Effect of Stress Level on Different Forms of Self-Touch in Pre- and Postadolescent Girls

Self-touch serves for regulation of both hyper- and hypoarousal. It remains unclear if different forms of self-touch occur in different contexts, and if the regulatory mechanisms are learned or innate. The authors describe forms and context of self-touch, and explore age differences in stress processing. They analyzed hand movements of 10 pre- and 10 postadolescent girls in low-stress and high-stress settings and found 3 forms of self-touch. In postadolescent participants, self-touch 2 (irregular structure, rhythmical, medium intensity) and 3 (phasic structure, single accent, medium intensity) were used for self-regulation, whereas self-touch 1 (irregular structure, single accent, low intensity) had conversational reasons. Increasing immobility might represent the inward focus of stressed participants that tried to focus on the task. No differences were found for preadolescent participants. Differences between pre- and postadolescent participants might be due to brain development during adolescence.     

热手谬误和赌徒谬误心理机制研究述评

在知觉随机序列时,人们倾向于把序列中实际上各自独立的相邻结果看作是存在正相关或负相关的,而出现热手谬误或赌徒谬误,又称为随机序列中的正负近因效应。有关这两谬误最早的心理机制的探索中,Kahneman 和Tversky采用局部代表性启发法对此进行了解释。但是这种解释也存在诸多不足,因此近期的一些模型（因果模型、Urn模型、记忆模型、适应模型和两阶段格式塔模型）分别从不同角度对两种谬误提出了新的解释。最后文章指出研究方法、神经机制、个体差异以及生活中的应用是该领域研究的几个未来发展方向     

Roughness perception during the rubber hand illusion

Watching a rubber hand being stroked by a paintbrush while feeling identical stroking of one’s own occluded hand can create a compelling illusion that the seen hand becomes part of one’s own body. It has been suggested that this so-called rubber hand illusion (RHI) does not simply reflect a bottom–up multisensory integration process but that the illusion is also modulated by top–down, cognitive factors. Here we investigated for the first time whether the conceptual interpretation of the sensory quality of the visuotactile stimulation in terms of roughness can influence the occurrence of the illusion and vice versa, whether the presence of the RHI can modulate the perceived sensory quality of a given tactile stimulus (i.e., in terms of roughness). We used a classical RHI paradigm in which participants watched a rubber hand being stroked by either a piece of soft or rough fabric while they received synchronous or asynchronous tactile stimulation that was either congruent or incongruent with respect to the sensory quality of the material touching the rubber hand. (In)congruencies between the visual and tactile stimulation did neither affect the RHI on an implicit level nor on an explicit level, and the experience of the RHI in turn did not cause any modulations of the felt sensory quality of touch on participant’s own hand. These findings first suggest that the RHI seems to be resistant to top–down knowledge in terms of a conceptual interpretation of tactile sensations. Second, they argue against the hypothesis that participants own hand tends to disappear during the illusion and that the rubber hand actively replaces it.     

A strange hand: On self-recognition and recognition of another

This article provides a phenomenological analysis of the difference between self-recognition and recognition of another, while referring to some contemporary neuroscientific studies on the rubber hand illusion. It examines the difference between these two forms of recognition on the basis of Husserl’s and Merleau-Ponty’s work. It argues that both phenomenologies, despite their different views on inter-subjectivity, allow for the specificity of recognition of another. In explaining self-recognition, however, Husserl’s account seems less convincing. Research concerning the rubber hand illusion has confirmed that self-recognition involves more than an immediate experience of oneself. Merleau-Ponty’s later work, describing self-recognition as the result of assimilative identification, will be used to explain the possibility of illusion between one’s “hereness” and “thereness”. The possibility of this illusion is inherent to self-recognition, while it is lacking in recognition of another.

The effects of blocking mouthing of leisure items on their effectiveness as reinforcers

Leisure items are commonly used as reinforcers in behavior-analytic applications. However, a defining feature of autism is the occurrence of stereotypy, and individuals with autism often engage leisure items in a stereotyped manner. The opportunity for stereotyped interaction may be the only aspect of a contingent stimulus that makes it a reinforcer for appropriate behavior. Therefore, this study investigated the effects of blocking stereotyped reinforcer interaction on reinforcer efficacy for 2 children with autism. Results showed that blocking stereotypic reinforcer interaction did not influence reinforcer efficacy.     

Spatial limits on referred touch to an alien limb may reflect boundaries of visuo-tactile peripersonal space surrounding the hand

In this study, the spatial limits of referred touch to a rubber hand were investigated. Participants rated the strength of the perceived illusion when the rubber hand was placed in one of six different spatial positions (at a distance of 17.5-67.5cm horizontal from the participant's own hand). The results revealed a significant nonlinear relationship in the strength of the illusion, with the strongest ratings given when the two hands were closest; decaying significantly after a distance of 30cm. The time taken to elicit the illusion followed a similar trend. These results may reflect the response properties of bimodal visuo-tactile cells encoding peripersonal space around the hand.     

Seeing an image of the hand affects performance on a crossmodal congruency task for sequences of events

The crossmodal congruency effect (CCE) is augmented when viewing an image of a hand compared to an object. It is unclear if this contextual effect extends to a non-spatial CCE. Here, participants discriminated the number of tactile vibrations delivered to the hand whilst ignoring visual distractors on images of their own or another’s hand or an object. The CCE was not modulated by stimulus context. Viewing one’s hand from a third person perspective increased errors relative to viewing an object (Experiment 1). Errors were reduced when viewing hands, from first or third person perspectives, with additional identity markers (Experiments 2 and 3). Our results suggest no effect of context on the non-spatial CCE and that differences in task performance between hand and object images depend on their visual properties. These findings are discussed in light of the relationship between body representation and perception of body-centred stimuli in the temporal domain.     

身体拥有感错觉对疼痛的影响及其作用机制

身体拥有感错觉以多通道的感官整合为基础,包括视觉-触觉、视觉-本体感觉、触觉-本体感觉、视觉-内感受的整合等。来自实验室急性痛以及慢性痛的大量结果表明拥有感错觉可产生镇痛作用。身体部位尺寸大小、肢体透明度等相关影响因素也逐渐得到揭示。拥有感错觉影响疼痛的机制与身体表征的改变有关,该过程可能涉及“身体网络”与“疼痛网络”间的连接,其中后顶叶皮层可能有重要作用。未来研究应更为深入地探索拥有感错觉范式以考察不同因素对疼痛的影响;在现有多感官整合的范式中重视内感受的作用;考察拥有感错觉改变疼痛的认知神经机制;区分急、慢性痛条件下以及不同慢性痛类型中拥有感错觉对疼痛的不同影响。     

2009年贵阳市住院儿童手足口病病原学及临床特点

为了解贵阳地区2009年4月~9月儿童手足口病的病原学及临床特点。从住院的820例手足口病患儿中采集部分伴有重症倾向的244例患儿的肛试子和咽试子标本进行RT-PCR技术检测,并进行临床观察。218例检测到肠道病毒,占89.34%,其中138例为EV71,占63.30%。72例为CA16,占33.02%,两者之比1.92:1。不同年龄组的病原构成差异有统计学意义(P0.01)。重症病例EV71感染明显高于轻症病例,两者在临床特征方面差异有统计学意义(P0.01)。2009年贵阳市住院儿童手足口病的主要病原是EV71和CA16;1岁~3岁的患儿EV71感染明显高于CA16,EV71比CA16更易引重症手足口病,重症病例与轻症病例在临床表现上有明显差异。     

AN ANALYSIS OF THE REINFORCING PROPERTIES OF HAND MOUTHING

Hand mouthing often has been described as a stereotypic response that is maintained by non-social (automatic) reinforcement; however, data supporting this conclusion can be found in relatively few studies. This series of studies presents an experimental analysis of conditions associated with the maintenance of hand mouthing. In Experiment 1, a functional analysis was conducted for 12 individuals who engaged in chronic hand mouthing to determine whether the behavior is usually maintained independent of social contingencies. Results obtained for 10 subjects were consistent with an automatic reinforcement hypothesis; the remaining 2 subjects' hand mouthing was maintained by social-positive reinforcement. Based on these results, Experiment 2 was designed to identify the specific reinforcing properties of hand mouthing. Each of 4 subjects was provided with a toy that substituted for hand mouthing, and preference for a specific topography of toy manipulation (hand-toy contact or mouth-toy contact) was measured. Results indicated that hand stimulation was the predominant reinforcer for all subjects. Experiment 3 provided an extension of Experiment 2 in that the same responses were measured across a variety of toys presented to each of 5 subjects. Results again indicated that hand stimulation was the predominant reinforcer for all subjects. Implications of these results are discussed with relevance to treatment.