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751.
Tool use relies on numerous cognitive functions, including sustained attention and understanding of causality. In this study, we investigated the effects of tool-use training on cognitive performance in primates. Specifically, we applied the Primate Cognition Test Battery to three long-tailed macaques (Macaca fascicularis) at different stages of a training procedure that consisted of using a rake to retrieve out-of-reach food items. In addition, we evaluated a control group (n?=?3) performing a grasping task, in order to account for possible effects related to a simple motor act. Our results showed that tool-use training enhances mean performance in the physical cognition domain, i.e. the understanding of spatial relations, numerosity and causality. In particular, causal cognition (evaluating noise- and shape-related causality and understanding of tool properties) showed significant improvement after training, whereas spatial cognition (evaluating spatial memory, object permanence, rotation and transposition) showed a trend to improvement. Despite these findings, none of our trained monkeys succeeded in the tool-use task of the Primate Cognition Test Battery, which involved an unfamiliar tool. Some training-related effects did not persist after a 35-day resting period, suggesting that continuous practice may be necessary, or that a longer training period before resting may be needed to better maintain cognitive performance. In contrast with the training group, the control group did not display any change in cognitive performance. This finding paves the way to further investigation into the link between tool-use behaviour and the evolution of primate cognition. 相似文献
752.
The spatial-numerical association of response codes (SNARC) effect is the tendency for humans to respond faster to relatively larger numbers on the left or right (or with the left or right hand) and faster to relatively smaller numbers on the other side. This effect seems to occur due to a spatial representation of magnitude either in occurrence with a number line (wherein participants respond to relatively larger numbers faster on the right), other representations such as clock faces (responses are reversed from number lines), or culturally specific reading directions, begging the question as to whether the effect may be limited to humans. Given that a SNARC effect has emerged via a quantity judgement task in Western lowland gorillas and orangutans (Gazes et al., Cog 168:312–319, 2017), we examined patterns of response on a quantity discrimination task in American black bears, Western lowland gorillas, and humans for evidence of a SNARC effect. We found limited evidence for SNARC effect in American black bears and Western lowland gorillas. Furthermore, humans were inconsistent in direction and strength of effects, emphasizing the importance of standardizing methodology and analyses when comparing SNARC effects between species. These data reveal the importance of collecting data with humans in analogous procedures when testing nonhumans for effects assumed to bepresent in humans. 相似文献
753.
Biagio D’Aniello Gün Refik Semin Alessandra Alterisio Massimo Aria Anna Scandurra 《Animal cognition》2018,21(1):67-78
We report a study examining interspecies emotion transfer via body odors (chemosignals). Do human body odors (chemosignals) produced under emotional conditions of happiness and fear provide information that is detectable by pet dogs (Labrador and Golden retrievers)? The odor samples were collected from the axilla of male donors not involved in the main experiment. The experimental setup involved the co-presence of the dog’s owner, a stranger and the odor dispenser in a space where the dogs could move freely. There were three odor conditions [fear, happiness, and control (no sweat)] to which the dogs were assigned randomly. The dependent variables were the relevant behaviors of the dogs (e.g., approaching, interacting and gazing) directed to the three targets (owner, stranger, sweat dispenser) aside from the dogs’ stress and heart rate indicators. The results indicated with high accuracy that the dogs manifested the predicted behaviors in the three conditions. There were fewer and shorter owner directed behaviors and more stranger directed behaviors when they were in the “happy odor condition” compared to the fear odor and control conditions. In the fear odor condition, they displayed more stressful behaviors. The heart rate data in the control and happy conditions were significantly lower than in the fear condition. Our findings suggest that interspecies emotional communication is facilitated by chemosignals. 相似文献
754.
Claudia Marino C. M. Hirst C. Murray A. Vieno Marcantonio M. Spada 《Journal of Happiness Studies》2018,19(7):2009-2022
Recent research on Problematic Internet Use and Problematic Facebook Use (PIU and PFU) has focused on the idea that people who engage in PIU or PFU are more likely to present with mental health problems. The goal of the present study was to examine the contribution of positive mental health (PMH) to PIU and PFU among adolescents and young adults. A total of 1927 Italian adolescents and young adults participated in the study. Structural equation modeling showed that PMH is negatively linked to both PIU and PFU, indicating that PMH may be an important antecedent for both PIU and PFU among adolescents and young adults. In conclusion, dimensions of PMH may be taken into account by researchers and educational practitioners in preventing both PIU and PFU. 相似文献
755.
Muhammad Faress Bhuiyan 《Journal of Happiness Studies》2018,19(7):1935-1964
I examine the relationship between economic position relative to local neighbors and life satisfaction in rural Bangladesh. In particular, I exploit a novel household level census of three villages that includes the geospatial coordinates of every household and a perception measure of economic position relative to neighbors. This allows for exploring the sensitivity of the aforementioned relationship to (1) different objective definitions of neighborhood, and (2) the type of positional measure used, objective or perceived. I find that a higher perceived position improves life satisfaction while objective position has no statistically significant effect. This difference stems from a very low correlation between the objective and perceived positional measures. The low correlation can be explained by individual specific heterogeneity in definitions of neighbor. However, observable socioeconomic and demographic variables cannot explain the difference. 相似文献
756.
Amanda W. Y. Tan Charlotte K. Hemelrijk Suchinda Malaivijitnond Michael D. Gumert 《Animal cognition》2018,21(4):551-563
Examining how animals direct social learning during skill acquisition under natural conditions, generates data for examining hypotheses regarding how transmission biases influence cultural change in animal populations. We studied a population of macaques on Koram Island, Thailand, and examined model-based biases during interactions by unskilled individuals with tool-using group members. We first compared the prevalence of interactions (watching, obtaining food, object exploration) and proximity to tool users during interactions, in developing individuals (infants, juveniles) versus mature non-learners (adolescents, adults), to provide evidence that developing individuals are actively seeking information about tool use from social partners. All infants and juveniles, but only 49% of mature individuals carried out interacted with tool users. Macaques predominantly obtained food by scrounging or stealing, suggesting maximizing scrounging opportunities motivates interactions with tool users. However, while interactions by adults was limited to obtaining food, young macaques and particularly infants also watched tool users and explored objects, indicating additional interest in tool use itself. We then ran matrix correlations to identify interaction biases, and what attributes of tool users influenced these. Biases correlated with social affiliation, but macaques also preferentially targeted tool users that potentially increase scrounging and learning opportunities. Results suggest that social structure may constrain social learning, but the motivation to bias interactions towards tool users to maximize feeding opportunities may also socially modulate learning by facilitating close proximity to better tool users, and further interest in tool-use actions and materials, especially during development. 相似文献
757.
Kyung-Eun Yang 《Journal of International Migration and Integration》2018,19(1):91-110
This study aimed to empirically analyze the magnitude of discrimination within the South Korean labor market between immigrant and native women in light of different employment patterns. Using an extended version of the Oaxaca decomposition method, special analytical attention was paid to the heavy concentration of immigrant women in the informal sector of the labor market rather than the formal sector. The extensive data for the study came from the Korea National Survey of Multicultural Families and the 12th wave of the Korean Labor and Income Panel Study, both conducted in 2009. Overall, the results presented a strong case that immigrant women are more susceptible to discrimination than their native counterparts in terms of obtaining a secure job in the formal sector. After controlling for a range of individual characteristics, a significant proportion of this employment disparity remained unexplained, giving credence to the existence of systematic discrimination endemic in the labor market. 相似文献
758.
Anzhela Dolzhikova Victoria Kurilenko Yulia Biryukova Natalia Rumyantseva Ekaterina Kulikova Elena Tumakova 《Journal of International Migration and Integration》2018,19(1):181-194
The main purpose of this exploratory study is to work out and describe the labour migrant’s linguodidactic profile, to verify its didactic capacity of an instrument of pedagogic measurement of social, cognitive, ethnocultural, educational and other significant characteristics of migrants affecting the efficiency of the Russian language training courses. The interdisciplinary methodology of the research integrates principles and approaches of methods for teaching Russian as a foreign language, interdidactics, migration sociolology, culturology, anthropology and cognitive science. The Russian language training courses have a strong potential for linguocultural adaptation and integration of labour migrants because the language functions as a depository and translator of the hosting nation’s moral norms and values. The effectiveness of the Russian language training course depends upon the strict consideration of all significant characteristics of its addressees, i.e. labour migrants. These characteristics were identified and then integrated into the linguodidactic profile which was taken as a basis for the language training course. The didactic capacity of the linguodidactic profile was proved on the example of language teaching and testing of migrants from the Republic of Tajikistan, since foreigners from this country form the majority (47%) of labour immigration flows to the Russian Federation. The role and capacity of the linguodidactic profile in teaching Russian as a foreign language have been verified experimentally. The analyses and comparisons of the final examination results proved the efficiency of the training course worked out with consideration for the labour migrant’s typical linguodidactic profile and, consequently, its high didactic capacity. 相似文献
759.
Jeffrey Bloem Scott Loveridge 《Journal of International Migration and Integration》2018,19(2):233-251
In recent years, as the need for global refugee assistance has increased, so have fears and concerns of the costs of refugee resettlement in Western nations. Now, seemingly more than ever, international security and regional development depend largely on the composition and distribution of the world population. In many Western nations, dispersal policies are specifically designed to manage the distribution of recently arrived refugees. Secondary migration presents a challenge to the goals of dispersal policies and raises questions regarding regional development, population pressures, job security, welfare dependency, and the future of global refugee assistance. We survey administrators and caseworkers in a series of qualitative interviews about their experiences with secondary migration. We conclude that the US refugee resettlement system is ill-equipped in handling the complications of secondary migration. These results lead us to reimagine a better strategy for achieving the goals of refugee resettlement. 相似文献
760.
Onoso Imoagene 《Journal of International Migration and Integration》2018,19(2):497-512
This article discusses the workplace experiences of second-generation Nigerian adults in the USA. Drawing on data from semi-structured interviews with 67 respondents, I show that second-generation Nigerians differ in whether they perceive racial discrimination in the workplace. There was an almost even split between subjects who felt they had been discriminated against because of their race and those who said they had not experienced anti-black discrimination. For those who felt they had been racially discriminated against at work, their experiences took very similar forms to those of African Americans, with many drawing analogies between their workplace experiences and those of African Americans and other blacks. But there was evidence of intra-black dynamics with some experiencing ethnic discrimination from African Americans and some enjoying an advantage over African Americans because they are children of black immigrants. I showcase two strategic responses found among respondents: minimizing ethnic difference and stepping up one’s game, which were used to negotiate racism and achieve economic mobility. This is consistent with the minority cultures of mobility thesis; that minority groups have cultures of mobility that foster upward social mobility, and it challenges segmented assimilation theory’s perception that black immigrant groups and their children lack tenacity or adaptive strategies. 相似文献