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501.
Spatial representations of time are a ubiquitous feature of human cognition. Nevertheless, interesting sociolinguistic variations exist with respect to where in space people locate temporal constructs. For instance, while in English time metaphorically flows horizontally, in Mandarin an additional vertical dimension is employed. Noting that the bilingual mind can flexibly accommodate multiple representations, the present work explored whether Mandarin–English bilinguals possess two mental time lines. Across two experiments, we demonstrated that Mandarin–English bilinguals do indeed employ both horizontal and vertical representations of time. Importantly, subtle variations to cultural context were seen to shape how these time lines were deployed.  相似文献   
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503.
This study investigated the fine-grained development of the EEG power spectra in early adolescence, and the extent to which it is reflected in changes in peak frequency. It also sought to determine whether sex differences in the EEG power spectra reflect differential patterns of maturation. A group of 56 adolescents were tested at age 10 years and then at two further time-points approximately 18 months apart. The EEG was recorded during both eyes-closed and eyes-open conditions and Fourier transformed to provide estimates of absolute and relative spectral power at 0.5 Hz intervals from 0.5 to 40 Hz. The peak alpha frequency for each individual at each time-point was also determined for relative spectral power. Partial Least Squares (PLS) analysis was used to determine the combination of electrodes and frequencies that showed developmental change, or differed between the sexes. As a function of age, absolute delta and theta frequencies power decreased, and relative alpha2 and beta frequencies increased, replicating the standard findings of a decrease in lower, and increase in higher, frequencies with age. A small but significant increase in peak alpha frequency with age was detected. Moreover PLS analysis performed with individual alpha frequencies aligned to 10 Hz suggested that the age-related increase seen in alpha2 relative power was driven by changes in the peak frequency. Although males demonstrated higher alpha power than females, there were no sex differences in peak frequency, suggesting that there may be more to sex differences in EEG power than simply different rates of maturation between the two sexes.  相似文献   
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505.
Recent research with Rooks has demonstrated impressive tool-using abilities in captivity despite this species’ classification as a non-tool-user in the wild. Here, we explored whether another non-tool-using corvid, the Eurasian Jay, would be capable of similar feats and investigated the relative contributions of causal knowledge and instrumental conditioning to the birds’ performance on the tasks. Five jays were tested on a variety of tasks involving water displacement. Two birds reliably interacted with the apparatuses. In these tasks, both birds showed a preference for inserting stones into a tube containing liquid over a tube containing a solid or a baited ‘empty’ tube and also for inserting sinkable items over non-sinkable items into a tube of water. To investigate the contribution of instrumental conditioning, subjects were then tested on a series of tasks in which different cues were made available. It was found that, in the absence of any apparent causal cues, these birds showed a clear preference for the rewarded tube when the food incrementally approached with every stone insertion, but not when it simply “appeared” after the correct number of stone insertions. However, it was found that subjects did not prefer to insert stones into a tube rewarded by the incremental approach of food if the available causal cues violated the expectations created by existing causal knowledge (i.e. were counter-intuitive). An analysis of the proportion of correct and incorrect stone insertions made in each trial across tasks offering different types of information revealed that subjects were substantially more successful in experiments in which causal cues were available, but that rate of learning was comparable in all experiments. We suggest that these results indicate that Eurasian jays use the incremental approach of the food reward as a conditioned reinforcer allowing them to solve tasks involving raising the water level and that this learning is facilitated by the presence of causal cues.  相似文献   
506.
The relationship between individual humor styles and several organizational variables was investigated: stress, satisfaction with coworkers, team cooperation, and organizational commitment. Four humor styles from the Humor Styles Questionnaire were measured. Survey results of 349 participants indicated different humor styles (affiliative, self-enhancing, aggressive, and self-defeating) can have either a positive or negative effect on organizational outcomes. Results suggested that both researchers and practitioners can benefit from having a better understanding of how different humor styles affect people and outcomes in organizations.  相似文献   
507.
This article describes the development and validation of the Internalized Racial Oppression Scale (IROS) for Black individuals in 2 studies using a total sample of 468 Black college students. The IROS is intended to measure the degree to which racial oppression is internalized and replicated by Black individuals in the United States. An exploratory factor analysis suggested a five-factor solution: Belief in the Biased Representation of History (BRH), Devaluation of the African Worldview and Motifs (DAW), Alteration of Physical Appearance (APA), Internalization of Negative Stereotypes (INS), and Hair Change (HC). Confirmatory factory analysis supported an adequate model fit of a four-factor model: BRH, APA, INS, and HC. All factors of the IROS were positively correlated with the Pre-Encounter subscale of the Racial Identity Attitude Scale (RIAS-B; J. E. Helms & T. A. Parham, 1996), and 4 of the factors were negatively correlated with the Immersion/Emersion subscale of the RIAS-B. Four factors of the IROS were negatively correlated with all subscales and total scores of the African Self-Consciousness Scale (J. A. Baldwin & Y. R. Bell, 1985). These results provide some support of the validity of the IROS.  相似文献   
508.
Stressful events early in life can affect children’s mental health problems. Collecting valid and reliable information about children’s bad experiences is important for research and clinical purposes. This study aimed to (1) investigate whether mothers and children provide valid reports of bullying victimization, (2) examine the inter-rater reliability between the two informants, (3) test the predictive validity of their reports with children’s emotional and behavioral problems and (4) compare the genetic and environmental etiology of bullying victimization as reported by mothers and children. We assessed bullying victimization in the Environmental-Risk (E-Risk) Longitudinal Twin Study, a nationally-representative sample of 1,116 families with twins. We collected reports from mothers and children during private interviews, including detailed narratives. Findings showed that we can rely on mothers and children as informants of bullying victimization: both informants provided information which adhered to the definition of bullying as involving repeated hurtful actions between peers in the presence of a power imbalance. Although mothers and children modestly agreed with each other about who was bullied during primary and secondary school, reports of bullying victimization from both informants were similarly associated with children’s emotional and behavioral problems and provided similar estimates of genetic and environmental influences. Findings from this study suggest that collecting information from multiple informants is ideal to capture all instances of bullying victimization. However, in the absence of child self-reports, mothers can be considered as a viable alternative, and vice versa.  相似文献   
509.
Each year, an increasing number of children are born through surrogacy and thus lack a genetic and/or gestational link with their mother. This study examined the impact of surrogacy on mother-child relationships and children's psychological adjustment. Assessments of maternal positivity, maternal negativity, mother-child interaction, and child adjustment were administered to 32 surrogacy, 32 egg donation, and 54 natural conception families with a 7-year-old child. No differences were found for maternal negativity, maternal positivity, or child adjustment, although the surrogacy and egg donation families showed less positive mother-child interaction than the natural conception families. The findings suggest that both surrogacy and egg donation families function well in the early school years.  相似文献   
510.
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