Impaired configural body processing in anorexia nervosa: Evidence from the body inversion effect

Patients with anorexia nervosa (AN) suffer from severe disturbances of body perception. It is unclear, however, whether such disturbances are linked to specific alterations in the processing of body configurations with respect to the local processing of body part details. Here, we compared a consecutive sample of 12 AN patients with a group of 12 age‐, gender‐ and education‐matched controls using an inversion effect paradigm requiring the visual discrimination of upright and inverted pictures of whole bodies, faces and objects. The AN patients presented selective deficits in the discrimination of upright body stimuli, which requires configural processing. Conversely, patients and controls showed comparable abilities in the discrimination of inverted bodies, which involves only detail‐based processing, and in the discrimination of both upright and inverted faces and objects. Importantly, the body inversion effect negatively correlated with the persistence scores at the Temperament and Character Inventory, which evaluates increased tendency to convert a signal of punishment into a signal of reinforcement. These results suggest that the deficits of configural processing in AN patients may be associated with their obsessive worries about body appearance and to the excessive attention to details that characterizes their general perceptual style.     

Infants detect changes in everyday scenes: The role of scene gist

When watching physical events, infants bring to bear prior knowledge about objects and readily detect changes that contradict physical rules. Here we investigate the possibility that scene gist may affect infants, as it affects adults, when detecting changes in everyday scenes. In Experiment 1, 15-month-old infants missed a perceptually salient change that preserved the gist of a generic outdoor scene; the same change was readily detected if infants had insufficient time to process the display and had to rely on perceptual information for change detection. In Experiment 2, 15-month-olds detected a perceptually subtle change that preserved the scene gist but violated the rule of object continuity, suggesting that physical rules may overpower scene gist in infants’ change detection. Finally, Experiments 3 and 4 provided converging evidence for the effects of scene gist, showing that 15-month-olds missed a perceptually salient change that preserved the gist and detected a perceptually subtle change that disrupted the gist. Together, these results suggest that prior knowledge, including scene knowledge and physical knowledge, affects the process by which infants maintain their representations of everyday scenes.     

Sequential detection of learning in cognitive diagnosis

In order to look more closely at the many particular skills examinees utilize to answer items, cognitive diagnosis models have received much attention, and perhaps are preferable to item response models that ordinarily involve just one or a few broadly defined skills, when the objective is to hasten learning. If these fine‐grained skills can be identified, a sharpened focus on learning and remediation can be achieved. The focus here is on how to detect when learning has taken place for a particular attribute and efficiently guide a student through a sequence of items to ultimately attain mastery of all attributes while administering as few items as possible. This can be seen as a problem in sequential change‐point detection for which there is a long history and a well‐developed literature. Though some ad hoc rules for determining learning may be used, such as stopping after M consecutive items have been successfully answered, more efficient methods that are optimal under various conditions are available. The CUSUM, Shiryaev–Roberts and Shiryaev procedures can dramatically reduce the time required to detect learning while maintaining rigorous Type I error control, and they are studied in this context through simulation. Future directions for modelling and detection of learning are discussed.     

Not looking yourself: The cost of self‐selecting photographs for identity verification

Photo‐identification is based on the premise that photographs are representative of facial appearance. However, previous studies show that ratings of likeness vary across different photographs of the same face, suggesting that some images capture identity better than others. Two experiments were designed to examine the relationship between likeness judgments and face matching accuracy. In Experiment 1, we compared unfamiliar face matching accuracy for self‐selected and other‐selected high‐likeness images. Surprisingly, images selected by previously unfamiliar viewers – after very limited exposure to a target face – were more accurately matched than self‐selected images chosen by the target identity themselves. Results also revealed extremely low inter‐rater agreement in ratings of likeness across participants, suggesting that perceptions of image resemblance are inherently unstable. In Experiment 2, we test whether the cost of self‐selection can be explained by this general disagreement in likeness judgments between individual raters. We find that averaging across rankings by multiple raters produces image selections that provide superior identification accuracy. However, benefit of other‐selection persisted for single raters, suggesting that inaccurate representations of self interfere with our ability to judge which images faithfully represent our current appearance.     

The effect of display timing on change blindness in pigeons (Columba livia)

Change blindness is a phenomenon in which even obvious changes in a visual scene may go unnoticed. Recent research has indicated that this phenomenon may not be exclusive to humans. Two experiments investigated change blindness in pigeons, using a variant of the widely‐used flicker task to investigate the influence of display timing on change blindness. Results indicate that the duration of time during which a stimulus display is visible influences change detection accuracy, with the effect due to additional search time. The results are discussed in relation to the value of comparative cognition and cross‐species investigations of behavior.     

Objects that induce face pareidolia are prioritized by the visual system

The human visual system has evolved specialized neural mechanisms to rapidly detect faces. Its broad tuning for facial features is thought to underlie the illusory perception of faces in inanimate objects, a phenomenon called face pareidolia. Recent studies on face pareidolia suggest that the mechanisms underlying face processing, at least at the early stages of visual encoding, may treat objects that resemble faces as real faces; prioritizing their detection. In our study, we used breaking continuous flash suppression (b-CFS) to examine whether the human visual system prioritizes the detection of objects that induce face pareidolia over stimuli matched for object content. Similar to previous b-CFS results using real face stimuli, we found that participants detected the objects with pareidolia faces faster than object-matched control stimuli. Given that face pareidolia has been more frequently reported amongst individuals prone to hallucinations, we also explored whether this rapid prioritization is intact in individuals with schizophrenia, and found evidence suggesting that it was. Our findings suggest that face pareidolia engages a broadly tuned mechanism that facilitates rapid face detection. This may involve the proposed fast subcortical pathway that operates outside of visual awareness.     

目标决策还是动作诱发?动作反应对注意促进效应的影响

注意促进效应(ABE)指的是在双任务条件下, 伴随探测任务的目标刺激呈现的背景信息记忆成绩要优于伴随分心刺激呈现的背景信息记忆成绩的现象。以往研究主张, ABE的产生主要源于目标决策时所诱发的注意增强。但由于目标探测往往伴随着动作反应, 而已有研究发现, 动作反应就能直接诱发背景信息的记忆增强效应, 因此ABE也可能源于动作诱发的记忆增强效应。为此, 研究设置了NoGo目标探测条件与Go目标探测条件, 通过4个实验系统地探讨了动作反应与目标决策在ABE产生中的作用及关系。结果表明, Go目标探测条件下的ABE是稳定的, 但NoGo目标探测条件下的ABE会受到动作反应频率对分心词的影响。此外, NoGo目标探测跨条件的ABE也是非常稳定的。这些结果表明, 目标决策产生的注意促进作用是相对稳定的, 但ABE的产生更多是目标决策的促进作用与动作诱发的记忆增强效应动态权衡后的结果。     

面孔生命性加工的时间进程：ERP研究

本研究采用事件相关电位技术,通过参数设计考察了大脑加工面孔生命性时的神经电活动动态进程。结果显示：非生命性面孔比生命性面孔在中央顶区诱发了更大的LPP波幅;生命性和非生命性面孔诱发的LPP波幅均显著大于中间等级（60%）面孔,提示随生命性信息增强,LPP波幅呈“U”型变化。P1和N170未表现出面孔类别差异。结果表明LPP是探测面孔生命性加工的有效成分,支持面孔生命性加工位于面孔加工的晚期阶段的观点。     

Outgroup homogeneity effect in perception: An exploration with Ebbinghaus illusion

An outgroup homogeneity (OH) effect implies that outgroup members are perceived to be more similar than ingroup members. At present, however, it is not clear whether the OH effect is truly perceptual. Here, we used an Ebbinghaus illusion to demonstrate the OH effect in perception. Participants were presented with one central face that was surrounded by four surrounding faces. The central face was judged to be smaller as the size of the surrounding faces increased, thereby demonstrating an Ebbinghaus illusion. As predicted, however, this illusion was significantly greater when the faces allegedly belonged to an outgroup than when they allegedly belonged to an ingroup. This perceptual OH effect bore no significant relationship with cognitive OH measures. The perceptual versus cognitive OH effects might therefore be mediated by separate mechanisms.     

The movement of internal facial features elicits 7 to 8‐month‐old infants' preference for face patterns

A preference for static face patterns is observed in newborns and disappears around 3 months after birth. A previous study has demonstrated that 5‐month‐old infants prefer schematic faces only when the internal features are moving, suggesting that face‐specific movement enhances infants' preference. The present study investigates the facilitative effect of the movement of internal facial features on infants' preference. To examine infants' preference, we used animated face patterns consisting of a head‐shaped contour and three disk blobs. The inner blobs expanded and contracted to represent the opening and closing of the eyes and mouth, and were constrained to open and close only in a biologically possible vertical direction resembling the facial muscle structure. We compared infants' preferential looking time for this vertically moving (VM) face pattern with their looking time for a horizontally moving (HM) face pattern in which blobs transformed at the same speed in a biologically impossible, horizontal direction. In Experiment 1, 7 to 8‐month‐olds preferred the VM to the HM, but 5 to 6‐month‐olds did not. However, the preference was diminished in both cases when the moving face patterns were presented without contour (Experiment 2). Our results suggest that internal facial features with vertical movements promote face preference in 7 to 8‐month‐olds. Copyright © 2011 John Wiley & Sons, Ltd.