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11.
Visual working memory performance often declines when objects are tested in new positions from those they were observed. We report an asymmetry in repositioning costs for orientation compared to colour memory (Experiment 1). Follow-up experiments demonstrated a similar asymmetry for line length memory compared to shape memory (Experiment 2). When different shades of the same colour category were used, however, repositioning costs emerged for colour as well (Experiment 3). Finally, a direct comparison experiment demonstrated an asymmetry for orientation compared to categorical colours, but in a task with no explicit memory demands (Experiment 4). These results challenge previous accounts of repositioning costs, suggesting that they emerge not due to the contents of visual working memory, but naturally because of correspondence procedures that must be executed in order to use a memory to judge the present.  相似文献   
12.
The ε4 allele of the apolipoprotein E (APOE4) is associated with an increased risk of developing Alzheimer’s disease (AD). Hence, several studies have compared the brain characteristics of APOE4 carriers versus non-carriers in presymptomatic stages to determine early AD biomarkers. The present review provides an overview on APOE4-related brain changes in cognitively normal individuals, focusing on the main neuroimaging biomarkers for AD, i.e. cortical beta-amyloid (Aβ) deposition, hypometabolism and atrophy. The most consistent findings are observed with Aβ deposition as most studies report significantly higher cortical Aβ load in APOE4 carriers compared with non-carriers. Fluorodeoxyglucose-positron emission tomography studies are rare and tend to show hypometabolism in brain regions typically impaired in AD. Structural magnetic resonance imaging findings are the most numerous and also the most discrepant, showing atrophy in AD-sensitive regions in some studies but contradicting results as well. Altogether, this suggests a graded effect of APOE4, with a predominant effect on Aβ over brain structure and metabolism. Multimodal studies confirm this view and also suggest that APOE4 effects on brain structure and function are mediated by both Aβ-dependent and Aβ-independent pathological processes. Neuroimaging studies on asymptomatic APOE4 carriers offer relevant information to the understanding of early pathological mechanisms of the disease, although caution is needed as to whether APOE4 effects reflect AD pathological processes, and are representative of these effects in non-carriers.  相似文献   
13.
A large number of “unawareness” phenomena have been explained and quantified in terms of sensitivity (d′) fluctuations, with very few attempts at addressing an alternative putative cause, i.e., fluctuations of subjects’ response criteria (c). Response criteria fluctuations are particularly likely under dual-task paradigms with unbalanced sensitivities (Gorea & Sagi, 2000) such as those used in evidencing attentional blink (AB) and repetition blindness (RB) phenomena. The present study inquires into whether AB and RB are indeed prone to a deviant decisional behaviour. AB and RB were studied with a yes/no task allowing the assessment of d′ and c for the detection (presence/absence) of a target letter T2 as a function of its temporal lag relative to the presentation of another (AB) or of the same (RB) letter, T1 (Experiment 1). A significant criterion increase was observed in both cases. Additional experiments demonstrate that this criterion effect is typical of these dual-task AB and RB paradigms as it is not observed in a standard contrast detection task with mixed contrasts (Experiment 2), in a “control” AB design stripped off its first task T1 (Experiment 3), or in a metacontrast experiment (Experiment 4). We propose that the observed criterion shifts are the consequence of the inherent dual-task AB and RB designs (where observers have to judge two events of unequal saliencies) and that they entail an enhancement of the AB and RB effects as long as these effects are assessed via subjective (yes/no or matching) procedures.  相似文献   
14.
During the application of fingertip forces with simultaneous flexion of the four fingers, namely index, middle, ring, and little fingers, a stable force sharing among fingers is adopted. Several studies have hypothesized that this stable force sharing is established to minimize unnecessary rotational moments (different from the main flexion moments). This principle labeled "minimization of secondary moments" is presented in the literature as a principle used by the central nervous system to solve musculoskeletal redundancy. However, this principle has only been tested with one solicited degree of freedom and in one finger posture. Our study tests this principle with various degrees of freedom solicited as secondary moments and in two different finger postures. Participants (n=6) were asked to apply a downward vertical force using their four fingers with the forearm placed in two different configurations: a "horizontal" condition (involving flexion/extension and pronation/supination at the wrist joint) and a "vertical" condition (involving flexion/extension and radial/ulnar deviation at the wrist joint). Additionally, two finger postures were tested in each forearm configuration: in the first, the distal inter-phalangeal joints (DIP) were extended and the proximal inter-phalangeal joints (PIP) highly flexed. In the second finger posture, both DIP and PIP joints were flexed. The resultant four-finger force and the relative involvement of each finger in the resultant four-finger force (force sharing) were analyzed. Results showed that the finger postures did not influence the finger force sharing, showing that the minimization of the secondary moment principle was stable among the finger joint angle configurations. Nonetheless, the relative involvement of each finger was dependent on the secondary degree of freedom solicited (pronation/supination vs. radial/ulnar). The modifications of the finger force sharing between the "horizontal" and "vertical" conditions were in accordance with the principle of minimization of the secondary moments.  相似文献   
15.
The objectives of this exploratory study were to examine gender differences in physical self‐concept, and the influence of geographic place of residence on both adolescents' physical self‐concept and gender differences in physical self‐concept. The Physical Self Inventory was used to measure physical self‐perceptions and global self‐esteem. Participants were 323 boys and 282 girls living in the North or South of France. First a Mann‐Whitney U test was used to assess gender differences and the influence of geographic region differences on physical self‐perceptions (physical self‐worth, physical condition, sport competence, attractive body, physical strength) and global self‐esteem. Then a Kruskal‐Wallis ANOVA for ranked data was used to assess geographic region influence on boys' and girls' physical self‐concept and global self‐esteem. The results showed that not only did boys have significantly higher physical self scores (on all scales) and global self‐esteem than girls, but also that adolescents from the North of France had higher physical self scores (on all scales) and global self‐esteem than adolescents from the South. Moreover, many differences were found between boys and girls on physical self scores (on all scales) and global self‐esteem according to their geographic place of residence. The main results showed that girls from the South had lower scores on the attractive body, physical strength, physical self‐worth, and global self‐esteem scales than all other adolescents, and that boys from the South had lower scores on the attractive body and global self‐esteem scales than did boys and girls from the North.  相似文献   
16.
If his relationship to Sigmund Freud's psychoanalysis has been widely acknowledged, Claude Lévi‐Strauss’ rapport with C.G. Jung's analytical psychology remains quite obscure. While secondary commentary has been abundant, its approach has above all been intertextual, to the detriment of a rigorously historical reading. Even if certain arguments put forward by supporters of so‐called “influence” deserve to be taken into account, especially because they highlight Lévi‐Strauss ambiguities and paradoxes toward Jung, this paper provides proof that a precise reading of the texts, with the help of recent studies on the intellectual genesis of Lévi‐Strauss, lead to reject the thesis of an unstated debt owed by the French anthropologist to the Zurich psychologist.  相似文献   
17.
We present a procedure for checking sufficient completeness of conditional and constrained term rewriting systems containing axioms for constructors which may be constrained (by e.g. equalities, disequalities, ordering, membership, …). Such axioms allow to specify complex data structures like e.g. sets, sorted lists or powerlists. Our approach is integrated into a framework for inductive theorem proving based on tree grammars with constraints, a formalism which permits an exact representation of languages of ground constructor terms in normal form.The procedure is presented by an inference system which is shown sound and complete. A precondition of one inference of this system refers to a (undecidable) property called strong ground reducibility which is discharged to the above inductive theorem proving system. We have successfully applied our method to several examples, yielding readable proofs and, in case of negative answer, a counter-example suggesting how to complete the specification. Moreover, we show that it is a decision procedure when the TRS is unconditional but constrained, for an expressive class of constrained constructor axioms.  相似文献   
18.
The rapid evolution of information, communication and entertainment technologies will transform the lives of citizens and ultimately transform society. This paper focuses on ethical issues associated with the likely convergence of virtual realities (VR) and social networks (SNs), hereafter VRSNs. We examine a scenario in which a significant segment of the world’s population has a presence in a VRSN. Given the pace of technological development and the popularity of these new forms of social interaction, this scenario is plausible. However, it brings with it ethical problems. Two central ethical issues are addressed: those of privacy and those of autonomy. VRSNs pose threats to both privacy and autonomy. The threats to privacy can be broadly categorized as threats to informational privacy, threats to physical privacy, and threats to associational privacy. Each of these threats is further subdivided. The threats to autonomy can be broadly categorized as threats to freedom, to knowledge and to authenticity. Again, these three threats are divided into subcategories. Having categorized the main threats posed by VRSNs, a number of recommendations are provided so that policy-makers, developers, and users can make the best possible use of VRSNs.  相似文献   
19.
We tested the hypothesis that people show generality in their endorsement of unsubstantiated claims, employing more types of measures than used in previous studies. We found that measures of generic conspiracist ideation, specific fictitious conspiracy theory, and false conspiracy theory beliefs were all strongly and positively intercorrelated. A multiple regression analysis revealed that the measures of specific false and fictitious conspiracy theories both significantly predicted generic conspiracist ideation. A second broader test of the generality hypothesis showed that these measures of false and fictitious conspiracy belief were positively intercorrelated with measures of psychological misconceptions, pseudoscience, poorly supported psychological practices, and paranormal beliefs. However, the measures of misconceptions and pseudoscience displayed substantially lower correlations. The results provide support for the generality of acceptance of a wider variety of unsubstantiated claims than used in previous studies and also suggest differences in the types endorsed based on the kind of knowledge and content measured.  相似文献   
20.
In a lifelog, data from various sources are combined to form a record from which one can retrieve information about oneself and the environment in which one is situated. It could be considered similar to an automated biography. Lifelog technology is still at an early stage of development. However, the history of lifelogs so far shows a clear academic, corporate and governmental interest. Therefore, a thorough inquiry into the ethical aspects of lifelogs could prove beneficial to the responsible development of this field. This article maps the main ethically relevant challenges and opportunities associated with the further development of lifelog technologies as discussed in the scholarly literature. By identifying challenges and opportunities in the current debate, we were able to identify other challenges and opportunities left unmentioned. Some of these challenges are partly explained by a blind spot in the current debate. Whilst the current debate focuses mainly on lifelogs held by individuals, lifelogs held by governmental institutions and corporations pose idiosyncratic ethical concerns as well. We have provided a brief taxonomy of lifelog technology to show the variety in uses for lifelogs. In addition, we provided a general approach to alleviate the ethical challenges identified in the critical analysis.  相似文献   
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