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941.
It is often assumed that measures of temperament within individuals are more correlated to one another than to measures of problem solving. However, the exact relationship between temperament and problem-solving tasks remains unclear because large-scale studies have typically focused on each independently. To explore this relationship, we tested 119 prospective adolescent guide dogs on a battery of 11 temperament and problem-solving tasks. We then summarized the data using both confirmatory factor analysis and exploratory principal components analysis. Results of confirmatory analysis revealed that a priori separation of tests as measuring either temperament or problem solving led to weak results, poor model fit, some construct validity, and no predictive validity. In contrast, results of exploratory analysis were best summarized by principal components that mixed temperament and problem-solving traits. These components had both construct and predictive validity (i.e., association with success in the guide dog training program). We conclude that there is complex interplay between tasks of “temperament” and “problem solving” and that the study of both together will be more informative than approaches that consider either in isolation.  相似文献   
942.
Many children pass through a mirror stage in reading, where they write individual letters or digits in mirror and find it difficult to correctly utilize letters that are mirror images of one another (e.g., b and d). This phenomenon is thought to reflect the fact that the brain does not naturally discriminate left from right. Indeed, it has been argued that reading acquisition involves the inhibition of this default process. In the current study, we tested the ability of literate pigeons, which had learned to discriminate between 30 and 62 words from 7832 nonwords, to discriminate between words and their mirror counterparts. Subjects were sensitive to the left–right orientation of the individual letters, but not the order of letters within a word. This finding may reflect the fact that, in the absence of human-unique top-down processes, the inhibition of mirror generalization may be limited.  相似文献   
943.
The ability to inhibit unproductive motor responses triggered by salient stimuli is a fundamental inhibitory skill. Such motor self-regulation is thought to underlie more complex cognitive mechanisms, like self-control. Recently, a large-scale study, comparing 36 species, found that absolute brain size best predicted competence in motor inhibition, with great apes as the best performers. This was challenged when three Corvus species (corvids) were found to parallel great apes despite having much smaller absolute brain sizes. However, new analyses suggest that it is the number of pallial neurons, and not absolute brain size per se, that correlates with levels of motor inhibition. Both studies used the cylinder task, a detour-reaching test where food is presented behind a transparent barrier. We tested four species from the order Psittaciformes (parrots) on this task. Like corvids, many parrots have relatively large brains, high numbers of pallial neurons, and solve challenging cognitive tasks. Nonetheless, parrots performed markedly worse than the Corvus species in the cylinder task and exhibited strong learning effects in performance and response times. Our results suggest either that parrots are poor at controlling their motor impulses, and hence that pallial neuronal numbers do not always correlate with such skills, or that the widely used cylinder task may not be a good measure of motor inhibition.  相似文献   
944.
Change blindness is a phenomenon whereby changes to a stimulus are more likely go unnoticed under certain circumstances. Pigeons learned a change detection task, in which they observed sequential stimulus displays consisting of individual colors back-projected onto three response keys. The color of one response key changed during each sequence and pecks to the key that displayed the change were reinforced. Pigeons showed a change blindness effect, in that change detection accuracy was worse when there was an inter-stimulus interval interrupting the transition between consecutive stimulus displays. Birds successfully transferred to stimulus displays involving novel colors, indicating that pigeons learned a general change detection rule. Furthermore, analysis of responses to specific color combinations showed that pigeons could detect changes involving both spectral and non-spectral colors and that accuracy was better for changes involving greater differences in wavelength. These results build upon previous investigations of change blindness in both humans and pigeons and suggest that change blindness may be a general consequence of selective visual attention relevant to multiple species and stimulus dimensions.  相似文献   
945.
946.
Self-recognition is a trait presumed to be associated with high levels of cognition and something previously considered to be exclusive to humans and possibly apes. The most common test of self-recognition is the mark/mirror test of whether an animal can understand that it sees its own reflection in a mirror. The usual design is that an animal is marked with a colour spot somewhere on the body where the spot can only be seen by the animal by using a mirror. Very few species have passed this test, and among birds, only magpies have been affirmatively demonstrated to pass it. In this study, we tested great tits (Parus major), small passerines, that are known for their innovative foraging skills and good problem-solving abilities, in the mirror self-recognition test. We found no indication that they have any ability of this kind and believe that they are unlikely to be capable of this type of self-recognition.  相似文献   
947.
Most mammals can accomplish acoustic recognition of other individuals by means of “voice cues,” whereby characteristics of the vocal tract render vocalizations of an individual uniquely identifiable. However, sound production in dolphins takes place in gas-filled nasal sacs that are affected by pressure changes, potentially resulting in a lack of reliable voice cues. It is well known that bottlenose dolphins learn to produce individually distinctive signature whistles for individual recognition, but it is not known whether they may also use voice cues. To investigate this question, we played back non-signature whistles to wild dolphins during brief capture-release events in Sarasota Bay, Florida. We hypothesized that non-signature whistles, which have varied contours that can be shared among individuals, would be recognizable to dolphins only if they contained voice cues. Following established methodology used in two previous sets of playback experiments, we found that dolphins did not respond differentially to non-signature whistles of close relatives versus known unrelated individuals. In contrast, our previous studies showed that in an identical context, dolphins reacted strongly to hearing the signature whistle or even a synthetic version of the signature whistle of a close relative. Thus, we conclude that dolphins likely do not use voice cues to identify individuals. The low reliability of voice cues and the need for individual recognition were likely strong selective forces in the evolution of vocal learning in dolphins.  相似文献   
948.
This study proposed and tested a comprehensive, chained mediation model of university students’ academic performance. The hypothesized model included adaptive-positive and maladaptive-negative submodels. The structures and processes in the adaptive-positive submodel were hypothesized to facilitate students’ academic performance, whereas the structures and processes in the maladaptive-negative submodel were hypothesized to undermine it. A sample of 373 university students completed a set of questionnaires measuring their approaches to studying, positive and negative affect, evaluation anxiety, use of creative cognition, motivational orientations, and adaptive and maladaptive metacognitions. Participants’ end-of-semester and prior semester academic performance was retrieved from the university registry. A structural equation model explained 90 % of the variance in students’ future academic performance, supported all but one hypothesized intermediate paths, and revealed that only positive affect in studying and prior academic performance predict directly future academic performance. The theoretical and practical implications of these findings are outlined.  相似文献   
949.
According to the World Health Organization well-being has been defined as one outcome parameter indicating successful recovery from diseases. One disease causing significant psychosocial problems and distress is Gambling Disorder that is being characterized as a poorly controlled excessive engagement in gambling activities. While there are several studies investigating treatment-effects in patients with Gambling Disorder, the role of well-being as a complementary treatment outcome has not been studied so far. In our research project it was aimed to fill this gap by gathering data on changes of eudaimonic dimensions of well-being from 76 patients with Gambling Disorder before and 1 year after receiving inpatient treatment. At both waves (pretreatment and follow-up) we collected data regarding well-being (Ryff Scales of Well-being), psychopathological symptoms (SCL-9), and diagnostic criteria for Gambling Disorder (Lie/Bet-Questionnaire). We found some dimensions of well-being changing 1 year after treatment and that patients recovered from Gambling Disorder displayed significant increments in Autonomy and Environmental Mastery. In contrast, patients still meeting criteria for Gambling Disorder displayed well-being increments only in Environmental Mastery and decreases in Personal Growth and Positive Relations with Others. Only changes in Environmental Mastery and Self-Acceptance were significantly associated with decreases in psychosocial distress indicating that well-being is an additional indicator for treatment outcome. It was also intended to identify factors predicting increments in well-being. However, no relationships were found regarding demographics, clinical variables, or treatment parameters. It is proposed to acknowledge well-being as an additional indicator for treatment effects and suggested to implement therapeutic strategies for an early enhancement of well-being.  相似文献   
950.
This study is the first to investigate the factor structure of the Mental Health Continuum-Short Form (MHC-SF) in New Zealand. Towards this end, traditional Confirmatory Factor Analysis (CFA) and the new method of Exploratory Structural Equation Modeling (ESEM) were used. Both ESEM and CFA supported the tripartite model of mental well-being in comparison to the one- and two-factor models; however, ESEM provided better fit with the data. Moreover, interfactor correlations were considerably lower in ESEM than they were in CFA, indicating greater factor distinctiveness in ESEM. ESEM also revealed a number of important cross-loadings for items in the measurement model of the MHC-SF. The results supported full metric and full scalar invariance of the MHC-SF across gender. The attenuated correlations among well-being factors obtained by ESEM here provide an important insight about the ongoing controversy regarding the failure of empirical research to identify distinct eudaimonic and hedonic factors in well-being measures. An overreliance on CFA methods may have led the field to rely on inflated estimates of shared variance between eudaimonia and hedonia.  相似文献   
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