant stimulus is modulated when attention was oriented toward the distractor in memory- and stimulus-driven manners. The results showed that significant interference by a distractor decreased when attention was allocated to the distractor in a memory-driven manner, whereas the distracter captured attention in a stimulus-driven manner exerted increased interference. By contrast, memory-driven attention brought an unattended stimulus into attentional focus, while stimulus-driven attention failed to do so. These results provide evidence that the mechanisms underlying working memory-driven and stimulus-driven attention are separable, pointing to the dynamic and flexible relationship between working memory and attention.

When increasing distraction helps learning: Distractor number and content interact in their effects on memory

Previous work has demonstrated that increasing the number of distractors in a search array can reduce interference from distractor content during target processing. However, it is unclear how this reduced interference influences learning of target information. Here, we investigated how varying the amount and content of distraction present in a learning environment affects visual search and subsequent memory for target items. In two experiments, we demonstrate that the number and content of competing distractors interact in their influence on target selection and memory. Specifically, while increasing the number of distractors present in a search array made target detection more effortful, it did not impair learning and memory for target content. Instead, when the distractors contained category information that conflicted with the target, increasing the number of distractors from one to three actually benefitted learning and memory. These data suggest that increasing numbers of distractors may reduce interference from conflicting conceptual information during encoding.

Competitive interactions affect working memory performance for both simultaneous and sequential stimulus presentation

Competition between simultaneously presented visual stimuli lengthens reaction time and reduces both the BOLD response and neural firing. In contrast, conditions of sequential presentation have been assumed to be free from competition. Here we manipulated the spatial proximity of stimuli (Near versus Far conditions) to examine the effects of simultaneous and sequential competition on different measures of working memory (WM) for colour. With simultaneous presentation, the measure of WM precision was significantly lower for Near items, and participants reported the colour of the wrong item more often. These effects were preserved when the second stimulus immediately followed the first, disappeared when they were separated by 500 ms, and were partly recovered (evident for our measure of mis-binding but not WM precision) when the task was altered to encourage participants to maintain the sequentially presented items together in WM. Our results show, for the first time, that competition affects the measure of WM precision, and challenge the assumption that sequential presentation removes competition.

Age-Related Changes in the Ability to Switch between Temporal and Spatial Attention

Background: Identifying age-related changes in cognition that contribute towards reduced driving performance is important for the development of interventions to improve older adults' driving and prolong the time that they can continue to drive. While driving, one is often required to switch from attending to events changing in time, to distribute attention spatially. Although there is extensive research into both spatial attention and temporal attention and how these change with age, the literature on switching between these modalities of attention is limited within any age group. Methods: Age groups (21-30, 40-49, 50-59, 60-69 and 70+ years) were compared on their ability to switch between detecting a target in a rapid serial visual presentation (RSVP) stream and detecting a target in a visual search display. To manipulate the cost of switching, the target in the RSVP stream was either the first item in the stream (Target 1st), towards the end of the stream (Target Mid), or absent from the stream (Distractor Only). Visual search response times and accuracy were recorded. Target 1st trials behaved as no-switch trials, as attending to the remaining stream was not necessary. Target Mid and Distractor Only trials behaved as switch trials, as attending to the stream to the end was required. Results: Visual search response times (RTs) were longer on "Target Mid" and "Distractor Only" trials in comparison to "Target 1st" trials, reflecting switch-costs. Larger switch-costs were found in both the 40-49 and 60-69 years group in comparison to the 21-30 years group when switching from the Target Mid condition. Discussion: Findings warrant further exploration as to whether there are age-related changes in the ability to switch between these modalities of attention while driving. If older adults display poor performance when switching between temporal and spatial attention while driving, then the development of an intervention to preserve and improve this ability would be beneficial.

Visual search for object categories is predicted by the representational architecture of high-level visual cortex

Visual search is a ubiquitous visual behavior, and efficient search is essential for survival. Different cognitive models have explained the speed and accuracy of search based either on the dynamics of attention or on similarity of item representations. Here, we examined the extent to which performance on a visual search task can be predicted from the stable representational architecture of the visual system, independent of attentional dynamics. Participants performed a visual search task with 28 conditions reflecting different pairs of categories (e.g., searching for a face among cars, body among hammers, etc.). The time it took participants to find the target item varied as a function of category combination. In a separate group of participants, we measured the neural responses to these object categories when items were presented in isolation. Using representational similarity analysis, we then examined whether the similarity of neural responses across different subdivisions of the visual system had the requisite structure needed to predict visual search performance. Overall, we found strong brain/behavior correlations across most of the higher-level visual system, including both the ventral and dorsal pathways when considering both macroscale sectors as well as smaller mesoscale regions. These results suggest that visual search for real-world object categories is well predicted by the stable, task-independent architecture of the visual system.

NEW & NOTEWORTHY

Here, we ask which neural regions have neural response patterns that correlate with behavioral performance in a visual processing task. We found that the representational structure across all of high-level visual cortex has the requisite structure to predict behavior. Furthermore, when directly comparing different neural regions, we found that they all had highly similar category-level representational structures. These results point to a ubiquitous and uniform representational structure in high-level visual cortex underlying visual object processing.

Applied Cliplets-based half-dynamic videos as intervention learning materials to attract the attention of adolescents with autism spectrum disorder to improve their perceptions and judgments of the facial expressions and emotions of others

BACKGROUND

Autism spectrum disorders (ASD) are characterized by a reduced ability to understand the emotional expressions on other people's faces. Increasing evidence indicates that children with ASD might not recognize or understand crucial nonverbal behaviors, which likely causes them to ignore nonverbal gestures and social cues, like facial expressions, that usually aid social interaction.

OBJECTIVE

In this study, we used software technology to create half-static and dynamic video materials to teach adolescents with ASD how to become aware of six basic facial expressions observed in real situations.

METHODS

This intervention system provides a half-way point via a dynamic video of a specific element within a static-surrounding frame to strengthen the ability of the six adolescents with ASD to attract their attention on the relevant dynamic facial expressions and ignore irrelevant ones.

RESULTS

Using a multiple baseline design across participants, we found that the intervention learning system provided a simple yet effective way for adolescents with ASD to attract their attention on the nonverbal facial cues; the intervention helped them better understand and judge others' facial emotions.

CONCLUSION

We conclude that the limited amount of information with structured and specific close-up visual social cues helped the participants improve judgments of the emotional meaning of the facial expressions of others.

Intramodal Olfactory Priming of Positive and Negative Odors in Humans Using Respiration-Triggered Olfactory Stimulation (RETROS)

Priming describes the principle of modified stimulus perception that occurs due to a previously presented stimulus. Although we have begun to understand the mechanisms of crossmodal priming, the concept of intramodal olfactory priming remains relatively unexplored. Therefore, we applied positive and negative odors using respiration-triggered olfactory stimulation (RETROS), enabling us to record the skin conductance response (SCR) and breathing data without a crossmodal cueing error and measure reaction times (RTs) for olfactory tasks. RT, SCR, and breathing data revealed that negative odors were perceived significantly more arousing than positive ones. In a second experiment, 2 odors were applied during consecutive respirations. Here, we observed intramodal olfactory priming effects: A negative odor preceded by a positive odor was rated as more pleasant than when the same odor was preceded by a negative odor. Additionally, a longer identification RT was found for the second compared with the first odor. We interpret this as increased "perceptual load" due to incomplete first odor processing while the second odor was presented. Furthermore, intramodal priming can be considered a possible reason for the increase of identification RT. The use of RETROS led to these novel insights into olfactory processing beyond crossmodal interaction by providing a noncued unimodal olfactory test, and therefore, RETROS can be used in the experimental design of future olfactory studies.

Visual short-term memory load strengthens selective attention

Perceptual load theory accounts for many attentional phenomena; however, its mechanism remains elusive because it invokes underspecified attentional resources. Recent dual-task evidence has revealed that a concurrent visual short-term memory (VSTM) load slows visual search and reduces contrast sensitivity, but it is unknown whether a VSTM load also constricts attention in a canonical perceptual load task. If attentional selection draws upon VSTM resources, then distraction effects-which measure attentional "spill-over"-will be reduced as competition for resources increases. Observers performed a low perceptual load flanker task during the delay period of a VSTM change detection task. We observed a reduction of the flanker effect in the perceptual load task as a function of increasing concurrent VSTM load. These findings were not due to perceptual-level interactions between the physical displays of the two tasks. Our findings suggest that perceptual representations of distractor stimuli compete with the maintenance of visual representations held in memory. We conclude that access to VSTM determines the degree of attentional selectivity; when VSTM is not completely taxed, it is more likely for task-irrelevant items to be consolidated and, consequently, affect responses. The "resources" hypothesized by load theory are at least partly mnemonic in nature, due to the strong correspondence they share with VSTM capacity.

Enhanced visual dominance in far space

The Colavita effect refers to the phenomenon that people do not respond to an auditory stimulus in most cases when a visual stimulus is simultaneously presented. Although the Colavita effect remains robust irrespective of many factors, little is known concerning how the visual dominance varies as a function of the depth of sensory inputs. In the present study, visual and auditory stimuli were presented either in the same (in Experiment 1) or in the different spatial distances (in Experiment 2). Participants were asked to make speeded responses to unimodal auditory, unimodal visual, or bimodal audiovisual stimuli. In the incorrectly responded bimodal trials, the error trials in which responses were made only to the visual component were compared with the trials in which responses were made only to the auditory component. In the correctly responded bimodal trials, the trials in which participants responded first to the visual component were compared with the trials in which participants responded first to the auditory component. Analysis on the incorrect and correct bimodal trials both indicated significant visual dominance effects. More importantly, the size of the visual dominance effect was significantly enhanced as long as the visual stimuli were presented in far space irrespective of whether the auditory stimuli were presented in near or far space. Our results thus, for the first time, revealed that the visual dominance effect changed along the depth dimension of space. Taken together, the present results shed lights on how the allocation of attentional resources along the depth dimension of space biases the process of multisensory competition.

Processing multiple visual objects is limited by overlap in neural channels

High-level visual categories (e.g., faces, bodies, scenes, and objects) have separable neural representations across the visual cortex. Here, we show that this division of neural resources affects the ability to simultaneously process multiple items. In a behavioral task, we found that performance was superior when items were drawn from different categories (e.g., two faces/two scenes) compared to when items were drawn from one category (e.g., four faces). The magnitude of this mixed-category benefit depended on which stimulus categories were paired together (e.g., faces and scenes showed a greater behavioral benefit than objects and scenes). Using functional neuroimaging (i.e., functional MRI), we showed that the size of the mixed-category benefit was predicted by the amount of separation between neural response patterns, particularly within occipitotemporal cortex. These results suggest that the ability to process multiple items at once is limited by the extent to which those items are represented by separate neural populations.

Accurate expectancies diminish perceptual distraction during visual search

The load theory of visual attention proposes that efficient selective perceptual processing of task-relevant information during search is determined automatically by the perceptual demands of the display. If the perceptual demands required to process task-relevant information are not enough to consume all available capacity, then the remaining capacity automatically and exhaustively “spills-over” to task-irrelevant information. The spill-over of perceptual processing capacity increases the likelihood that task-irrelevant information will impair performance. In two visual search experiments, we tested the automaticity of the allocation of perceptual processing resources by measuring the extent to which the processing of task-irrelevant distracting stimuli was modulated by both perceptual load and top-down expectations using behavior, functional magnetic resonance imaging, and electrophysiology. Expectations were generated using a trial-by-trial cue that provided information about the likely load of the upcoming visual search task. When the cues were valid, behavioral interference was eliminated and the influence of load on frontoparietal and visual cortical responses was attenuated relative to when the cues were invalid. In conditions in which task-irrelevant information interfered with performance and modulated visual activity, individual differences in mean blood oxygenation level dependent responses measured from the left intraparietal sulcus were negatively correlated with individual differences in the severity of distraction. These results are consistent with the interpretation that a top-down biasing mechanism interacts with perceptual load to support filtering of task-irrelevant information.

A new perspective on the perceptual selectivity of attention under load

The human attention system helps us cope with a complex environment by supporting the selective processing of information relevant to our current goals. Understanding the perceptual, cognitive, and neural mechanisms that mediate selective attention is a core issue in cognitive neuroscience. One prominent model of selective attention, known as load theory, offers an account of how task demands determine when information is selected and an account of the efficiency of the selection process. However, load theory has several critical weaknesses that suggest that it is time for a new perspective. Here we review the strengths and weaknesses of load theory and offer an alternative biologically plausible computational account that is based on the neural theory of visual attention. We argue that this new perspective provides a detailed computational account of how bottom-up and top-down information is integrated to provide efficient attentional selection and allocation of perceptual processing resources.

Intrinsic fluctuations in sustained attention and distractor processing

Although sustaining a moderate level of attention is critical in daily life, evidence suggests that attention is not deployed consistently, but rather fluctuates from moment to moment between optimal and suboptimal states. To better characterize these states in humans, the present study uses a gradual-onset continuous performance task with irrelevant background distractors to explore the relationship among behavioral fluctuations, brain activity, and, in particular, the processing of visual distractors. Using fMRI, we found that reaction time variability, a continuous measure of attentional instability, was positively correlated with activity in task-positive networks and negatively correlated with activity in the task-negative default mode network. We also observed greater processing of distractor images during more stable and less error prone "in the zone" epochs compared with suboptimal "out of the zone" epochs of the task. Overall, the data suggest that optimal states of attention are accomplished with more efficient and potentially less effortful recruitment of task-relevant resources, freeing remaining resources to process task irrelevant features of the environment.

Top-down processing modulates older adults' susceptibility to noise

The present study examined older and younger adults' ability to use top-down processes to mitigate the effects of display noise during simple feature, visual search. As display noise levels increased, older adults (age 60-74 years, n = 32) exhibited greater top-down search reaction time (RT) benefits (bottom-up minus top-down search RT), compared to younger adults (age 18-27, n = 32). Older adults' ability to mitigate the effects of noise was further assessed with RT variability, as measured by intra-individual standard deviations across trials. Older adults again exhibited larger top-down benefits (i.e., less RT variability) compared to younger adults, and more so when display noise was present vs. absent. These results suggest a sparing of top-down processes with age (Madden, Whiting, Spaniol, & Bucur, 2005; Psychology and Aging, 20, 317), and that top-down processes in older adults enhance search efficiency by optimizing signal-to-noise ratios.