Exploring the breadth of the top-down representations that control attentional disengagement

Recent studies attribute top-down control as the primary determinant of the speed with which attention can be disengaged from an object, and disengagement has received increased interest as a means to distinguish between top-down and bottom-up accounts of attention capture. We present the results of three experiments exploring the breadth of the representations that delay attentional disengagement based on top-down goals. Experiments 1 and 2 examined whether objects similar to an observers' search target, but differing in luminance and hue, delayed the reallocation of attention in a search paradigm designed to isolate disengagement time. Experiment 3 explored whether the representations that delay disengagement are based on absolute similarity with the search target, or are tuned based on target/nontarget relationships. These three studies confirmed the role of top-down goals in automatically contributing to dwell times and revealed that the representations that underlie disengagement effects are broad (automatically delaying disengagement for items similar, but not identical to, the search target). In some cases, attention sets appeared to be graded in nature, but in others target–distractor relationships influenced the degree to which an irrelevant item held attention. Implications for theories of attention capture and potential functional significance of these automatic effects are discussed.     

Early adolescents show sustained susceptibility to cognitive interference by emotional distractors

A child's ability to continuously pay attention to a cognitive task is often challenged by distracting events. Distraction is especially detrimental in a learning or classroom environment in which attended information is typically associated with establishing skills and knowledge. Here we report a study examining the effect of emotional distractors on performance in a subsequent visual lexical decision task in 11- to 13-year-old students (n=30). Lexical decisions about neutral verbs and verb-like pseudowords (i.e., targets) were analysed as a function of the preceding distractor type (pleasant, neutral, or unpleasant photos) and the picture–target stimulus-onset asynchrony (SOA; 200 or 600 ms). Across distractor categories, emotionally arousing pictures prolonged decisions about word targets when compared to neutral pictures, irrespective of the SOA. The present results demonstrate that similar to adults, early adolescent students exhibit sustained susceptibility to cognitive interference by irrelevant emotional events.     

Emotional triangles: A test of emotion-based attentional capture by simple geometric shapes

Previous work has proposed that simple geometric shapes, carrying the features present within negative or threatening faces are especially effective at capturing or guiding attention. Here we test this account and provide converging evidence for a threat-based attentional advantage. Experiment 1 found that downward-pointing triangles continue to be detected more efficiently than upward-pointing triangles when: (i) both overall RT and search slope measures are obtained; and (ii) when the set size is varied and the stimuli are presented in random configurations. Experiment 2 tested and ruled out an alternative account of the selection advantage, based on differences between triangle shape consistencies with scene perspective cues. Overall, the data provide converging evidence that simple geometric shapes, which might be particularly important in providing emotional signals in faces, can also attract attention preferentially even when presented outside of a face context.     

Visual field asymmetry in attentional capture

The present study examined the spatial distribution of involuntary attentional capture over the two visual hemi-fields. A new experiment, and an analysis of three previous experiments showed that distractors in the left visual field that matched a sought-for target in color produced a much larger capture effect than identical distractors in the right visual field, revealing a visual field asymmetry in color-based contingent capture. On the other hand, abrupt onsets in the two hemi-fields did not differ in the magnitude of their capture effect, indicating a symmetric distribution of onset capture. The different spatial patterns for contingent capture and onset capture reveal differences between the two types of attentional capture, possibly indicating differences in the underlying brain mechanisms.     

Awareness of the saccade goal in oculomotor selection: Your eyes go before you know

The aim of the present study was to investigate how saccadic selection relates to people’s awareness of the saliency and identity of a saccade goal. Observers were instructed to make an eye movement to either the most salient line segment (Experiment 1) or the only right-tilted element (Experiment 2) in a visual search display. The display was masked contingent on the first eye movement and after each trial observers indicated whether or not they had correctly selected the target. Whereas people’s awareness concerning the saliency of the saccade goal was generally low, their awareness concerning the identity was high. Observers’ awareness of the saccade goal was not related to saccadic performance. Whereas saccadic selection consistently varied as a function of saccade latency, people’s awareness concerning the saliency or identity of the saccade goal did not. The results suggest that saccadic selection is primarily driven by subconscious processes.     

Valuable orientations capture attention

Visual attention has long been known to be drawn to stimuli that are physically salient or congruent with task-specific goals. Several recent studies have shown that attention is also captured by stimuli that are neither salient nor task relevant, but that are rendered in a colour that has previously been associated with reward. We investigated whether another feature dimension—orientation—can be associated with reward via learning and thereby elicit value-driven attentional capture. In a training phase, participants received a monetary reward for identifying the colour of Gabor patches exhibiting one of two target orientations. A subsequent test phase in which no reward was delivered required participants to search for Gabor patches exhibiting one of two spatial frequencies (orientation was now irrelevant to the task). Previously rewarded orientations robustly captured attention. We conclude that reward learning can imbue features other than colour—in this case, specific orientations—with persistent value.     

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.     

Does the form of employment make a difference?—Commitment of traditional, temporary, and self-employed workers

Increasing change in the labor market has produced new forms of employment. A growing number of people have temporary jobs or are self-employed freelancers. The aim of our study is to address these changes by introducing commitment to the form of employment as a new focus in commitment. In addition, we compare organizational commitment under conditions of these forms of employment to traditional form of employment. The study is based on several samples representing conventional and new forms of employment (overall N = 494). The results indicate that commitment to the form of employment explains variance of organizational outcomes over and above organizational commitment. Generally, commitment to the form of employment reflects an important attitude to the work situation besides commitment to the organization or occupation. The results are discussed in the light of labor market trends.     

视觉搜索中基于工作记忆内容的注意捕获与抑制

注意是对有关信息的选择及对无关信息的抑制, 工作记忆是对有关信息的保持以及对无关信息的抑制, 两者在一定程度上都体现了选择性地指向与当前任务有关的刺激并同时抑制无关刺激。在系统地回顾已有研究的基础上结合新近的ERP研究, 从视觉搜索中基于工作记忆内容的注意捕获与注意抑制两个角度综述了视觉工作记忆与视觉选择性注意的相关研究。研究者们主要从两方面对该领域的问题进行了探讨：(1)视觉工作记忆内容对视觉选择性注意的导向作用; (2)视觉工作记忆内容对视觉选择性注意产生导向作用的条件。文章对以往的研究进行了总结, 指出了无论保持在视觉工作记忆的内容是捕获注意还是受到抑制, 都存在着自上而下和自下而上两种加工机制。     

跨感觉通道任务中刺激驱动注意捕获的不对称性

通过两个实验探讨了来自不同感觉通道或不同空间方位的奇异刺激在视听搜索范式中的注意捕获。实验一使用定位任务探讨刺激驱动注意捕获中跨通道效应且及其不对称性, 结果发现, 当靶子在听觉通道时, 只有来自听觉同侧空间方位的奇异刺激成功的捕获了注意; 而来自视觉同侧空间和异侧空间的奇异刺激并没有捕获注意。实验二使用检测任务进一步探讨刺激驱动的注意捕获中的跨通道效应且具有不对称性, 结果发现, 来自同侧和异侧的听觉奇异刺激均捕获了注意, 但是视觉奇异刺激却不能捕获注意。研究表明, 视听搜索范式中的奇异刺激的注意捕获具有不对称性, 且存在着一种超感觉通道的注意资源。