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911.
Dogs are able to flexibly adjust their social behaviour to situation-specific characteristics of their human partner’s behaviour in problem situations. However, dogs do not necessarily detect the specific role played by the human in a particular situation: they may form expectations about their partners’ behaviour based on previous experiences with them. Utilising inanimate objects (UMO—unidentified moving object) as interacting agents offers new possibilities for investigating social behaviour, because in this way we can remove or control the influence of previous experience with the partner. The aim of the present study was to investigate whether dogs are able to recognise the different roles of two UMOs and are able to adjust their communicative behaviour towards them. In the learning phase of the experiment, dogs were presented with a two-way food-retrieval problem in which two UMOs, which differed in their physical appearance and abilities, helped the dog obtain a piece of food in their own particular manner. After a short experience with both UMOs, dogs in the test phase faced one of the problems in the presence of both inanimate agents. Overall, dogs displayed similar levels of gazing behaviour towards the UMOs, but in the first test they looked, approached and touched the relevant partner first. This rapid adjustment of social behaviour towards UMOs suggests that dogs may generalise their experiences with humans to unfamiliar agents and are able to select the appropriate partner when facing a problem situation.  相似文献   
912.
Decision making can be a complex process requiring the integration of several attributes of choice options. Understanding the neural processes underlying (uncertain) investment decisions is an important topic in neuroeconomics. We analyzed functional magnetic resonance imaging (fMRI) data from an investment decision study for stimulus-related effects. We propose a new technique for identifying activated brain regions: cluster, estimation, activation, and decision method. Our analysis is focused on clusters of voxels rather than voxel units. Thus, we achieve a higher signal-to-noise ratio within the unit tested and a smaller number of hypothesis tests compared with the often used General Linear Model (GLM). We propose to first conduct the brain parcellation by applying spatially constrained spectral clustering. The information within each cluster can then be extracted by the flexible dynamic semiparametric factor model (DSFM) dimension reduction technique and finally be tested for differences in activation between conditions. This sequence of Cluster, Estimation, Activation, and Decision admits a model-free analysis of the local fMRI signal. Applying a GLM on the DSFM-based time series resulted in a significant correlation between the risk of choice options and changes in fMRI signal in the anterior insula and dorsomedial prefrontal cortex. Additionally, individual differences in decision-related reactions within the DSFM time series predicted individual differences in risk attitudes as modeled with the framework of the mean-variance model.  相似文献   
913.
Human and non‐human primates share the ability to extract adjacent dependencies and, under certain conditions, non‐adjacent dependencies (i.e., predictive relationships between elements that are separated by one or several intervening elements in a sequence). In this study, we explore the online extraction dynamics of non‐adjacent dependencies in humans and baboons using a serial reaction time task. Participants had to produce three‐target sequences containing deterministic relationships between the first and last target locations. In Experiment 1, participants from the two species could extract these non‐adjacent dependencies, but humans required less exposure than baboons. In Experiment 2, the data show for the first time in a non‐human primate species the successful generalization of sequential non‐adjacent dependencies over novel intervening items. These findings provide new evidence to further constrain current theories about the nature and the evolutionary origins of the learning mechanisms allowing the extraction of non‐adjacent dependencies.  相似文献   
914.
Rights, autonomy, privacy, and confidentialityare concepts commonly used in discussionsconcerning genetic information. When theseconcepts are thought of as denoting absolutenorms and values which cannot be overriden byother considerations, conflicts among themnaturally occur.In this paper, these and related notions areexamined in terms of the duties and obligationsmedical professionals and their clients canhave regarding genetic knowledge. It issuggested that while the prevailing idea ofautonomy is unhelpful in the analysis of theseduties, and the ensuing rights, an alternativereading of personal self-determination canprovide a firmer basis for ethical guidelinesand policies in this field.  相似文献   
915.
Chronic depression is assumed to be caused and maintained by interpersonal deficits. We describe the development and psychometric evaluation of the Interactive Test of Interpersonal Behavior (ITIB) that we developed for self‐assessment of these deficits. Participants with chronic depression (CD, N = 15), episodic depression (ED, N = 15) and healthy controls (HC, N = 15) participated in this pilot study. They completed the ITIB and a number of pen and paper questionnaires including the Lübeck Questionnaire of Preoperational Thinking (LQPT) and the inventory of interpersonal problems (IIP). The ITIB was highly acceptable for use in these participants. Internal consistency for the ITIB was adequate for group comparisons (Cronbach's alpha = 0.649). Item‐total correlations indicated adequate discriminatory power of five of the six items. The ITIB correlated moderately with the LQPT (= 0.524) and the IIP (= –0.568). The ITIB score differed significantly between the diagnostic groups (ANOVA F(2,42) = 6.22, = 0.004). It was the only measure that – albeit at a trend level – was associated with diagnostic group (CD vs. ED) on multinomial logistic regression analysis (B = 0.049 ± 0.029; OR 1.051; = 0.088). We found preliminary evidence that the ITIB is an acceptable and psychometrically adequate measure of interpersonal behavior that distinguishes between patients with CD and patients with ED. If replicated with an improved version of the test, our results could support the hypothesis that having interpersonal problems is a core deficit in patients with CD.  相似文献   
916.
917.
The authors investigated whether speakers who named several objects processed them sequentially or in parallel. Speakers named object triplets, arranged in a triangle, in the order left, right, and bottom object. The left object was easy or difficult to identify and name. During the saccade from the left to the right object, the right object shown at trial onset (the interloper) was replaced by a new object (the target), which the speakers named. Interloper and target were identical or unrelated objects, or they were conceptually unrelated objects with the same name (e.g., bat [animal] and [baseball] bat). The mean duration of the gazes to the target was shorter when interloper and target were identical or had the same name than when they were unrelated. The facilitatory effects of identical and homophonous interlopers were significantly larger when the left object was easy to process than when it was difficult to process. This interaction demonstrates that the speakers processed the left and right objects in parallel.  相似文献   
918.
Individual differences in impulsive traits have been associated with a number of deviant behaviors, and impulsivity has been assumed to play a critical role in the manifestation of violent and other criminal behavior. Despite frequent citations of a positive association between impulsivity and violence in persons with psychosis, conflicting findings in the research literature elicited this systematic review. The main aims were to examine the empirical evidence of the association and to determine whether the research design and measurement used were sufficient for testing a possible causal relationship. Two types of empirical evidence were searched for in keeping with the traditional trait-state dichotomy: documentation of the direct impact of impulsivity on carrying out the violent act (state), and documentation of elevated levels of impulsivity in a person and increased occurrence of violent acts (trait). Searches that were conducted in six databases resulted in one study that supported the association and three that did not. Only 2 out of 22 estimates obtained from bivariate analysis indicated evidence of an impulsivity–violence link. No single study had a design that yielded data on a direct impact of impulsivity on carrying out the violent act (i.e., the state aspect of the association).  相似文献   
919.
Dickinson and Szeligo (Can J Exp Psychol 62(4):211–222, 2008) found that processing time for simple visual stimuli was affected by the visual action participants had been instructed to perform on these stimuli (e.g., see, distinguish). It was concluded that these effects reflected the differences in the durations of these various visual actions, and the results were compared to participants’ subjective ratings of word meaning but it was also possible that word characteristics like length might have influenced response times. The present study takes advantage of word length differences between French and English visual action words in order to address this issue. The goals of the present study were to provide evidence that (1) the processing time differences previously found were due to differences in the cognitive actions represented by these words (and not due to characteristics to the words themselves), and (2) that individuals subjectively differentiate visual action words in such a way that allows for predictable differences in behaviour. Participants differentiated 14 French visual action words along two dimensions. Four of these words were then used in the instructions for a size-discrimination task. Processing time depended on the visual action word in the instruction to the task and differed in a predictable manner according to word meaning but not word length.  相似文献   
920.
Negative acknowledgement is an impression management technique that uses the admission of an unfavourable quality to mitigate a negative response. Although the technique has been clearly demonstrated, the underlying process is not well understood. The current research identifies a key mediator and moderator while also demonstrating that the effect extends beyond the specific acknowledged domain to the overall evaluation of a target object. The results of study 1 indicate that negative acknowledgement works through mitigating negatively valenced cognitive responses. People who are presented with a negative acknowledgement are less likely to counterargue when forming an evaluation. The results of study 2 reveal that individual differences in need for structure impact the effectiveness of the technique. People who are high in need for structure are more susceptible to the effect presumably because of their desire for easy-to-use information that aids the formation and maintenance of simple knowledge structures.  相似文献   
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