当局者迷,旁观者清?自我-他人决策的理性差异及其机制

生活充满抉择,由于知识经验的局限,人们常需寻求他人建议,抑或直接请他人代己决策.诸多研究探讨了自我决策、向他人建议,以及代他人决策之间的差异.探究这种差异的动因之一在于考察何种条件下的决策更优或更“理性”.以往研究表明,自我决策或他人决策(向他人建议或代他人决策)均有可能更易违背理性决策原则,隐含着他人决策优于自我决策的“当局者迷,旁观者清”这一传统智慧有一定的边界条件.研究者一般从认知(建构水平理论)、情绪(类型和卷入度),以及动机(调节聚焦理论)三种视角对自我-他人决策差异进行解释.本文作者提出基于理由的决策(reason-based account)假设来解释自我-他人决策在理性程度上的差异.未来研究可从决策过程及脑机制上深入考察自我-他人决策差异及其机制.     

Perceptual grouping based on temporal structure: Impact of subliminal flicker and visual transients

In two experiments we examined the perceived grouping of grids of equidistant dots, which are rapidly modulated over time so that alternate rows or columns are presented out of phase. In Experiment 1, we report that observers were able to group the grids consistent with the temporal modulation reliably, even at contrasts/frequencies for which flicker was not detectable. Moreover, flicker thresholds decreased with stimulus duration, whilst grouping thresholds did not change. In Experiment 2, we examined the impact of visual transients, by measuring performance when, either a mask or a contrast ramp was presented before and after the stimulus. Performance dropped substantially for both conditions, but remained significantly above chance. The results are discussed in relation to the role of temporal correlations in stimulus modulations and visual transients in grouping.     

Reducing the own-race bias in face recognition by attentional shift using fixation crosses preceding the lower half of a face

Hills and Lewis (2006) reduced White participants’ own-race bias (ORB) in face recognition by training them to attend to features critical for Black faces (lower portion of the face). Here, the ORB was investigated following a brief fixation cross either in the upper portion of the face (critical for White faces) or the lower portion of the face. Results showed that when the cross preceded the lower portion of the face, Black faces were recognized more accurately than White faces and vice versa when it preceded the upper portion of the face. A second experiment demonstrated that this effect disappears if the participants are forced to delay their responses by 4 s. These results suggest that an immediate attentional mechanism can attenuate the ORB when immediate attention is paid to diagnostic features but this can be overridden with increased time spent viewing faces.     

Active suppression of distractors that match the contents of visual working memory

The biased competition theory proposes that items matching the contents of visual working memory will automatically have an advantage in the competition for attention. However, evidence for an automatic effect has been mixed, perhaps because the memory-driven attentional bias can be overcome by top-down suppression. To test this hypothesis, the Pd component of the event-related potential waveform was used as a marker of attentional suppression. While observers maintained a colour in working memory, task-irrelevant probe arrays were presented that contained an item matching the colour being held in memory. We found that the memory-matching probe elicited a Pd component, indicating that it was being actively suppressed. This result suggests that sensory inputs matching the information being held in visual working memory are automatically detected and generate an “attend-to-me” signal, but this signal can be overridden by an active suppression mechanism to prevent the actual capture of attention.     

Relationship between working memory capacity and contingent involuntary orienting

Individual differences in working memory capacity are related to the ability to control attention; where less working memory capacity is associated with less attentional control. A well-known demonstration of attentional control is contingent involuntary orienting (Folk, Remington, & Johnston, 1992), which is the finding that visuospatial attention is captured by a salient peripheral cue, but only if the cue is featurally similar to the target of search and not if the cue is featurally dissimilar. This control of attention and ability to resist shifting attention towards an irrelevant visual cue is believed to be moderated by attentional settings for target-specific features. This study establishes that working memory capacity is related to contingent involuntary orienting of attention. Lower working memory capacity was associated with larger stimulus-driven cueing effects at short cue-to-target onset asynchronies, than at longer asynchronies, suggesting working memory capacity was associated with the ability to control covert orienting of attention at early processing stages.     

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.     

When does feature search fail to protect against attentional capture?

ABSTRACT

When participants search for a shape (e.g., a circle) among a set of homogenous shapes (e.g., triangles) they are subject to distraction by colour singletons that are more salient than the target. However, when participants search for a shape among heterogeneous shapes, the presence of a non-target colour singleton does not slow responses to the target. Attempts have been made to explain these results from both bottom-up and top-down perspectives. What both accounts have in common is that they do not predict the occurrence of attentional capture on typical feature search displays. Here, we present a case where manipulating selection history, rather than the displays themselves, leads to attentional capture on feature search trials. The ability to map specific colours to the target and distractor appears to be what enables resistance to capture during feature search.     

Mind-reading without the scanner: Behavioural decoding of working memory content

ABSTRACT

Sophisticated machine learning algorithms have been successfully applied to functional neuroimaging data in order to characterize internal cognitive states. But is it possible to “mind-read” without the scanner? Capitalizing on the robust finding that the contents of working memory guide visual attention toward memory-matching objects, we trained a multivariate pattern classifier on behavioural indices of attentional guidance. Working memory representations were successfully decoded from behaviour alone, both within and between individuals. The current study provides a proof-of-concept for applying machine learning techniques to simple behavioural outputs (e.g., response times) in order to decode information about specific internal cognitive states.     

Categorical target templates: Typical category members are found and identified quickly during word-cued search

What information do people use to guide search when they lack precise details about the appearance of their target? In this study, we employed categorical (word-cued) search and eye tracking, to examine how category typicality influences search performance. We found that typical category members were fixated and identified more quickly than atypical categories. This finding held when the participant was cued at the superordinate level (finding “clothing” among non-clothing items) or the basic level (finding a “shirt” among other clothing items). This suggests that categorical target templates may be constructed by piecing together features from the most typical category member(s).     

Equally attending but still not seeing: An eye-tracking study of change detection in own- and other-race faces

The present study aimed to investigate whether the faster change detection in own-race faces in a change blindness paradigm, reported by Humphreys, Hodsoll, and Campbell (2005) and explained in terms of people's poorer ability to discriminate other-race faces, may be explained by people's preferential attention towards own-race faces. The study by Humphreys et al. was replicated using the same stimuli, while participants’ eye movements were recorded. These revealed that there was no attentional bias towards own-race faces (analysed in terms of fixation order, number, and duration), but people still detected changes in own-race faces faster than in other-race faces. The current results therefore give further support for the original claim that people are less sensitive to changes made in other-race faces, when own and other-race faces are equally attended.