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71.
Over a three-semester period in a large undergraduate human development course, students were assigned to 5–7 member groups to work together in preparing for an exam in one of the five content units in the course. Their exam performance was tracked over three units: a baseline unit in which students worked only individually, a unit in which they worked in cooperative teams, and a follow-up unit in which the formal cooperative team structure was removed. Three different bonus-credit contingencies were used in the cooperative learning unit across the three semesters: (a) awarding full bonus credit to each individual in the group if the group as a whole improved its exam performance by the specified amount, (b) awarding partial bonus credit to each individual in the group if the group as a whole improved it exam performance by the specified amount and full bonus credit to each individual who also improved by the specified amount, and (c) awarding full bonus credit to an individual in the group if both the group and the individual improved exam performance by the specified amount. The three contingencies produced somewhat similar patterns of change for low and average performers, but the high performers fared better under the last two contingencies than under the group-only contingency.  相似文献   
72.
Following terror management theory, the authors suggest women's striving to attain a thin physique is fueled in part by existential concerns. In three studies, women restricted consumption of a nutritious but fattening food in response to reminders of mortality (mortality salience; MS). When conducted in private (Study 1), this effect was found among women but not men; when replicated in a group setting in which social comparison was likely (Studies 2 and 3), only women who were relatively less successful attaining the thin ideal (i.e., high body mass index; BMI) restricted eating after MS. In Study 3, MS caused high BMI women to perceive themselves as more discrepant from their ideal thinness; this perceived failure mediated the effects of MS and BMI on eating behavior. Findings are discussed from a self-regulatory framework, which considered in the context of pressures for women to be thin, can shed light on health risk behavior.  相似文献   
73.
It is widely recognized that people sometimes use theory-of-mind judgments in moral cognition. A series of recent studies shows that the connection can also work in the opposite direction: moral judgments can sometimes be used in theory-of-mind cognition. Thus, there appear to be cases in which people's moral judgments actually serve as input to the process underlying their application of theory-of-mind concepts.  相似文献   
74.
Bottlenose dolphins are unusual among non-human mammals in their ability to learn new sounds. This study investigates the importance of vocal learning in the development of dolphin signature whistles and the influence of social interactions on that process. We used focal animal behavioral follows to observe six calves in Sarasota Bay, Fla., recording their social associations during their first summer, and their signature whistles during their second. The signature whistles of five calves were determined. Using dynamic time warping (DTW) of frequency contours, the calves signature whistles were compared to the signature whistles of several sets of dolphins: their own associates, the other calves associates, Tampa Bay dolphins, and captive dolphins. Whistles were considered similar if their DTW similarity score was greater than those of 95% of the whistle comparisons. Association was defined primarily in terms of time within 50 m of the mother/calf pair. On average, there were six dolphins with signature whistles similar to the signature whistles of each of the calves. These were significantly more likely to be Sarasota Bay resident dolphins than non-Sarasota dolphins, and (though not significantly) more likely to be dolphins that were within 50 m of the mother and calf less than 5% of the time. These results suggest that calves may model their signature whistles on the signature whistles of members of their community, possibly community members with whom they associate only rarely.  相似文献   
75.
Some children living with life-shortening medical conditions may wish to attend school without the threat of having resuscitation attempted in the event of cardiopulmonary arrest on the school premises. Despite recent attention to in-school do-not-attempt-resuscitation (DNAR) orders, no assessment of state laws or school policies has yet been made. We therefore sought to survey a national sample of prominent school districts and situate their policies in the context of relevant state laws. Most (80%) school districts sampled did not have policies, regulations, or protocols for dealing with student DNARs. A similar majority (76%) either would not honor student DNARs or were uncertain about whether they could. Frequent contradictions between school policies and state laws also exist. Consequently, children living with life-shortening conditions who have DNARs may not have these orders honored if cardiopulmonary arrest were to occur on school premises. Coordinated efforts are needed to harmonize school district, state, and federal approaches in order to support children and families' right to have important medical decisions honored.  相似文献   
76.
This research examined whether stereotype vulnerability-the tendency to expect, perceive, and be influenced by negative stereotypes about one's social category-is associated with uncertainty about one's academic self-knowledge in two important ways. We predicted that stereotype-vulnerable African American students would (a) know less about how much they know than less vulnerable students do and (b) have unstable academic efficacy. In Study 1, Black and White participants took a verbal test and indicated the probability that each of their answers was correct. As expected, stereotype-vulnerable Black participants were more miscalibrated than other participants. In Study 2, participants completed measures of self-efficacy twice daily for 8 days. Also as expected, the academic efficacy of stereotype-vulnerable Blacks fluctuated more-and more extremely-than that of other participants. The results suggest that, in addition to undermining intellectual performance, stigma interferes with academic self-knowledge.  相似文献   
77.
Infants' expressions of discrete emotions were coded during the more stressful episodes (4 through 8) of the Strange Situation at 13 and 18 months. The data showed a significant decrease in full-face expressions (more complex configurations of movements) and a significant increase in component expressions (simpler and more constrained patterns of movements). The authors interpreted this trend as a developmental change toward more regulated and less intense emotions. Consistent with this view, the aggregate index of infants' full-face negative emotion expressions, interpreted as reflecting relatively unregulated intense emotions, correlated significantly with maternal ratings of difficult temperament. The authors discuss alternative interpretations of the findings in terms of changes in reactivity/arousability and the emerging capacity for self-regulation.  相似文献   
78.
In order to examine the concurrent and criterion validity of the questionnaire version of the Eating Disorders Examination (EDE-Q), self-report and interview formats were administered to a community sample of women aged 18-45 (n = 208). Correlations between EDE-Q and EDE subscales ranged from 0.68 for Eating Concern to 0.78 for Shape Concern. Scores on the EDE-Q were significantly higher than those of the EDE for all subscales, with the mean difference ranging from 0.25 for Restraint to 0.85 for Shape Concern. Frequency of both objective bulimic episodes (OBEs) and subjective bulimic episodes (SBEs) was significantly correlated between measures. Chance-corrected agreement between EDE-Q and EDE ratings of the presence of OBEs was fair, while that for SBEs was poor. Receiver operating characteristic (ROC) analysis, based on a sample of 13 cases, indicated that a score of 2.3 on the global scale of the EDE-Q in conjunction with the occurrence of any OBEs and/or use of exercise as a means of weight control, yielded optimal validity coefficients (sensitivity = 0.83, specificity = 0.96, positive predictive value = 0.56). A stepwise discriminant function analysis yielded eight EDE-Q items which best distinguished cases from non-cases, including frequency of OBEs, use of exercise as a means of weight control, use of self-induced vomiting, use of laxatives and guilt about eating. The EDE-Q has good concurrent validity and acceptable criterion validity. The measure appears well-suited to use in prospective epidemiological studies.  相似文献   
79.
80.
In several recent studies, saccadic eye movements were found to be influenced by concurrent reaching movements. The authors investigated whether that influence originates in limb kinematic or kinetic signals. To dissociate those 2 possibilities, the authors required participants (N = 6) to generate pointing movements with a mass that either resisted or assisted limb motion. With practice, participants were able to generate pointing responses with very similar kinematics but whose kinetics varied in a systematic manner. The results showed that saccadic output was altered by the amount of force required to move the arm, consistent with an influence from limb kinetic signals. Because the interaction occurred before the pointing response began, the authors conclude that a predictive signal related to limb kinetics modulates saccadic output during tasks requiring eye-hand coordination.  相似文献   
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