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991.
In several previous studies, 18‐month‐old infants who were directly addressed demonstrated more robust imitative behaviors than infants who simply observed another's actions, leading theorists to suggest that child‐directed interactions carried unique informational value. However, these data came exclusively from cultural communities where direct teaching is commonplace, raising the possibility that the findings reflect regularities in infants' social experiences rather than responses to innate or a priori learning mechanisms. The current studies consider infants' imitative learning from child‐directed teaching and observed interaction in two cultural communities, a Yucatec Mayan village where infants have been described as experiencing relatively limited direct instruction (Study 1) and a US city where infants are regularly directly engaged (Study 2). Eighteen‐month‐old infants from each community participated in a within‐subjects study design where they were directly taught to use novel objects on one day and observed actors using different objects on another day. Mayan infants showed relative increases in imitative behaviors on their second visit to the lab as compared to their first visit, but there was no effect of condition. US infants showed no difference in imitative behavior in the child‐directed vs. observed conditions; however, infants who were directly addressed on their first visit showed significantly higher overall imitation rates than infants who observed on their first visit. Together, these findings call into question the idea that child‐directed teaching holds automatic or universal informational value.  相似文献   
992.
Theory and research on status attainment in work groups primarily focuses on members’ abilities and characteristics that make them appear competent as predictors of their status in the group. We complement the abilities perspective with a social identity perspective by arguing that another important determinant of a member’s status is based on the extent to which the member serves the group’s interests. Specifically, we assert that a member’s identification with the group affects performance on behalf of the group, which in turn affects other members’ assessment of the member’s status. We test this social identity perspective on status attainment by studying the influence of members’ group identification on their performance and status in the group, while controlling for the members’ abilities and status characteristics. In a three-wave longitudinal field study following 33 work groups during a six-month group project, we find that members’ identification enhances their performance on behalf of the group, which in turn increases their status within the group. As such, our study advances insights in the determinants of status attainment in work groups and points to the relevance of the social identity approach for research on the antecedents of status in work groups.  相似文献   
993.
Migration from different cultures carries with it some acclimatisation challenges. This study explored various health-seeking behaviours and potential barriers to healthcare utilisation among Nigerian Christians in the UK. This qualitative study involved 10 adult male and female participants, with both interviews and focus group discussion (FG) for data collection (Interviews: n?=?4, FG: n?=?6). Thematic analysis revealed that religious and cultural beliefs were barriers to healthcare utilisation. The implication is that further research on cultural matching between care providers and service users is needed; where religious leaders and health providers from Nigeria can influence health decisions among this migrant community. Limitations of the current study are discussed, with directions for further research identified.  相似文献   
994.
This study sought to develop and test a diagnostic tool for the measurement of professional human resource management (HRM) competencies in the South African context. Data on HRM competencies were collected from South African human resource (HR) practitioners (N = 189; females = 49.2%, blacks = 91.2%). Exploratory factor analyses resulted in three distinguishable HR competency dimensions: Professional behaviour and leadership (i.e. leadership-personal credibility, organisational capability, solution creation, interpersonal communication, and citizenship); Service orientation and execution (i.e. talent management, HR governance, analytics and measurement, and HR service delivery); and Business intelligence (i.e. strategic contribution, HR business knowledge, and HR technology).  相似文献   
995.
The aim of this article is to propose some benchmarks for a Doctor of Psychology (DPsych) in advanced training in Child Psychology in South Africa, and to highlight key elements in offering such a programme. In doing so, we use as case illustration an existing DPsych programme currently being offered at the University of the Free State, South Africa. We consider advanced child psychology training to registered psychologists in the clinical, counselling and educational categories. The DPsych option encompasses clinical practice, research, training, selection, and student outcomes in the context of theory as well as evidence-based practices. A wider adoption of a DPsych, focusing on child psychology, would add value to the integration of the best available research and clinical expertise in child mental health care in South Africa.  相似文献   
996.
997.
Physical cognition has generally been assessed in tool-using species that possess a relatively large brain size, such as corvids and apes. Parrots, like corvids and apes, also have large relative brain sizes, yet although parrots rarely use tools in the wild, growing evidence suggests comparable performances on physical cognition tasks. It is, however, unclear whether success on such tasks is facilitated by previous experience and training procedures. We therefore investigated physical comprehension of object relationships in two non-tool-using species of captive neotropical parrots on a new means-end paradigm, the Trap-Gaps task, using unfamiliar materials and modified training procedures that precluded procedural cues. Red-shouldered macaws (Diopsittaca nobilis) and black-headed caiques (Pionites melanocephala) were presented with an initial task that required them to discriminate between pulling food trays through gaps while attending to the respective width of the gaps and size of the trays. Subjects were then presented with a novel, but functionally equivalent, transfer task. Six of eight birds solved the initial task through trial-and-error learning. Four of these six birds solved the transfer task, with one caique demonstrating spontaneous comprehension. These findings suggest that non-tool-using parrots may possess capacities for sophisticated physical cognition by generalising previously learned rules across novel problems.  相似文献   
998.
Inspired by Spence’s seminal work on transposition, we propose a synthetic approach to understanding the temporal control of operant behavior. The approach takes as primitives the temporal generalization gradients obtained in prototypical concurrent and retrospective timing tasks and then combines them to synthetize more complex temporal performances. The approach is instantiated by the learning-to-time (LeT) model. The article is divided into three parts. In the first part, we review the basic findings concerning the generalization gradients observed in fixed-interval schedules, the peak procedure, and the temporal generalization procedure and then describe how LeT explains them. In the second part, we use LeT to derive by gradient combination the typical performances observed in mixed fixed-interval schedules, the free-operant psychophysical procedure, the temporal bisection task, and the double temporal bisection task. We also show how the model plays the role of a useful null hypothesis to examine whether temporal control in the bisection task is relative or absolute. In the third part, we identify a set of issues that must be solved to advance our understanding of temporal control, including the shape of the generalization gradients outside the range of trained stimulus durations, the nature of temporal memories, the influence of context on temporal learning, whether temporal control can be inhibitory, and whether temporal control is also relational. These issues attest to the heuristic value of a Spencean approach to temporal control.  相似文献   
999.
This study investigated the effects of environmental enrichment on the cognitive performance of female conventional farm (growing) pigs in a spatial holeboard task. Ten pairs of littermates matched for weight were used. From each litter, one piglet was randomly assigned to a barren environment; the other was assigned to an enriched environment from 4 weeks of age. The enriched environment was double the size of the barren environment, had a floor covered with straw, a rooting area filled with peat, and one of the four different enrichment toys which were exchanged daily. Starting at 11 weeks of age, all pigs were tested in a spatial holeboard discrimination task in which 4 out of 16 holes were baited. Furthermore, basal salivary cortisol levels of all pigs were determined after the end of all testing. All pigs were able to acquire the pattern of baited holes (acquisition phase, 40 trials) and the diagonally mirrored pattern (reversal phase, 20 trials). During the acquisition phase, the reference memory performance of the enriched-housed pigs was better than that of their barren-housed littermates, i.e. they reduced visits to the unbaited set of holes. During the reversal phase, enriched-housed pigs had a better general working memory performance than the barren-housed pigs as indicated by reduced revisits to holes already visited during a trial, irrespective of whether they were of the baited or the unbaited set. The enriched-housed pigs also searched for the hidden bait faster during both phases. The environments did not affect basal salivary cortisol levels. In conclusion, environmental enrichment slightly improved the cognitive performance of pigs in a spatial learning task. We hypothesise that the long period of habituation to and testing in the holeboard acted as enrichment that partially reduced the effects of barren housing.  相似文献   
1000.
Hala, Brown, McKay, and San Juan (2013) found that children as young as 2.5 years of age demonstrated high levels of accuracy when asked to recall whether they or the experimenter had carried out a particular action. In the research reported here, we examined the relation of early-emerging source monitoring to executive function abilities. Participants were children aged 2.5- to 3-years old. For the source-monitoring procedure, we used the Hala et al. (2013) task in which children and the experimenter took turns placing a total of 20 items on a model farm (encoding phase). For the source memory test, children were asked who had placed each item (retrieval phase). Executive function measures included assessments of working memory, delay-inhibitory control, and conflict-inhibitory control. The main finding was that inhibitory control measures were significantly related to performance on the source-monitoring task. This relation held for the conflict-inhibitory control measures even when controlling for age and vocabulary. The findings of this research suggest that even at the early age of 2.5 years, development of executive control is linked to the emergence of source-monitoring ability.  相似文献   
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