知觉与行为的分离在视错觉研究中的验证

知觉与行为的分离是指人的视觉对物体的知觉与对行为的控制属于两个不同的系统。最早人们从临床病例中发现存在知觉与行为的分离,以后Aglioti等利用铁钦纳错觉实验证实正常人中也存在这一分离现象。一些研究者将两者的分离看作是两个不同视觉皮层通路（腹侧知觉系统和背侧视觉运动系统）的结果。围绕这一分离现象的实验和假说引发了不少的争论。该文回顾了十年来利用错觉实验所做的众多验证性研究,分析了支持和否定分离现象存在的各类证据,对一些重要结果和观点进行了总结,并由此提出了自己的看法。     

"旁观者清"还是"旁观者不清"?——偏向知觉的非对称性研究

心理学家近年来开始重视人们对社会认知偏向的知觉的研究。文章回顾了心理学对偏向以及对偏向知觉的研究历史,重点介绍了“偏向盲点”与“内省错觉”两种偏向知觉的实验,分析了偏向知觉的相关理论解释,并提出偏向知觉研究是社会知觉研究的一个新领域。     

Valuing thoughts, ignoring behavior: The introspection illusion as a source of the bias blind spot

People see themselves as less susceptible to bias than others. We show that a source of this bias blind spot involves the value that people place, and believe they should place, on introspective information (relative to behavioral information) when assessing bias in themselves versus others. Participants considered introspective information more than behavioral information for assessing bias in themselves, but not others. This divergence did not arise simply from differences in introspective access. The blind spot persisted when observers had access to the introspections of the actor whose bias they judged. And, participants claimed that they, but not their peers, should rely on introspections when making self-assessments of bias. Only after being educated about the importance of nonconscious processes in guiding judgment and action—and thereby about the fallibility of introspection—did participants cease denying their relative susceptibility to bias.     

The spatial distance rule in the moving and classical rubber hand illusions

The rubber hand illusion (RHI) is a perceptual illusion in which participants perceive a model hand as part of their own body. Here, through the use of one questionnaire experiment and two proprioceptive drift experiments, we investigated the effect of distance (12, 27.5, and 43 cm) in the vertical plane on both the moving and classical RHI. In both versions of the illusion, we found an effect of distance on ownership of the rubber hand for both measures tested. Our results further suggested that the moving RHI might follow a narrower spatial rule. Finally, whereas ownership of the moving rubber hand was affected by distance, this was not the case for agency, which was present at all distances tested. In sum, the present results generalize the spatial distance rule in terms of ownership to the vertical plane of space and demonstrate that also the moving RHI obeys this rule.     

The role of agency for perceived ownership in the virtual hand illusion

The rubber hand illusion shows that people can perceive artificial effectors as part of their own body under suitable conditions, and the virtual hand illusion shows the same for virtual effectors. In this study, we compared a virtual version of the rubber-hand setup with a virtual-hand setup, and manipulated the synchrony between stimulation or movement of a virtual “effector” and stimulation or movement of people’s own hand, the similarity between virtual effector and people’s own hand, and the degree of agency (the degree to which the virtual effector could be controlled by people’s own movements). Synchrony-induced ownership illusion was strongly affected by agency but not similarity, which is inconsistent with top-down modulation approaches but consistent with bottom-up approaches to ownership. However, both agency and similarity induce a general bias towards perceiving an object as part of one’s body, suggesting that ownership judgments integrate various sources of information.     

我是谁?——人际间多感觉刺激下的识脸错觉

识脸错觉是在人际间同步多感觉刺激下将他人面孔感知为自我面孔的一种主观体验。继Tsakiris报告了识脸错觉现象之后,研究者通过选取不同的刺激呈现方式、不同的被试,重点对被试的主观体验、行为反应两个方面进行了考察,并得到了大量新的研究成果;发现年龄、性别及内部敏感性是影响识脸错觉强度的重要因素,右侧颞顶联合区、顶内沟和枕下回的神经活动与被试主观报告的错觉体验强度相关。未来识脸错觉研究应侧重于研究策略的多样化并为生物特征识别中新模态的选择提供理论支持。此外,同步多感觉刺激技术的开发与应用将会对自我新面孔认同训练具有重要意义。     

Sense of body ownership in patients affected by functional motor symptoms (conversion disorder)

Background and aimPatients with functional neurological symptoms are commonly seen in neurological practice. Nevertheless their aetiopathology remains unclear. We have recently shown that patients affected by functional motor symptoms (FMS) present lower interoceptive awareness and higher alexithymia levels than healthy controls. Nevertheless sense of body ownership has never been studied in FMS patients.The aim of the present study was to systematically investigate the sense of body ownership, with the rubber hand illusion (RHI) paradigm, in patients with FMS and healthy controls.Materials and methodsWe included in the study 16 patients with FMS and 18 healthy controls (HC). Patients and HC were asked to complete the Toronto Alexithymia Scale (TAS-20) and the self-consciousness scale (self-objectification questionnaire). All participants underwent the RHI paradigm: illusionary experience was measured by self-report and by proprioceptive alteration.ResultsA Mann–Whitney U test performed revealed that FMS (median = 2.11) participants embodied the rubber hand to the same extent than HC participants (median = 2.0, Z = −0.86, p > 0.05, r = −0.15). The same test revealed no significant difference in the Proprioceptive Drift experience between FMS (median = 0.0) and HC participants (median = −0.5, Z = −0.96, p > 0.05, r = −0.16).ConclusionsOur study revealed that sense of body ownership is not impaired in patients affected by FMS. This, together with the results from our previous experiment (studying the interoceptive awareness), supports the hypothesis that interoceptive awareness and sense of body ownership may be dissociated in patients with FMS.     

自我表征的可塑性:基于橡胶手错觉的研究

自我识别是人类自我觉知的行为标记。传统方法认为稳定的自我表征是自我识别的基础。随着对橡胶手错觉及一系列自我表征和自我识别错觉的揭示,这一能让人将外部客体感知为自身一部分的错觉研究使得我们能够以多感官整合的方式来研究自我表征和自我识别。拥有感和自主感被认为是我们进行自我识别的两类基本体验,本文对一系列橡胶手错觉范式研究的系统回顾表明,拥有感和自主感会发生改变,这说明人的自我表征是可变的和可塑的。     

Illusion of safety? Safety-related perceptions of pedestrians and car drivers around 3D crosswalks

Facilitating safe pedestrian road crossings is a major prerequisite for safe urban environments. In multiple cities around the world, 3D crosswalks have been painted, which provoke an optical illusion, of e.g., a crosswalk floating above the road, in car drivers who approach the crosswalk. However, to date, no detailed study of road users’ safety related perceptions on 3D crosswalks has been conducted. Hence, we investigated car drivers’ and pedestrians’ perceptions of a 3D crosswalk, and how they rate its safety in comparison to traditional (non-3D illusion) crosswalks. In an on-site questionnaire survey, we interviewed 201 pedestrians and 102 car drivers in the direct vicinity of a newly painted 3D crosswalk located in Yangon, Myanmar. Our results show that only 53.9 % of the car drivers report to have consciously perceived the 3D effect of the crosswalk. Nonetheless, both, pedestrians and car drivers rate the 3D crosswalk as safer for road crossing than a traditional crosswalk. A high share of pedestrians (43.3 %) report taking a detour to use the 3D crosswalk for road crossing. Approximately one third (31.3 %) of pedestrians and 48.0 % of car drivers interviewed have talked to their friends about the 3D crosswalk, indicating a high potential for using 3D crosswalks as a marketing tool for road safety actors to generate attention for pedestrian safety. Unrelated to our main research question, we found that pedestrians prefer to cross in groups, as it increases the perceived likelihood of cars yielding to them. Overall, the data points to significant increases in the perceived safety of drivers as well pedestrians around the 3D crosswalk. Future studies need to investigate how these perceptions translate to actual safety related behavior.     

The Goldilocks Problem of the specificity of visual phenomenal content

Existentialist accounts maintain that visual phenomenal content takes the logical form of an existentially quantified sentence. These accounts do not make phenomenal content specific enough. Singularist accounts posit a singular content in which the seen object is a constituent. These accounts make phenomenal content too specific. My account gets the specificity of visual phenomenal content just right. My account begins with John Searle's suggestion that visual experience represents an object as seen, moves this relation outside the scope of the existential quantifier and then replaces it with the relation of objects being ‘present as accessible’, as described by Alva Noë.