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201.
The aim of the present investigation was to study the visual communication between humans and dogs in relatively complex situations. In the present research, we have modelled more lifelike situations in contrast to previous studies which often relied on using only two potential hiding locations and direct association between the communicative signal and the signalled object. In Study 1, we have provided the dogs with four potential hiding locations, two on each side of the experimenter to see whether dogs are able to choose the correct location based on the pointing gesture. In Study 2, dogs had to rely on a sequence of pointing gestures displayed by two different experimenters. We have investigated whether dogs are able to recognise an ‘indirect signal’, that is, a pointing toward a pointer. In Study 3, we have examined whether dogs can understand indirect information about a hidden object and direct the owner to the particular location. Study 1 has revealed that dogs are unlikely to rely on extrapolating precise linear vectors along the pointing arm when relying on human pointing gestures. Instead, they rely on a simple rule of following the side of the human gesturing. If there were more targets on the same side of the human, they showed a preference for the targets closer to the human. Study 2 has shown that dogs are able to rely on indirect pointing gestures but the individual performances suggest that this skill may be restricted to a certain level of complexity. In Study 3, we have found that dogs are able to localise the hidden object by utilising indirect human signals, and they are able to convey this information to their owner.  相似文献   
202.
Recent dog-infant comparisons have indicated that the experimenter's communicative signals in object hide-and-search tasks increase the probability of perseverative (A-not-B) errors in both species (Topál et al. 2009). These behaviourally similar results, however, might reflect different mechanisms in dogs and in children. Similar errors may occur if the motor response of retrieving the object during the A trials cannot be inhibited in the B trials or if the experimenter's movements and signals toward the A hiding place in the B trials ('sham-baiting') distract the dogs' attention. In order to test these hypotheses, we tested dogs similarly to Topál et al. (2009) but eliminated the motor search in the A trials and 'sham-baiting' in the B trials. We found that neither an inability to inhibit previously rewarded motor response nor insufficiencies in their working memory and/or attention skills can explain dogs' erroneous choices. Further, we replicated the finding that dogs have a strong tendency to commit the A-not-B error after ostensive-communicative hiding and demonstrated the crucial effect of socio-communicative cues as the A-not-B error diminishes when location B is ostensively enhanced. These findings further support the hypothesis that the dogs' A-not-B error may reflect a special sensitivity to human communicative cues. Such object-hiding and search tasks provide a typical case for how susceptibility to human social signals could (mis)lead domestic dogs.  相似文献   
203.
ObjectivesThe existence of exercise addiction has been examined in numerous studies. However, none of the measures developed for exercise addiction assessment have been validated on representative samples. Furthermore, estimates of exercise addiction prevalence in the general population are not available. The objective of the present study was to validate the Exercise Addiction Inventory (EAI; Terry, Szabo, & Griffiths, 2004), and the Exercise Dependence Scale (EDS; Hausenblas & Downs, 2002b), and to estimate the prevalence of exercise addiction in general population.DesignExercise addiction was assessed within the framework of the National Survey on Addiction Problems in Hungary (NSAPH), a national representative study for the population aged 18–64 years (N = 2710).Method474 people in the sample (57% males; mean age 33.2 years) who reported to exercise at least once a week were asked to complete the two questionnaires (EAI, EDS).ResultsConfirmatory Factor Analysis (CFA) indicated good fit both in the case of EAI (CFI = 0.971; TLI = 0.952; RMSEA = 0.052) and EDS (CFI = 0.938; TLI = 0.922; RMSEA = 0.049); and confirmed the factor structure of the two scales. The correlation between the two measures was high (r = 0.79). Results showed that 6.2% (EDS) and 10.1% (EAI) of the population were characterized as nondependent-symptomatic exercisers, while the proportion of the at-risk exercisers were 0.3% and 0.5%, respectively.ConclusionsBoth EAI and EDS proved to be a reliable assessment tool for exercise addiction, a phenomenon that is present in the 0.3–0.5% of the adult general population.  相似文献   
204.
ObjectiveThe main objective of the study was to examine the relation of different biological markers to a variety of pleasant and unpleasant psychobiosocial (PBS) states in response to precompetitive stress in sport.DesignA longitudinal design was adopted to assess biological markers and PBS states before several games.MethodA whole team of high-level professional basketball players (9 men, aged from 23 to 37 years) took part in the study. The biological measures included the salivary concentration of testosterone, cortisol, aamylase, and chromogranin A. The psychological measures involved emotional, cognitive, motivational, bodily, kinesthetic, performance, and communicative components of PBS states assessed according to the dimensions of their intensity, frequency, and direction (i.e., perceived effect on performance). Assessment was conducted within 1 h prior to competition on an approximately weekly basis across the whole championship for a total of 12 games played at the team's home.ResultsA series of canonical correlation analyses showed that an increase in the salivary concentration of biological variables was associated with enhanced intensity and frequency scores of pleasant PBS states, as well as enhanced directional values (i.e., perception of facilitative effects) of a range of both pleasant and unpleasant PBS states.ConclusionFindings suggest that elevation of testosterone, cortisol, α-amylase, and chromogranin A in basketball players prior to competition can have a perceived functional effect with respect to the upcoming performance.  相似文献   
205.
Almost 20?years ago, Jürgen Habermas launched the idea of constitutional patriotism as a proposed solution to the tension between citizenship and national identity in the European Union. Since then, constitutional patriotism has remained a key concept in debates on European Union (EU) citizenship and democracy. This article, as so many before it, scrutinizes the meaning and viability of the concept. Unlike most others, however, it focuses less on the content of the concept and more on the subjects to which it is assumed/supposed to apply. I argue, firstly, that constitutional patriotism is not a viable or even desirable ideal for the European demos in its totality. The potential patriots of the EU are not the large majority of European Union citizens who live in their home country but migrants from other member states and nonmember states who are foreigners in their host countries. Secondly and accordingly, I argue that advancing constitutional patriotism means improving the status of foreign nationals in general and third-country nationals in particular. Connecting the acquisition of EU citizenship to domicile as opposed to member state nationality is one venue for such improvement. I discuss what this could imply and defend it as a means of building a truly European demos.  相似文献   
206.
Sustained treatment attendance has been reported to be poor in publicly funded community-based clinic settings serving children and families. Several child and family characteristics have been shown to predict attendance in community-based care, but virtually no research has been conducted to examine how experiences in care, including psychotherapists' within-session practices, influence client attendance. The goal of this exploratory study was to examine how observed practice within sessions, in particular the extent to which therapists delivered elements consistent with evidence-based practices, impacts total number of sessions attended, while accounting for an array of other potential predictors. Participants include 181 children ages 4-13 and their parents entering a new episode of care for disruptive behavior problems in publicly funded clinics. Data sources include administrative billing records on treatment attendance; coded videotaped treatment sessions; and self-reports from children, parents, and therapists. Results indicate that parent education, service funding source, parent alliance with therapist, and therapist experience predicted number of sessions attended; intensity of evidence-based treatment techniques delivered to children was marginally associated with attendance (p = .059). Implications for improving engagement in community-based care are discussed.  相似文献   
207.
Monocular approaches to simultaneous localization and mapping (SLAM) have recently addressed with success the challenging problem of the fast computation of dense reconstructions from a single, moving camera. Thus, if these approaches initially relied on the detection of a reduced set of interest points to estimate the camera position and the map, they are currently able to reconstruct dense maps from a handheld camera while the camera coordinates are simultaneously computed. However, these maps of 3-dimensional points usually remain meaningless, that is, with no memorable items and without providing a way of encoding spatial relationships between objects and paths. In humans and mobile robotics, landmarks play a key role in the internalization of a spatial representation of an environment. They are memorable cues that can serve to define a region of the space or the location of other objects. In a topological representation of the space, landmarks can be identified and located according to its structural, perceptive or semantic significance and distinctiveness. But on the other hand, landmarks may be difficult to be located in a metric representation of the space. Restricted to the domain of visual landmarks, this work describes an approach where the map resulting from a point-based, monocular SLAM is annotated with the semantic information provided by a set of distinguished landmarks. Both features are obtained from the image. Hence, they can be linked by associating to each landmark all those point-based features that are superimposed to the landmark in a given image (key-frame). Visual landmarks will be obtained by means of an object-based, bottom-up attention mechanism, which will extract from the image a set of proto-objects. These proto-objects could not be always associated with natural objects, but they will typically constitute significant parts of these scene objects and can be appropriately annotated with semantic information. Moreover, they will be affine covariant regions, that is, they will be invariant to affine transformation, being detected under different viewing conditions (view-point angle, rotation, scale, etc.). Monocular SLAM will be solved using the accurate parallel tracking and mapping (PTAM) framework by Klein and Murray in Proceedings of IEEE/ACM international symposium on mixed and augmented reality, 2007.  相似文献   
208.
Recent studies on the conceptualization of abstract concepts suggest that the concept of time is represented along a left-right horizontal axis, such that left-to-right readers represent past on the left and future on the right. Although it has been demonstrated with strong consistency that the localization (left or right) of visual stimuli could modulate temporal judgments, results obtained with auditory stimuli are more puzzling, with both failures and successes at finding the effect in the literature. The present study supports an account based on the relative relevance of visual versus auditory-spatial information in the creation of a frame of reference to map time: The auditory location of words interacted with their temporal meaning only when auditory information was made more relevant than visual spatial information by blindfolding participants.  相似文献   
209.
People often encounter self-control challenges in complex everyday environments in which objects that promote a given goal (e.g., to eat healthily) are mixed together with objects that obstruct that goal. For example, healthy and unhealthy food choices are often mixed together in restaurant menus. Because local processing facilitates attention to low-level details, we expect that it may play an important role in these complex situations. In the present studies, we test the hypothesis that local processing supports self-control when goal items and temptations are contextually paired. As predicted, our findings revealed that local processing (relative to global processing) increased evaluations of healthy items when those items were presented together with unhealthy items. As hypothesized, this effect of local processing only occurred when healthy and unhealthy foods were presented as complementary – not competing – options, suggesting that local processing may increase evaluations of healthy options by decreasing the extent to which individuals accept environmental cues that healthy and unhealthy foods belong together. These findings support recent research demonstrating that despite strong evidence of the advantages of global processing for self-control, local processing may also support self-control efforts in some important everyday situations.  相似文献   
210.
Three studies examined how the use of the present versus the past tense in recalling a past experience influences behavioral intentions. Experiment 1 revealed a stronger influence of past behaviors on drinking intentions when participants self-reported an episode of excessive drinking using the present tense. Correspondingly, there was a stronger influence of attitudes towards excessive drinking when participants self-reported the episode in the past tense. Experiments 2 and 3 liked this effect to changes in construal level (Liberman, Trope, & Stephan, 2007; Trope & Liberman, 2003), with the present tense being similar to a concrete construal level and the past tense being similar to an abstract construal level.  相似文献   
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