An object-based template for rejection effect

ABSTRACT

In the process of searching for targets, our visual system not only prioritizes target-relevant features, but can also suppress nontarget-related features. Although this template for rejection has been well demonstrated, whether the features (i.e. the objects) or locations are suppressed remains unresolved due to the experimental paradigms in previous studies: in particular, object-based templates for rejection were confounded with location-based inhibition in visual search paradigms. The present study examined an object-based template for rejection by introducing search arrays comprised of two overlapping shapes with search items distributed along the shape's contours. To discourage location-based inhibition, the two shapes were spatially intermingled (Experiment 1), rotated (Experiment 2), or jiggled (Experiment 3). Participants identified the colour of a target cross. The pre-cue indicated the shape in which the target would appear (positive cue condition), the shape in which only distractors would appear (negative cue condition), or the shape that was irrelevant to the current search array (neutral cue condition). In all three experiments, the reaction times for the negative cue condition were shorter than those for the neutral cue condition, which is a hallmark of the object-based template for rejection effect, even under conditions in which location-based inhibition was discouraged.     

Going the distance: Extra-symbolic contributions to the symbolic control of spatial attention

Over the past 30 years, researchers have used symbolic cues such as spatial words and arrows to direct observers' attention to the location of target objects that appear at a single, fixed distance in simple visual environments; however, they have done so by using symbolic cues that provide only partial—directional—information about the spatial location of target objects. Thus, it remains unclear whether observers can only shift their attention broadly in the cued direction in response to these cues or whether they can shift their attention to the specific location of the target by combining an expectation about direction (derived from apprehension of the directional cue) with an expectation about distance (derived from some extra-symbolic cue). The results of two experiments showed that observers do shift their attention to relatively coarse spatial locations by combining expectancies about direction and distance, and that the extent to which observers do so is modulated by the presence of visible markers and the expected distance of the target. These findings are important because they provide the first evidence that extra-symbolic information about distance contributes to the symbolic control of spatial attention.     

Involuntary attention in the absence of visual awareness

ABSTRACT

Previous studies have found a dissociation between voluntary attention and awareness. Here, we examined the relationship between involuntary attention and awareness. We presented a masked cue such that participants were unaware of the cue. This was followed by a search array, for which participants detected the presence of a shape target. Even though the cue was task irrelevant and unconscious, we observed faster reaction times when either the cue’s location or colour was congruent with shape target. We conclude an unconscious stimulus can elicit both space- and feature-based attention. These results provide further evidence for the dissociation between attention and consciousness.     

Mapping the timecourse of goal-directed attention to location and colour in human vision

Goal-directed attention prioritises perception of task-relevant stimuli according to location, features, or onset time. In this study we compared the behavioural timecourse of goal-directed selection to locations and colours by varying the stimulus-onset asynchrony (SOA) between cue and target in a strategic cueing paradigm. Participants reported the presence or absence of a target following prior information regarding its location or colour. Results revealed that preparatory selection by colour is more effective at enhancing perceptual sensitivity than selection by location, even though both types of cue provided equivalent overall information. More detailed analysis revealed that this advantage arose due a limitation of spatial attention in maintaining a sufficiently broad focus (>2°) for target detection across multiple stimuli. In contrast, when target stimuli fell within 2° of the spatial attention spotlight, the strategic advantages and speed of spatial and colour attention were equated. Our findings are consistent with the conclusion that, under spatially optimal conditions, prior spatial and colour information are equally proficient at guiding top-down selection. When spatial locations are ambiguous, however, colour-based selection is the more efficient mechanism.     

Spatial attention can be biased towards an expected dimension

A commonly held view in both exogenous and endogenous orienting is that spatial attention is associated with enhanced processing of all stimuli at the attended location. However, we often search for a specific target at a particular location, so an observer should be able to jointly specify the target identity and expected location. Whether attention can bias dimension-specific processes at a particular location is not yet clear. We used a dual task to examine the effects of endogenous spatial cues on the accuracy of perceptual judgments of different dimensions. Participants responded to a motion target and a colour target, presented at the same or different locations. We manipulated a central cue to predict the location of the motion or colour target. While overall performance in the two tasks was comparable, cueing effects were larger for the target whose location was predicted by the cue, implying that when attending a particular location, processing of the likely dimension was preferentially enhanced. Additionally, an asymmetry between the motion and colour tasks was seen; motion was modulated by attention, and colour was not. We conclude that attention has some ability to select a dimension at a particular location, indicating integration of spatial and feature-based attention.     

A glimpse is not a glimpse: Differential processing of flashed scene previews leads to differential target search benefits

The question of whether words can be identified without spatial attention has been a topic of considerable interest over the last five and a half decades, but the literature has yielded mixed conclusions. The present experiments manipulated the proportion of valid trials (the proportion of trials in which a cue appeared in the same location as the upcoming target word) so as to encourage distributed (50% valid cues; Experiments 1 and 3) or focused (100% valid cues; Experiments 2 and 4) spatial attention in a priming-type paradigm. Participants read aloud a target word, and the impact of a simultaneously presented distractor word was assessed. Semantic and orthographic priming effects were present when conditions promoted distributed spatial attention but absent when conditions promoted focused spatial attention. In contrast, Experiment 5 yielded a distractor word effect in the 100% valid cue condition when subjects identified a colour (Stroop task). We take these results to suggest that (1) spatial attention is a necessary preliminary to visual word recognition and (2) examining the role of spatial attention in the context of the Stroop task may have few implications for basic processes in reading because colour processing makes fewer demands on spatial attention than does visual word recognition.     

Attentional capture by singletons is contingent on top-down control settings: Evidence from electrophysiological measures

The present study examined whether the capture of spatial attention is driven by stimulus salience (e.g., object uniqueness) or by a match to current attentional control settings (contingent capture). We measured the N2pc effect, a component of the event-related brain potential thought to reflect lateralized attentional allocation. On every trial, a noninformative cue display containing a colour singleton box was followed by a target display of letters. Participants searched for a target letter in a specified colour (in Experiments 1–3) or within a specified shape (in Experiment 4) while ignoring other stimuli. The key manipulation was whether the singleton cue contained the target-defining feature (e.g., a specific colour). Experiment 1 revealed signs of attention capture—a cue validity effect and an N2pc effect—only for singleton cues that contained the target-defining feature. This pattern persisted even when we increased the salience of the singleton box (Experiments 2 and 3). Irrelevant colour singletons also failed to produce a significant N2pc effect when the target was defined based on shape rather than colour (Experiment 4). We conclude that attention capture is strongly contingent on top-down attentional control settings, not bottom-up stimulus salience.     

Effects of varying target luminance and cue luminance on attentional effects of spatial cues

Attentional effects of letter cues on target processing were investigated in a bilateral spatial cueing paradigm. Luminance contrast of the cue stimuli and of the target stimuli were both manipulated. Consistent with predictions derived from theoretical models of visual attention, manipulating cue luminance and target luminance had very different effects on performance. In agreement with the dorsal stream attention hypothesis (Marrett et al., 2011) orienting effects were unaffected by changes in cue luminance; but in agreement with the work of Reynolds, Pasternak, and Desimone (2000) and Carrasco, Ling, and Read (2004) orienting effects were strongly modulated by changes in the luminance and perceptual quality of the target. Theoretical implications of the results are considered and the data are explained in terms of a sensory enhancement effect, whereby attention amplifies the neuronal responses for attended stimuli.     

Attentional shift by eye gaze requires joint attention: Eye gaze cues are unique to shift attention1

Researchers have demonstrated that attentional shift triggered by gaze direction is reflexive. However, here we show that attentional shift by gaze direction was not always reflexive, but could be modulated by another's perspective. In Experiment 1, a schematic face's line of sight to a peripheral target was obstructed by a vertical barrier located between the face and the target under two conditions. However, the line of sight of the face was clear under another two conditions, in which the barrier was located behind the line of sight by utilizing a depth cue. The gaze cue shifted attention only when the line of sight was not blocked (i.e. joint attention was attained). The arrow cue did not shift attention regardless of the obstruction conditions in Experiment 2. These results suggest that attentional shift by gaze cues, but not arrow cues, involve a higher social cognitive process such as interpretation of the gaze.     

An electrophysiological study of attention capture by salience: Does rarity enable capture?

Several behavioural studies have suggested that rarity is critical for enabling irrelevant, salient objects to capture attention. We tested this hypothesis using the N2pc thought to reflect attentional allocation. A cue display was followed by a target display in which participants identified the letter in a specific colour. Experiment 1 pitted rare, irrelevant abrupt onset cues (appearing on only 20% of trials) against target-relevant colour cues. The relevant colour cue produced large N2pc and cue validity effects even when competing with a rare, salient, simultaneous abrupt onset. Similar results occurred even when abrupt onset frequency was reduced to only 10% of trials (Experiment 2). Experiment 3 examined rare, irrelevant colour singleton cues (20% of trials). Despite being rare and salient, these singleton cues produced no N2pc or cue validity effect indicating little attentional capture. Experiment 4 greatly increased colour cue salience by adding four background boxes, increasing colour contrast and tripling the cue display duration (from 50 to 150 ms). Small cue validity and N2pc effects were obtained, but did not strongly depend on degree of rarity (20% vs. 100%). We argue that rarity by itself is neither necessary nor sufficient to produce attention capture.     

Inhibition of return to color: A replication and nonextension of Law, Pratt, and Abrams (1995)

We presented subjects with an unpredictive cue that was followed after a 150- to 900-msec interstimulus interval (ISI) by a detection target. Cue and target were blue or red squares that appeared at fixation and in an otherwise uniform black field. In a filler condition, a task-irrelevant filler stimulus (magenta square) was presented during the ISI; in a no-filler condition, no stimulus appeared during the ISI. Using only a 900-msec ISI, Law, Pratt, and Abrams (1995) reported slower reaction times (RTs) when cue and target were the same color, but only when the task-irrelevant filler was presented during the ISI. They argued that attention is first drawn to the cue color and that inhibition of return (IOR; see Posner & Cohen, 1984) is established when attention is drawn away from that cue color representation by the task-irrelevant filler. Critical to their view is the assumption that IOR occurs only after attention is drawn away from the cue color by the filler. Assuming a time course for the withdrawal of attention from the cue color representation, Law et al. ’s view predicts growth of the inhibitory effect as a function of ISI in the filler condition as well as facilitation at early ISIs in the no-filler condition (because there is no filler to withdraw attention from the cue color). Contrary to these predictions, we found that the inhibitory effect observed by Law et al. at the 900-msec ISI was present at—and did not vary in magnitude across—the range of ISIs tested. And there was never facilitation in the no-filler condition. These results challenge Law et al. ’s inference that IOR for foveally presented colors was operating in their paradigm.     

Colour-cueing in visual search

Several studies have shown that people can selectively attend to stimulus colour, e.g., in visual search, and that preknowledge of a target colour can improve response speed/accuracy. The purpose was to use a form-identification task to determine whether valid colour precues can produce benefits and invalid cues costs. The subject had to identify the orientation of a "T"-shaped element in a ring of randomly-oriented "L"s when either two or four of the elements were differently coloured. Contrary to Moore and Egeth's (1998) recent findings, colour-based attention did affect performance under data-limited conditions: Colour cues produced benefits when processing load was high; when the load was reduced, they incurred only costs. Surprisingly, a valid colour cue succeeded in improving performance in the high-load condition even when its validity was reduced to the chance level. Overall, the results suggest that knowledge of a target colour does not facilitate the processing of the target, but makes it possible to prioritize it.     

成人去激活依恋策略和注意偏向：来自表情图片外源性提示点探测任务的证据

采用表情图片作为外源性提示的点探测任务,通过109名大学生探讨依恋倾向性和注意之间的关系。研究发现：依恋回避维度和三种面部表情的提示有效性指标呈现显著负相关;依恋回避高分组出现了提示有效性效应的消失和逆转;依恋焦虑维度和提示有效性、注意卷入和注意分离没有相关。结果表明：回避性依恋者对任何信息都存在回避性注意偏向;回避性注意偏向的强度随信息依恋效价的增强而增强;回避性注意偏向的出现为去激活策略的存在提供了跨文化证据。     

Crossmodal spatial attention shift produced by centrally presented gaze cues1

Abstract: Despite previous failures to identify visual‐upon‐auditory spatial‐cuing effects, recent studies have demonstrated that the abrupt onset of a lateralized visual stimulus triggers a shift of spatial attention in response to auditory judgment. Nevertheless, whether a centrally presented visual stimulus orients auditory attention remained unclear. The present study investigated whether centrally presented gaze cues trigger a reflexive shift of attention in response to auditory judgment. Participants fixated on a schematic face in which the eyes looked left or right (the cue). A target sound was then presented to the left or right of the cue. Participants judged the direction of the target as quickly as possible. Even though participants were told that the gaze direction did not predict the direction of the target, the response time was significantly faster when the gaze was in the target direction than when it was in the non‐target direction. These findings provide initial evidence for visual‐upon‐auditory spatial‐cuing effects produced by centrally presented cues, suggesting that a reflexive crossmodal shift of attention does occur with a centrally presented visual stimulus.     

Selective attention to the chemosensory modality

Previous studies have shown that behavioral responses to auditory, visual, and tactile stimuli are modulated by expectancies regarding the likely modality of an upcoming stimulus (see Spence & Driver, 1997). In the present study, we investigated whether people can also selectively attend to the chemosensory modality (involving responses to olfactory, chemical, and painful stimuli). Participants made speeded spatial discrimination responses (left vs. right) to an unpredictable sequence of odor and tactile targets. Odor stimuli were presented to either the left or the right nostril, embedded in a birhinally applied constant airstream. Tactile stimuli were presented to the left or the right hand. On each trial, a symbolic visual cue predicted the likely modality for the upcoming target (the cue was a valid predictor of the target modality on the majority of trials). Response latencies were faster when targets were presented in the expected modality than when they were presented in the unexpected modality, showing for the first time that behavioral responses to chemosensory stimuli can be modulated by selective attention.     

Shifts of spatial attention cued by irrelevant numbers: Electrophysiological evidence from a target discrimination task

Fischer et al. demonstrated that a centrally presented number can shift attention to the left/right when its magnitude is small/large. Two electrophysiological studies described these attentional effects as event-related potentials (ERPs) at centro-parietal sites. Since both studies used target detection tasks, it remains currently unknown whether similar results would be obtained with a discrimination task. We used ERPs to test whether digit cues also induce attention shifts when participants perform a feature-discrimination task on targets. ERPs were recorded whereas subjects discriminated the colour of lateral targets that were preceded by a central non-predictive digit. Analysis of cue-locked controlateral vs. ipsilateral ERP activity showed the emergence of early preparatory attention-directing components in parietal and frontal regions. Moreover, target-locked P1 components at occipito-parietal sites were significantly modulated by digit magnitude-target side congruency. These results demonstrate that irrelevant digit cues also bias sensory processing when embedded in a feature-discrimination task.     

A configural dominant account of contextual cueing: Configural cues are stronger than colour cues

Previous work has shown that reaction times to find a target in displays that have been repeated are faster than those for displays that have never been seen before. This learning effect, termed “contextual cueing” (CC), has been shown using contexts such as the configuration of the distractors in the display and the background colour. However, it is not clear how these two contexts interact to facilitate search. We investigated this here by comparing the strengths of these two cues when they appeared together. In Experiment 1, participants searched for a target that was cued by both colour and distractor configural cues, compared with when the target was only predicted by configural information. The results showed that the addition of a colour cue did not increase contextual cueing. In Experiment 2, participants searched for a target that was cued by both colour and distractor configuration compared with when the target was only cued by colour. The results showed that adding a predictive configural cue led to a stronger CC benefit. Experiments 3 and 4 tested the disruptive effects of removing either a learned colour cue or a learned configural cue and whether there was cue competition when colour and configural cues were presented together. Removing the configural cue was more disruptive to CC than removing colour, and configural learning was shown to overshadow the learning of colour cues. The data support a configural dominant account of CC, where configural cues act as the stronger cue in comparison to colour when they are presented together.     

内源性眼跳前的空间注意转移

采用线运动错觉(illusory line motion)测量的单任务范式,以色块为眼跳提示刺激,用三个实验对内源性眼跳前是否存在空间注意转移进行了探讨。实验一要求被试将眼睛跳往提示刺激处,通过对线运动错觉的分析确定该条件下的空间注意转移规律;实验二要求被试在将视线保持在注视点处的条件下判断目标色块是否出现,以探明线运动错觉是否受对目标色块前注意阶段加工的影响;实验三要求被试将眼睛跳往提示刺激的对侧,分析眼跳位置与提示刺激空间方位的一致性对空间注意转移的影响。获得以下主要结果：(1)内源性眼跳前存在注意转移;(2)在视线保持在注视点处的条件下,注意未受对提示刺激前注意加工的引导;(3)眼跳目标位置与提示目标位置的空间一致性对眼跳前空间注意转移无显著影响。     

Selectively ignoring locations does not modulate contingent involuntary orienting,but selectively attending does

Attending to a location in the visual field facilitates processing of objects in that location, and numerous studies have revealed processing benefits by precuing target locations. Recent studies have also demonstrated that precuing a location to ignore reduces distraction by items in that location; however, precuing a feature (colour) to ignore increases distractor interference, at least before a template for rejection is established. Thus, locations, not features, can be selectively ignored. The present study used a spatial cuing task to examine whether featurally-relevant items are selected when they appear in ignored locations. The results revealed contingent attentional capture by target-relevant cues (red cue when searching for red targets, but not for onset targets), even when the cue appeared in a location that was ignored. Importantly, this was equivalent to contingent capture elicited by cues in non-ignored locations. However, when observers were precued to the target location, contingent capture was largely eliminated. The results suggest salient items with target-relevant features are selected from selectively ignored locations, but focusing attention onto a location can preclude capture by salient and target-relevant items.     

三维倾斜平面的返回抑制

以随机点立体图为实验材料,采用三维空间线索－目标范式,将刺激呈现于同一视野位置以排除眼跳因素干扰,通过观察有意注意倾斜平面和无意注意倾斜平面与测试平面间的方向一致性和角度一致性对检测平面加工的影响,探讨了注意在不同倾斜平面间的转移是否产生返回抑制。结果表明：（1）以视差线索构造的三维视觉空间中,存在与注意有关的返回抑制效应;（2）无意注意加工能导致返回抑制,注意引导平面比无意注意平面引起更大的抑制效应。本研究的结果支持Posner返回抑制是由注意转移所致的观点