Object-based Attention Effects Research Articles

Faces do not guide attention in an object-based facilitation manner.

Numerous studies on face processing have revealed their special ability to affect attention, but relatively little research has been done on how faces guide spatial attention allocation. To enrich this field, this study resorted to the object-based attention (OBA) effect in a modified double-rectangle paradigm where the rectangles were replaced with human faces and mosaic patterns (non-face objects). Experiment 1 replicated the typical OBA effect in the non-face objects, but this effect was absent in Asian and Caucasian faces. Experiment 2 removed the eye region from Asian faces, but still found no object-based facilitation in the faces without eyes. In Experiment 3, the OBA effect was also observed for faces when the faces disappear a short period before the responses. Overall, these results revealed that when two faces are presented together, they do not exert object-based facilitation regardless of their facial features such as race and the presence of eyes. We argue that the lack of a typical OBA effect is due to the filtering cost induced by the entire face content. This cost slows down the response when attention shifts within a face and results in the absence of object-based facilitation.

Deficiency of object-based attention specific to the gaze cue is independent of top-down attentional strategies.

This study investigated whether modes of attentional selection (location-based or object-based) are modulated by the cue type, specifically social cues such as eye gaze and pointing fingers, or by a non-social cue, such as an arrow. Earlier studies have demonstrated that the object-based attention effect was found only with arrow cues when presenting a spatial cue at either end of a rectangle: gaze cues did not yield object-based facilitation. We examined whether this deficiency of object-based attention is generalized to social cues such as pointing fingers. We measured the reaction times to the target at each cued location, an opposite side of a cued location in the same object, or the location in a different object equidistant from the cued location for each cue. Results indicated that only the gaze cue weakened the object-based attention effect, even under the condition of participants' voluntary extension of their attentional focus. The pointing cue induced sufficient object-based facilitation, as did the arrow cue. These results suggest that the deficiency of object-based attention was observed only for the gaze cue, and that it would be caused by a factor that is unique to the gaze cue, which narrows the attentional focus.

Can faces affect object-based attention? Evidence from online experiments

This study tested how human faces affect object-based attention (OBA) through two online experiments in a modified double-rectangle paradigm. The results of Experiment 1 revealed that faces did not elicit the OBA effect as non-face objects, which was caused by a longer response time (RT) when attention is focused on faces relative to non-face objects. In addition, by observing faster RTs when attention was engaged horizontally rather than vertically, we found a significant horizontal attention bias, which might override the OBA effect if vertical rectangles were the only items presented; these results were replicated in Experiment 2 (using only vertical rectangles) after directly measuring horizontal bias and excluding its influence on the OBA effect. This study suggested that faces cannot elicit the same-object advantage in the double-rectangle paradigm and provided a method to measure the OBA effect free from horizontal bias.

Excess success in articles on object-based attention

Twenty-five years of research has explored the object-based attention effect using the two-rectangles paradigm and closely related paradigms. While reading this literature, we noticed statistical attributes that are sometimes related to questionable research practices, which can undermine the reported conclusions. To quantify these attributes, we applied the Test for Excess Success (TES) individually to 37 articles that investigate various properties of object-based attention and comprise four or more experiments. A TES analysis estimates the probability that a direct replication of the experiments in a given article with the same sample sizes would have the same success (or better) as the original article. If the probability is low, then readers should be skeptical about the conclusions that are based on those experimental results. We find that 19 of the 37 analyzed articles (51%) seem too good to be true in that they have a replication probability below 0.1. In a new large sample study, we do find evidence for the basic object-based attention effect in the two-rectangles paradigm, which this literature builds on. A power analysis using this data shows that commonly used sample sizes in studies that investigate properties of object-based attention with the two-rectangles paradigm are, in fact, much too small to reliably detect even the basic effect.

The role of object representation strength in the object-based attention of dynamic object

<p id=C6>According to object-based attention (OBA) theory, attention processes object as a unit. When attention is directed to a certain part of an object, the processing of other features of the object will be promoted. Object-based attention has been confirmed by many studies. However, most of the previous studies are based on static objects, and there are few studies on how object-based attention changes for dynamic objects. However, information in the real world is always changing, using dynamic objects for OBA research is more ecologically valid and necessary. For the attentional allocation of dynamic objects, there are two theoretical assumptions: the cued object hypothesis and the dynamic updating hypothesis. The cued object hypothesis proposes that object-based attention follows the original cued object, while the dynamic updating hypothesis assumes that object-based attention is determined by the changed object. The study of attention on dynamic objects also found the instantaneous object effect, which means the object-based attention follows the instantaneous object. We propose that experiments supporting the two theoretical hypotheses have differences in the experimental manipulation, which lead to changes in the relative strength between object representations of the cued object and the instantaneous object, resulting in the two seemingly contradictory points of view. As to whether attention is based on the cued object or the instantaneous object, we proposes that the relative strength between object representations of the cued and instantaneous objects plays a critical role. That is, when the cued object representation is stronger than the instantaneous object representation, the object-based attention follows the original cued object, vice versa. The concept of object representation strength is of great significance in OBA research. It is found that object representation strength can affect OBA, and stronger object representation can capture attention more easily. The factors that affect the object representation strength, such as the object presentation time, the factors that affect the surface consistency of an object (such as the object color, texture, continuous contour, etc.) and the top-down factors, will also indirectly affect OBA through affecting the object representation strength. For these reasons, introduces the concept of object representation strength to the discussion of the theory of attending dynamic objects is necessary, but previous studies did not pay attention to the effects of the object representation strength on dynamic objects. In this paper, we introduced the concept of relative object representation strength and analyze the attention theory based on dynamic objects and its experimental basis. This approach can further improve the attention theory based on dynamic objects, get a unified explanation for previous contradictory results, and explain the cause of the cued and instantaneous object effects from a new perspective. The concept of the relative strength of object representation may be critical for understanding how object-based attention is allocated under the circumstance of processing dynamic objects and resolving the conflict of related theories. At present, the research of attention based on dynamic objects mainly focuses on the determination of cued and instantaneous objects, ignoring the important role of relative object representation strength, and most of the results are compared by the reaction time. Further study could focus on the relative object representation strength to test the influence of the relative object representation strength on dynamic object-based attention and explore its underlying mechanisms. At the same time, since the OBA effect is small descriptively, the method of recording the reaction time may lead to replication issue for some results. More sensitive psychophysical methods can be used in future studies to obtain more stable and repeatable results and help to better clarify the mechanisms of the dynamic object theory.

The Normalization Model Captures the Effects of Object-based Attention in the Human Visual Cortex

Here, we report that normalization model can capture the effects of object-based attention across the visual hierarchy in the human brain. We used superimposed pairs of objects and asked participants to attend to different targets. Modeling voxel responses, we demonstrated that the normalization model outperforms other models in predicting voxel responses in the presence of attention. Our results propose normalization as a canonical computation operating in the primate brain.

Object-based selection in visual working memory

Attentional mechanisms in perception can operate over locations, features, or objects. However, people direct attention not only towards information in the external world, but also to information maintained in working memory. To what extent do perception and memory draw on similar selection properties? Here we examined whether principles of object-based attention can also hold true in visual working memory. Experiment 1 examined whether object structure guides selection independently of spatial distance. In a memory updating task, participants encoded two rectangular bars with colored ends before updating two colors during maintenance. Memory updates were faster for two equidistant colors on the same object than on different objects. Experiment 2 examined whether selection of a single object feature spreads to other features within the same object. Participants memorized two sequentially presented Gabors, and a retro-cue indicated which object and feature dimension (color or orientation) would be most relevant to the memory test. We found stronger effects of object selection than feature selection: accuracy was higher for the uncued feature in the same object than the cued feature in the other object. Together these findings demonstrate effects of object-based attention on visual working memory, at least when object-based representations are encouraged, and suggest shared attentional mechanisms across perception and memory.

Attention can operate on object representations in visual sensory memory.

Numerous studies have shown that attention can be allocated to various types of objects, such as low-level objects developed by perceptual organization and high-level objects developed by semantic associations. However, little is known about whether attention can also be affected solely by object representations in the brain, after the disappearance of physical objects. Here, we used a modified double-rectangle paradigm to investigate how attention is affected by object representation in visual sensory memory when the physical objects disappear for a short period of time before the target onset. By manipulating the interstimulus interval (ISI) between the offset of the objects and the onset of the target, an object-based attention effect, with shorter reaction times (RTs) for within-object relative to between-object conditions, was observed in the short-ISI (within 500 ms in Experiments 1a, 1b, 2, and 3) conditions while disappearing in the long-ISI (800 ms in Experiment 4) conditions. This result demonstrated that the mere presence of object representation in visual sensory memory, or the sensory memory-maintained object, can serve as an object unit that attention can operate on. This provides evidence for the relationship between object-based attention and visual sensory memory: object representation in visual sensory memory could affect attentional allocation, or attention can operate on a sensory memory-maintained object.

Same-object costs and benefits in the object-based attentional blink

Object-based attention (OBA) studies using the double-rectangle paradigm have revealed same-object costs with vertical rectangles but same-object benefits with horizontal rectangles, showing asymmetry in the OBA effect. Attentional blink (AB) studies using rapid serial visual presentation (RSVP) paradigms have shown that when two targets (T1 and T2) are successively presented within 400 msec, T2 performance is significantly impaired (i.e., an AB effect). Some object-based AB studies have indicated that the stable representation of single objects before T1 reduced the same-object AB effect, and some have claimed that the inhibition of the global objects representation by T1 processing enhanced the same-object AB effect. However, these studies did not directly explore whether and how the object representation modulated the object-based AB effect. In the present study, we used a hybrid of the RSVP and double-rectangle paradigms to address this issue. The results revealed that when the object representation was inhibited by T1 processing, the AB effect spread across the object groupings showing an enhanced same-object AB effect; when the object representation was created before T1 processing, there was a reliably reduced same-object AB effect that was not mediated by OBA (i.e., no difference in T2 performance between the same and different objects). Additionally, a horizontal configuration benefit independent of OBA was obtained in the AB.

When is object-based attention not based on objects?

Some studies using methods introduced by Egly, Driver, and Rafal (1994) to measure object-based attention have shown surprising effects of object orientation. Rectangles oriented horizontally produce evidence for object-based attention, whereas vertical rectangles do not. We explore these differences using a two-letter comparison task. Across all the experiments, responses are faster when the targets are arranged horizontally rather than vertically. The horizontal advantage persists when the rectangles are removed, demonstrating its independence from object-based attention. Furthermore, responses are faster for vertically configured targets when they are within the same rectangle. This effect only arises when the rectangle orientation is informative about the target configuration orientation. This same-object advantage would normally be attributed to object-based attention, but the same pattern of data emerged when the rectangles were replaced with a salient orientation cue. The rectangles can apparently serve as a cue, making the cuing effect appear to be an object-based attention effect. However, the cuing effect can also be triggered by a horizontal bar in the center of the display. Thus participants can adopt an attentional set for a horizontal orientation independently of stimulus location. Results from comparison tasks that might have been attributed to object-based attention could instead be due to a combination of a horizontal advantage and an orientation set cost. Although these results lead to a diminished role for object-based attention, they also call for a better understanding of how an attentional set can be adopted without selecting either locations or objects. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Object-based attention in complex, naturalistic auditory streams

In vision, objects have been described as the ‘units’ on which non-spatial attention operates in many natural settings. Here, we test the idea of object-based attention in the auditory domain within ecologically valid auditory scenes, composed of two spatially and temporally overlapping sound streams (speech signal vs. environmental soundscapes in Experiment 1 and two speech signals in Experiment 2). Top-down attention was directed to one or the other auditory stream by a non-spatial cue. To test for high-level, object-based attention effects we introduce an auditory repetition detection task in which participants have to detect brief repetitions of auditory objects, ruling out any possible confounds with spatial or feature-based attention. The participants’ responses were significantly faster and more accurate in the valid cue condition compared to the invalid cue condition, indicating a robust cue-validity effect of high-level, object-based auditory attention.

Spatial attention is necessary for object-based attention: Evidence from temporal-order judgments

Attentional selection is a dynamic process that relies on multiple types of representations. That object representations contribute to attentional selection has been known for decades; however, most evidence for this contribution has been gleaned from studies that have relied on various forms of spatial cueing (some endogenous and some exogenous). It has thus remained unclear whether object-based attentional selection is a direct result of spatial cuing, or whether it still emerges without any spatial marker. Here we used a novel method-the temporal-order judgment (TOJ)-to examine whether object-based guidance emerges in the absence of spatial cuing. Participants were presented with two rectangles oriented either horizontally or vertically. Following a 150-ms preview time, two target stimuli were presented on the same or on different objects, and participants were asked to report which of the two stimuli had appeared first. The targets consisted of stimuli that formed a percept of a "hole" or a "hill." First, we demonstrated that the "hill" target was indeed processed faster, as evidenced by a positive perceived simultaneity (PSS) measure. We then demonstrated that if two targets appeared with equal probabilities on the same and on different objects, the PSS values, although positive, were not modulated by the objects. In a subsequent set of experiments, we showed that objects can modulate attentional allocation-however, only when they are biased by a spatial (endogenous) cue. In other words, in the absence of a spatial cue or bias, object representations do not guide attentional selection. In addition to providing new constraints for theories of object-based attentional guidance, these experiments introduce a novel paradigm for measuring object-based attentional effects.

Object formation in visual working memory: Evidence from object-based attention

We report on how visual working memory (VWM) forms intact perceptual representations of visual objects using sub-object elements. Specifically, when objects were divided into fragments and sequentially encoded into VWM, the fragments were involuntarily integrated into objects in VWM, as evidenced by the occurrence of both positive and negative object-based attention effects: In Experiment 1, when subjects’ attention was cued to a location occupied by the VWM object, the target presented at the location of that object was perceived as occurring earlier than that presented at the location of a different object. In Experiment 2, responses to a target were significantly slower when a distractor was presented at the same location as the cued object (Experiment 2). These results suggest that object fragments can be integrated into objects within VWM in a manner similar to that of visual perception.

Visual field meridians modulate the reallocation of object-based attention.

Object-based attention (OBA) enhances processing within the boundaries of a selected object. Larger OBA effects have been observed for horizontal compared to vertical rectangles, which were eliminated when controlling for attention shifts across the visual field meridians. We aimed to elucidate the modulatory role of the meridians on OBA. We hypothesized that the contralateral organization of visual cortex accounts for these differences in OBA prioritization. Participants viewed "L"-shaped objects and, following a peripheral cue at the object vertex, detected the presence of a target at the cued location (valid), or at a non-cued location (invalid) offset either horizontally or vertically. In Experiment 1, the single displayed object contained components crossing both meridians. In Experiment 2, one cued object and one non-cued object were displayed such that both crossed the meridians. In Experiment 3, one cued object was sequestered into one screen quadrant, with its vertex either near or far from fixation. Results from Experiments 1 and 2 revealed a horizontal shift advantage (faster RTs for horizontal shifts across the vertical meridian compared to vertical shifts across the horizontal meridian), regardless of whether shifts take place within a cued object (Experiment 1) or between objects (Experiment 2). Results from Experiment 3 revealed no difference between horizontal and vertical shifts for objects that were positioned far from fixation, although the horizontal shift advantage reappeared for objects near fixation. These findings suggest a critical modulatory role of visual field meridians in the efficiency of reorienting object-based attention.

Exploring the relationship between object realism and object-based attention effects

Visual attention prioritizes processing of locations in space, and evidence also suggests that the benefits of attention can be shaped by the presence of objects (object-based attention). However, the prevalence of object-based attention effects has been called into question recently by evidence from a large-sampled study employing classic attention paradigms (Pilz et al., 2012). We conducted two experiments to explore factors that might determine when and if object-based attention effects are observed, focusing on the degree to which the concreteness and realism of objects might contribute to these effects. We adapted the classic attention paradigm first reported by Egly, Driver, and Rafal (1994) by replacing abstract bar stimuli in some conditions with objects that were more concrete and familiar to participants: items of silverware. Furthermore, we varied the realism of these items of silverware, presenting either cartoon versions or photo-realistic versions. Contrary to predictions, increased realism did not increase the size of object-based effects. In fact, no clear object-based effects were observed in either experiment, consistent with previous failures to replicate these effects in similar paradigms. While object-based attention may exist, and may have important influences on how we parse the visual world, these and other findings suggest that the two-object paradigm typically relied upon to study object-based effects may not be the best paradigm to investigate these issues.

Exogenous attention to unseen objects?

Attention and awareness are closely related phenomena, but recent evidence has shown that not all attended stimuli give rise to awareness. Controversy still remains over whether, and the extent to which, a dissociation between attention and awareness encompasses all forms of attention. For example, it has been suggested that attention without awareness is more readily demonstrated for voluntary, endogenous attention than its reflexive, exogenous counterpart. Here we examine whether exogenous attentional cueing can have selective behavioural effects on stimuli that nevertheless remain unseen. Using a task in which object-based attention has been shown in the absence of awareness, we remove all possible contingencies between cues and target stimuli to ensure that any cueing effects must be under purely exogenous control, and find evidence of exogenous object-based attention without awareness. In a second experiment we address whether this dissociation crucially depends on the method used to establish that the objects indeed remain unseen. Specifically, to confirm that objects are unseen we adopt appropriate signal detection task procedures, including those that retain parity with the primary attentional task (by requiring participants to discriminate the two types of trial that are used to measure an effect of attention). We show a significant object-based attention effect is apparent under conditions where the selected object indeed remains undetectable.

Activity in human visual and parietal cortex reveals object-based attention in working memory.

Visual attention enables observers to select behaviorally relevant information based on spatial locations, features, or objects. Attentional selection is not limited to physically present visual information, but can also operate on internal representations maintained in working memory (WM) in service of higher-order cognition. However, only little is known about whether attention to WM contents follows the same principles as attention to sensory stimuli. To address this question, we investigated in humans whether the typically observed effects of object-based attention in perception are also evident for object-based attentional selection of internal object representations in WM. In full accordance with effects in visual perception, the key behavioral and neuronal characteristics of object-based attention were observed in WM. Specifically, we found that reaction times were shorter when shifting attention to memory positions located on the currently attended object compared with equidistant positions on a different object. Furthermore, functional magnetic resonance imaging and multivariate pattern analysis of visuotopic activity in visual (areas V1-V4) and parietal cortex revealed that directing attention to one position of an object held in WM also enhanced brain activation for other positions on the same object, suggesting that attentional selection in WM activates the entire object. This study demonstrated that all characteristic features of object-based attention are present in WM and thus follows the same principles as in perception.

Exploring the Relationship between Object-Based Attention Effects and Object Realism

Exploring the Relationship between Object-Based Attention Effects and Object Realism

Visual statistical learning can drive object-based attentional selection.

Recent work on statistical learning has demonstrated that environmental regularities can influence aspects of perception, such as familiarity judgments. Here, we ask if statistical co-occurrences accumulated from visual statistical learning could form objects that serve as the units of attention (i.e., object-based attention). Experiment 1 demonstrated that, after observers first viewed pairs of shapes that co-occurred in particular spatial relationships, they were able to recognize the co-occurring pairs, and were faster to discriminate two targets when they appeared within a learned pair ("object") than when the targets appeared between learned pairs, demonstrating an equivalent of an object-based attention effect. Experiment 2 replicated the results of Experiment 1 using a different set of shape pairs, and revealed a negative association between the attention effect and familiarity judgments of the co-occurred pairs. Experiment 3 reports three control experiments that validated the task procedure and ruled out alternative accounts.

Attention can operate on semantic objects defined by individual Chinese characters

Attention can select perceptual objects, but it is less clear whether attention can operate on objects defined by higher level cognition, such as semantic associations. Recent studies have shown that attention may be based on objects defined by Chinese two-character compound words, suggesting that attention can operate on semantic objects. In the present study, object-based attention (OBA) effect was investigated at the level of individual Chinese characters, and the role of character structure and radical order in OBA was explored by using a spatial cueing paradigm. In Experiment 1, we found OBA effect for conditions that had legal radical order, but not for other conditions in which the radical order information was disrupted. Character structure, however, had no influence on the OBA effect. In Experiment 2, we observed OBA effect for all conditions after enhancing the radical order and character structure information by adding perceptual cues. The results extend previous findings of a “semantic object”-based attention effect from the two-character word level to the individual character level. Moreover, we found that radical order but not character structure was important for this semantic OBA effect. We conclude that visual attention can be based on semantic objects at the level of individual characters, and that the development of semantic objects is affected by the perceptual grouping of the radicals.