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821.
Space advocates, presidents, and NASA administrators have talked for decades about sending people back to the Moon and on to Mars, to stay. Neither funding nor public support has materialized. Billionaire Elon Musk has declared his intent to establish a human colony on Mars, drawing much media attention. Here Linda Billings argues that it would be unethical to contaminate a potentially habitable planet for further scientific exploration and immoral to transport a tiny, non-representative, subset of humanity—made up of people who could afford to spend hundreds of thousands to millions of dollars on the trip—to live on Mars.  相似文献   
822.
The authors examined the dimensionality and psychometric properties of the Multigroup Ethnic Identity Measure (MEIM) among Black South African adolescents (ages = 13–14; 52% female) representing several ethnic groups (Ndebele, Pedi, Sotho, Swati, Tsonga, Tswana, Venda, Xhosa, Zulu) and evaluated the measure for differential item functioning primarily among four ethnic groups (Sotho, Tswana, Xhosa, and Zulu). Results indicated that a two-dimensional model best represented the data, reflecting ethnic search/clarity and ethnic affirmations. Subsequently, we evaluated the equivalence of the MEIM among the four South African ethnic groups and a sample of African American adolescents (Mage = 15.57 years; SD = 1.22; 51% female). Further analyses revealed that configural and metric models were excellent across the four South African ethnic groups and the African American group. However, scalar invariance (i.e., intercept) was not found; the item intercepts were different for the South African ethnic groups and African Americans. Findings are discussed with consideration for conducting research on ethnic identity among youth in South Africa.  相似文献   
823.
824.
Infants' perception of faces becomes attuned to the environment during the first year of life. However, the mechanisms that underpin perceptual narrowing for faces are only poorly understood. Considering the developmental similarities seen in perceptual narrowing for faces and speech and the role that statistical learning has been shown to play for speech, the current study examined whether and how learning from distributional information impacts face identity discrimination. We familiarized 6.5‐month‐old infants with exemplars of female faces taken from a morphed continuum going from one identity to another. Using event‐related brain potentials (ERPs), we show that only infants who were familiarized with a bimodal frequency distribution, but not infants familiarized with a unimodal frequency distribution, discriminated between identities. These results are the first to demonstrate the influence of probabilistic information on infants' face identity discrimination, suggesting that statistical learning contributes to perceptual attunement for both faces and language.  相似文献   
825.
In executing purposeful actions, adults select sufficient and necessary limbs. But infants often move goal‐irrelevant limbs, suggesting a developmental process of motor specialization. Two experiments with 9‐ and 12‐month‐olds revealed gradual decreases in extraneous movements in non‐acting limbs during unimanual actions. In Experiment 1, 9‐month‐olds produced more extraneous movements in the non‐acting hand/arm and feet/legs than 12‐month‐olds. In Experiment 2, analysis of the spatiotemporal dynamics of infants’ movements revealed developmental declines in the spatiotemporal coupling of movements between acting and non‐acting arms. We also showed that the degree of specialization in infants’ unimanual actions is associated with individual differences in motor experience and visual attention, indicating the experience‐dependent and broad functional nature of these developmental changes. Our study provides important new insights into motor development: as in cognitive domains, motor behaviours are initially broadly tuned to their goal, becoming progressively specialized during the first year of life.  相似文献   
826.
Faces are adaptively coded relative to visual norms that are updated by experience, and this adaptive coding is linked to face recognition ability. Here we investigated whether adaptive coding of faces is disrupted in individuals (adolescents and adults) who experience face recognition difficulties following visual deprivation from congenital cataracts in infancy. We measured adaptive coding using face identity aftereffects, where smaller aftereffects indicate less adaptive updating of face‐coding mechanisms by experience. We also examined whether the aftereffects increase with adaptor identity strength, consistent with norm‐based coding of identity, as in typical populations, or whether they show a different pattern indicating some more fundamental disruption of face‐coding mechanisms. Cataract‐reversal patients showed significantly smaller face identity aftereffects than did controls (Experiments 1 and 2). However, their aftereffects increased significantly with adaptor strength, consistent with norm‐based coding (Experiment 2). Thus we found reduced adaptability but no fundamental disruption of norm‐based face‐coding mechanisms in cataract‐reversal patients. Our results suggest that early visual experience is important for the normal development of adaptive face‐coding mechanisms.  相似文献   
827.
Can bilingual exposure impact children's neural circuitry for learning to read? To answer this question, we investigated the brain bases of morphological awareness, one of the key spoken language abilities for learning to read in English and Chinese. Bilingual Chinese‐English and monolingual English children (= 22, ages 7–12) completed morphological tasks that best characterize each of their languages: compound morphology in Chinese (e.g. basket + ball = basketball) and derivational morphology in English (e.g. re + do = redo). In contrast to monolinguals, bilinguals showed greater activation in the left middle temporal region, suggesting that bilingual exposure to Chinese impacts the functionality of brain regions supporting semantic abilities. Similar to monolinguals, bilinguals showed greater activation in the left inferior frontal region [BA 45] in English than Chinese, suggesting that young bilinguals form language‐specific neural representations. The findings offer new insights to inform bilingual and cross‐linguistic models of language and literacy acquisition.  相似文献   
828.
Past research has shown that young monolingual children exhibit language‐based social biases: they prefer native language to foreign language speakers. The current research investigated how children's language preferences are influenced by their own bilingualism and by a speaker's bilingualism. Monolingual and bilingual 4‐ to 6‐year‐olds heard pairs of adults (a monolingual and a bilingual, or two monolinguals) and chose the person with whom they wanted to be friends. Whether they were from a largely monolingual or a largely bilingual community, monolingual children preferred monolingual to bilingual speakers, and native language to foreign language speakers. In contrast, bilingual children showed similar affiliation with monolingual and bilingual speakers, as well as for monolingual speakers using their dominant versus non‐dominant language. Exploratory analyses showed that individual bilinguals displayed idiosyncratic patterns of preference. These results reveal that language‐based preferences emerge from a complex interaction of factors, including preference for in‐group members, avoidance of out‐group members, and characteristics of the child as they relate to the status of the languages within the community. Moreover, these results have implications for bilingual children's social acceptance by their peers.  相似文献   
829.
This conversation between the editors of Teaching Theology and Religion and Joanne Maguire Robinson continues an occasional series of interviews that has previously featured Jonathan Z. Smith, Stephen Prothero, Mary Pierce Brosmer, and Mary Elizabeth Mullino Moore. The exchange takes as its point of departure the teaching statement that Professor Robinson produced in support of her candidacy for the American Academy of Religion's Excellence in Teaching Award. Issues addressed include the impact of institutional context on one's teaching, teaching the humanities in universities that are ever more focused on job training, making the transition from a graduate program focused on research to teaching undergraduates who are unlikely to take even a second course in the study of religion, and ways in which women are challenged to navigate multiple responsibilities while striving to make their way in a male‐dominated academy.  相似文献   
830.
Background and Objectives: Social stress and associated coping responses can profoundly influence women’s stress physiology and health. Implicit social attentional biases can also influence psychological and physiological stress responses. The purpose of this study was to explore whether a coping style characterized by greater use of social support predicts indices of cortisol activity in laboratory and daily life contexts among female university students. We hypothesized that the relation of this coping style to cortisol activity would be moderated by women’s attentional biases.

Methods: Seventy-four women (Mage?=?19.44, range: 17.8–27.8, 64% White) completed an interpersonal stress task and an attentional bias task in the lab, along with a self-report coping inventory. Participants provided five saliva samples during the lab protocol, followed by three saliva samples per day for three consecutive weekdays. Outcome measures included cortisol response to lab tasks (AUCg), diurnal cortisol slope, diurnal AUCg, and cortisol awakening response (CARi).

Results: A coping style characterized by greater use of social support predicted lower lab AUCg and lower, flatter average diurnal cortisol slope for women with attentional avoidance compared to women with attentional vigilance (ps?<?.05).

Conclusions: Responding to stress by using social support is linked to lower cortisol responses to social stress and diurnal cortisol activity for women with implicit avoidance of social threat cues.  相似文献   
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