Perceptual Load Theory Research Articles

Does presentation size of instructional materials influence the split‐attention effect?

AbstractThe split‐attention effect posits that learning outcomes are negatively impacted when interrelated text and graphics are spatially segregated rather than cohesively integrated. This study explored how the instructional material's presentation size influences the manifestation of the split‐attention effect. Based on cognitive load theory and perceptual load theory, we hypothesized that elevated information density in a compact presentation format would attenuate the advantage of integrated text and graphics, thereby diminishing the salience of the split‐attention effect relative to a more expansive presentation size. University students (n = 146) studied a split‐attention format or integrated format in either large or small presentation size. Results on retention and comprehension tests and extraneous cognitive load ratings revealed no effects of instructional format, presentation size or their interaction. The present results call for a more nuanced understanding of the split‐attention effect and suggest additional research to explore its cognitive foundations.

Cue Predictability Modulates the Perceptual Load's Attentional Control on Threatening Facial Distractors

Background: According to the perceptual load theory, distractor processing is determined by the perceptual load. Alternatively, some explanations suggest that perceptual load and distractor salience may have opposing effects. Objectives: Although numerous studies have been conducted on the effect of distractor salience on attentional capture, even under conditions of high perceptual load, it is still unclear whether spatial cueing of the distractor interferes with the perceptual load. Methods: In two experiments, the effect of the predictability of distractor cueing on attentional capture due to threatening facial stimuli was studied using a modified flanker task. In experiment 2, unlike the first experiment, heterogeneous targets and distractors were used to mimic real-life experiences. Results: In experiment 1, the high perceptual load was associated with decreased distractor processing, whether the cueing was completely valid, invalid, or absent. However, the distractor processing between low and high perceptual loads was not different in ambiguous cueing. In the second experiment, contrary to the first experiment, no perceptual load effect was observed in the absence of spatial cueing. Conclusions: Even in displays with high perceptual load, some stimulus-driven features-inability to predict the distractor's location—can interfere with attentional control. Therefore, although the perceptual load is an influential factor in the selection, it clearly cannot be the only factor determining attentional control. Additionally, this study reveals that the effect of perceptual load on attentional control in everyday life should be further studied and questioned.

Banner blindness as the suppression process: No perceptual load effect on web advertising detection

ABSTRACTThe study represents an application of perceptual load theory to the real-world internet users’ behavior and contributes to the dispute whether banner blindness – a tendency to ignore the banners on web pages – is a special case of inattentional blindness or a separate phenomenon. Perceptual load theory claims that processing of task-irrelevant information can be predicted by the level of perceptual load: the subjects in a high load condition are more likely to ignore the distractors, while with a low load, task-irrelevant information is processed. In four experiments, participants were divided into low and high load groups and asked to find items on a shopping website. In the critical trial, an advertising banner appeared. No significant effect of perceptual load on banner blindness was found. Banner blindness seems to be a result of attentional filters adjustment that adapts to the abundance of information on the web pages.

An Exploration of the Effects of Cross-Modal Tasks on Selective Attention.

Successful performance of a task relies on selectively attending to the target, while ignoring distractions. Studies on perceptual load theory (PLT), conducted involving independent tasks with visual and auditory modalities, have shown that if a task is low-load, distractors and the target are both processed. If the task is high-load, distractions are not processed. The current study expands these findings by considering the effect of cross-modality (target and distractor from separate modalities) and congruency (similarity of target and distractor) on selective attention, using a word-identification task. Parameters were analysed, including response time, accuracy rates, congruency of distractions, and subjective report of load. In contrast to past studies on PLT, the results of the current study show that modality (congruency of the distractors) had a significant effect and load had no effect on selective attention. This study demonstrates that subjective measurement of load is important when studying perceptual load and selective attention.

The Hybrid Model of Attentional Selection: Perceptual Load

It is a crucial cognitive skill to select the relevant ones and exclude the irrelevant ones from all the stimuli we are exposed to in our constantly changing visual environment. While the long-standing early-late selection debates on the efficient attentional selection are still relevant, a hybrid theory was proposed by Lavie and Tsal (1994). Perceptual load theory is similar to the early selection approach in that it emphasizes limited capacity, while it is similar to late selection approaches in that it emphasizes automatic processing. In line with the theory, distractor processing depends on the task-relevant perceptual load. As perceptual load increases, unrelated stimuli can easily be excluded from the attention filter; because the capacity is full. The distractor interference effect is inevitable if the perceptual load is not high enough to fill the restricted capacity. According to the theory, the perceptual load is a key factor of the locus of selection. Although many support studies have been carried out after the theory was supposed, the number of studies inconsistent with the theory's assumptions, especially in recent years, cannot be ignored. Diverse studies have shown the importance of other factors in selective attention, such as salience, proximity, similarity, and dilution effect. In conclusion, despite being an important factor, the perceptual load is not the primary determinant in efficient attentional selection.

Alpha oscillations reflect suppression of distractors with increased perceptual load.

Attention serves an essential role in cognition and behavior allowing us to focus on behaviorally-relevant objects while ignoring distraction. Perceptual load theory states that attentional resources are allocated according to the requirements of the task, i.e., its 'load'. The theory predicts that the resources left to process irrelevant, possibly distracting stimuli, are reduced when the perceptual load is high. However, it remains unclear how this allocation of attentional resources specifically relates to neural excitability and suppression mechanisms. In this magnetoencephalography (MEG) study, we show that brain oscillations in the alpha band (8-13Hz) implemented the suppression of distracting objects when the perceptual load was high. In parallel, high load increased the neuronal excitability for target objects, as reflected by rapid invisible frequency tagging. We suggest that the allocation of resources in tasks with high perceptual load is implemented by a gain increase for targets, complemented by distractor suppression reflected by alpha-band oscillations closing the 'gate' for interference.

Attentional Capture From Inside vs. Outside the Attentional Focus.

In this study, we jointly reported in an empirical and a theoretical way, for the first time, two main theories: Lavie’s perceptual load theory and Gaspelin et al.’s attentional dwelling hypothesis. These theories explain in different ways the modulation of the perceptual load/task difficulty over attentional capture by irrelevant distractors and lead to the observation of the opposite results with similar manipulations. We hypothesized that these opposite results may critically depend on the distractor type used by the two experimental procedures (i.e., distractors inside vs. outside the attentional focus, which could be, respectively, considered as potentially relevant vs. completely irrelevant to the main task). Across a series of experiments, we compared both theories within the same paradigm by manipulating both the perceptual load/task difficulty and the distractor type. The results were strongly consistent, suggesting that the influence of task demands on attentional capture varies as a function of the distractor type: while the interference from (relevant) distractors presented inside the attentional focus was consistently higher for high vs. low load conditions, there was no modulation by (irrelevant) distractors presented outside the attentional focus. Moreover, we critically analyzed the theoretical conceptualization of interference using both theories, disentangling important outcomes for the dwelling hypothesis. Our results provide specific insights into new aspects of attentional capture, which can critically redefine these two predominant theories.

Visual Search in 3D: Effects of Monoscopic and Stereoscopic Cues to Depth on the Validity of Feature Integration Theory and Perceptual Load Theory.

Previous research has successfully used feature integration theory to operationalise the predictions of Perceptual Load Theory, while simultaneously testing the predictions of both models. Building on this work, we test the extent to which these models hold up in a 3D world. In two experiments, participants responded to a target stimulus within an array of shapes whose apparent depth was manipulated using a combination of monoscopic and stereoscopic cues. The search task was designed to test the predictions of (a) feature integration theory, as the target was identified by a single feature or a conjunction of features and embedded in search arrays of varying size, and (b) perceptual load theory, as the task included congruent and incongruent distractors presented alongside search tasks imposing high or low perceptual load. Findings from both experiments upheld the predictions of feature integration theory, regardless of 2D/3D condition. Longer search times in conditions with a combination of monoscopic and stereoscopic depth cues suggests that binding features into three-dimensional objects requires greater attentional effort. This additional effort should have implications for perceptual load theory, yet our findings did not uphold its predictions; the effect of incongruent distractors did not differ between conjunction search trials (conceptualised as high perceptual load) and feature search trials (low perceptual load). Individual differences in susceptibility to the effects of perceptual load were evident and likely explain the absence of load effects. Overall, our findings suggest that feature integration theory may be useful for predicting attentional performance in a 3D world.

Neural and behavioral effects of perceptual load on auditory selective attention

Healthy adults performed an auditory version of the flanker task under low versus high perceptual load while behavioral and electrophysiological measures were recorded. Participants experienced less attentional interference under low load than high load, whether analyses were performed between tasks (Garner interference; found in accuracy and RT), between stimuli (flanker congruity; found in accuracy), or between sequences (Gratton effect; found in accuracy). Analysis of event-related potentials to the distractor (flanker), which was physically identical across load conditions, revealed load modulation of tasks effects in the P1 component (peak amplitude and latency), an early perceptual component peaking approximately 75 ms after distractor onset. As in behavioral performance, ERP analyses showed that auditory attentional disruption in P1 was significantly smaller under low perceptual load. Dipole source analysis suggested activation of prefrontal inhibitory control during low load and default mode network during high load. The results are in keeping with the predictions of tectonic theory (Melara & Algom, 2003), but inconsistent with expectations derived from perceptual load theory (Lavie, 1995).

In pursuit of visual attention: SSVEP frequency-tagging moving targets

Previous research has shown that visual attention does not always exactly follow gaze direction, leading to the concepts of overt and covert attention. However, it is not yet clear how such covert shifts of visual attention to peripheral regions impact the processing of the targets we directly foveate as they move in our visual field. The current study utilised the co-registration of eye-position and EEG recordings while participants tracked moving targets that were embedded with a 30 Hz frequency tag in a Steady State Visually Evoked Potentials (SSVEP) paradigm. When the task required attention to be divided between the moving target (overt attention) and a peripheral region where a second target might appear (covert attention), the SSVEPs elicited by the tracked target at the 30 Hz frequency band were significantly, but transiently, lower than when participants did not have to covertly monitor for a second target. Our findings suggest that neural responses of overt attention are only briefly reduced when attention is divided between covert and overt areas. This neural evidence is in line with theoretical accounts describing attention as a pool of finite resources, such as the perceptual load theory. Altogether, these results have practical implications for many real-world situations where covert shifts of attention may discretely reduce visual processing of objects even when they are directly being tracked with the eyes.

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.

The Perceptual Load Effect On Target Detection In Banner Blindness

Perceptual load theory claims that the processing of task-irrelevant information can be predicted by the level of perceptual load. If a particular task places a high demand on attention, the task-irrelevant stimuli processing can be prevented. That means that in high load condition the subjects are more likely to ignore distractors, while in low load task-relevant and task-irrelevant information is processed simultaneously. Though several studies showed that perceptual load can play a crucial role in inattentional blindness phenomenon, there is a lack of applied researches conducted on real-life tasks. Current study aimed implement load theory to a real-life task and to describe the effect it has on banner blindness, that has common grounds with inattentional blindness. Banner blindness is a phenomenon in usability studies which shows that subjects do not notice banners on the webpage despite their saliency. The study represents an important application of load theory to real-world behavior of Internet users. Participants were divided into low-load and high-load groups (that differed in number of presented stimuli) and asked go online shopping. At the critical trail, a banner appeared. The subjects under high load condition were expected to notice the banner less often, then under low load. The hypothesis was not supported. However, a tendency towards more reports about the banner’s presence can be seen in the low load group. We assume that if there are enough people who noticed the banner, we will be able to detect the effect of cognitive load on banner blindness.

A fad or the future? Examining the effectiveness of virtual reality advertising in the hotel industry

Abstract New virtual reality technology presents hotels with wide-ranging marketing, training, and customer service opportunities. The purpose of this study was to explore both the immediate and delayed effects of hotel VR commercials as compared to traditional video commercials. Based on the perceptual load theory and elaboration likelihood model, this study designed and conducted a 2 × 2 laboratory experiment with two stages of data collection. The study demonstrated that VR commercials produced better immediate effects than the traditional commercials, especially for participants with high elaboration likelihood levels. However, the findings also revealed significant decreases in purchase intention among participants watching VR commercials and a significant improvement in attitudes among participants watching traditional commercials. Both theoretical and practical implications were discussed to leverage the power of VR in marketing.

Tired and lack focus? Insomnia increases distractibility.

Chronic insomnia is associated with subjective daytime cognitive dysfunction, but objective corroborative data are often lacking. In this study, we use Perceptual Load Theory to objectively assess distractibility in participants with insomnia (N = 23) compared with age- and sex-matched controls (N = 23). Following overnight supervised sleep observation, all participants completed a selective attention task which varied in the level of perceptual load and distractor congruency. The insomnia group was found to be more distracted than controls, whereas their selective attention mechanism appeared to be intact, with reduced distractor processing under high load for both groups. Insomnia symptom severity was positively correlated with participant distractibility. These findings suggest that there are insomnia-related daytime cognitive impairments that are likely to arise from compromised cognitive control rather than an ineffective selective attention mechanism. This task may be clinically useful in assessing daytime impairments, and potentially treatment response, in those with insomnia.

Flanker tasks based on congruency manipulation are biased measures of selective attention in perceptual load studies.

Flanker tasks based on a flanker-target congruency manipulation are widely used in perceptual load studies to investigate under what circumstances task-irrelevant flankers may be processed. An implicit assumption underlying the congruency manipulation is that the three types of flankers (congruent, incongruent, and neutral) attract attention homogeneously. However, in the present study, we provide evidence to demonstrate that this assumption is wrong: We discovered that incongruent/congruent flankers attracted more attention than the neutral flanker did. To avoid this attentional bias induced by the flanker-target congruency manipulation, we developed a new flanker paradigm in which the extent of flanker processing was evaluated by comparing the threshold stimulus exposure durations (TSEDs) for successfully performing a target identification task when a task-irrelevant flanker was presented versus when the flanker was absent. The flanker was processed if the TSED was longer when the flanker was present than when it was absent. This new paradigm provides an unbiased measure of selective attention when neutral flankers are used. The present data, obtained with neutral flankers in the new paradigm, were consistent with the dilution theory of selective attention, but inconsistent with the perceptual load theory of selective attention.

Pupil size and search performance in low and high perceptual load

The ability to focus on a task while disregarding irrelevant information is an example of selective attention. The perceptual-load hypothesis argues that the occurrence of early or late selection mechanisms is determined by task-relevant perceptual load. Additionally, evidence shows that pupil size serves as proxy of locus coeruleus-norepinephrine (LC-NE) activity, a system associated with cognitive and attentional mediation. Here, we assessed pupil baseline (and pupil dilation) as predictors of load-related early and late selection performance. Participants were asked to search for a target in conditions of high and low perceptual load, while ignoring irrelevant stimuli. The results showed that pupil baseline size, measured prior trial onset, significantly predicted the upcoming search efficiency only in low perceptual load, when—according to the perceptual-load hypothesis—all perceptual information receives attentional resources. In addition, pupil dilation was linked to the time course of perceptual processing and predicted response times in both perceptual load conditions, an association that was enhanced in high load. Thus, this study relates attentional selection mechanisms, as defined by the perceptual-load theory, with pupil-related LC-NE activity. Because pupil baseline predicted attentional performance in low load but not in high load, this suggests that different attentional mechanisms are involved, one in which the LC-NE system plays a key role (low load) and one in which it is less relevant (high load). This suggests that the degree with which LC-NE influences behavioral performance is related to the perceptual load of the task at hand.

Opening the window: Size of the attentional window dominates perceptual load and familiarity in visual selection.

Perceptual load theory (Lavie, 1995) claims that visual selection is determined both by the perceptual demands a display imposes and by the perceptual resources an observer has available for processing. This theory is often tested by examining distractor interference in modified flanker tasks, which separate potential target locations from distractor locations and allow researchers to measure distractor processing. Although this task has provided significant insight into cognitive processing, it may also be an example of how a given task obscures potentially important experimental factors. Specifically, the structure of the target array could encourage observers to adopt a narrow attentional window, which could eliminate distractor interference as significant distractor processing has been shown to occur inside but not outside the attentional window (Belopolsky, Zwaan, Theeuwes, & Kramer, 2007). The present experiments included conditions that allowed the target to vary among the same locations as within a structured target array but varied possible nontarget locations that never overlapped with possible target locations. Whenever nontarget items remained in fixed locations, significant distractor processing occurred due to the observer adopting a wide attentional window even under high perceptual load conditions (Experiment 1). Further evidence showed that familiarity with these locations could not explain the interference (Experiment 2A). However, imposing a ring around the target array, similar to what a circular target array might impose, narrowed the attentional window and eliminated distractor interference (Experiment 2B). Thus, the size of the attentional window is capable of dominating both perceptual load and familiarity in visual selection. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Processing overlap-dependent distractor dilution rather than perceptual target load determines attentional selectivity.

The perceptual load theory of attentional selection argues that the degree to which distractors interfere with target processing is determined by the "perceptual load" (or discrimination difficulty) of target processing: when perceptual load is low, distractors interfere to a greater extent than when it is high. A well-known exception is load-independent interference effects from face distractors during processing of name targets. This finding was reconciled with load theory by proposing distinct processing resources for faces versus names. In the present study, we revisit this effect to test (a) whether increasing the processing overlap (perceptual, lexical, conceptual) between potential targets and distractors would reinstate the classic load effect, and (b) whether this data pattern could be better explained by load theory or by a rival account that argues that distractor dilution rather than target load determines the degree of distractor interference. Over four experiments, we first replicate the original finding and then show that load effects grow with increasing processing overlap between potential targets and distractors. However, by adding dilution conditions, we also show that these processing overlap dependent modulations of distractor interference can be explained by the distractor dilution perspective but not by perceptual load theory. Thus, our findings support a processing overlap dilution account of attentional selection.

面孔表情及注视方向对面孔加工特异性的影响——基于知觉负荷理论的视角 <sup>*</sup>

面孔表情及注视方向对面孔加工特异性的影响——基于知觉负荷理论的视角 <sup>*</sup>

The influence of schizotypal traits on attention under high perceptual load

Schizophrenia Spectrum Disorders (SSD) are known to be characterised by abnormalities in attentional processes, but there are inconsistencies in the literature that remain unresolved. This article considers whether perceptual resource limitations play a role in moderating attentional abnormalities in SSD. According to perceptual load theory, perceptual resource limitations can lead to attenuated or superior performance on dual-task paradigms depending on whether participants are required to process, or attempt to ignore, secondary stimuli. If SSD is associated with perceptual resource limitations, and if it represents the extreme end of an otherwise normally distributed neuropsychological phenotype, schizotypal traits in the general population should lead to disproportionate performance costs on dual-task paradigms as a function of the perceptual task demands. To test this prediction, schizotypal traits were quantified via the Schizotypal Personality Questionnaire (SPQ) in 74 healthy volunteers, who also completed a dual-task signal detection paradigm that required participants to detect central and peripheral stimuli across conditions that varied in the overall number of stimuli presented. The results confirmed decreasing performance as the perceptual load of the task increased. More importantly, significant correlations between SPQ scores and task performance confirmed that increased schizotypal traits, particularly in the cognitive-perceptual domain, are associated with greater performance decrements under increasing perceptual load. These results confirm that attentional difficulties associated with SSD extend sub-clinically into the general population and suggest that cognitive-perceptual schizotypal traits may represent a risk factor for difficulties in the regulation of attention under increasing perceptual load.