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921.
Yawning may serve both social and nonsocial functions. When budgerigars (Melopsittacus undulatus) are briefly held, simulating capture by a predator, the temporal pattern of yawning changes. When this species is observed in a naturalistic setting (undisturbed flock), yawning and also stretching, a related behavior, are mildly contagious. On the basis of these findings, we hypothesized that a stressful event would be followed by the clustering of these behaviors in a group of birds, which may be facilitated both by a standard pattern of responding to a startling stressor and also contagion. In this study, we measured yawning and stretching in 4-bird groups following a nonspecific stressor (loud white noise) for a period of 1 hr, determining whether auditory disturbances alter the timing and frequency of these behaviors. Our results show that stretching, and to a lesser degree yawning, were nonrandomly clumped in time following the auditory disturbances, indicating that the temporal clustering is sensitive to, and enhanced by, environmental stressors while in small groups. No decrease in yawning such as found after handling stress was observed immediately after the loud noise but a similar increase in yawning 20 min after was observed. Future research is required to tease apart the roles of behavioral contagion and a time-setting effect following a startle in this species. This research is of interest because of the potential role that temporal clumping of yawning and stretching could play in both the collective detection of, and response to, local disturbances or predation threats.  相似文献   
922.
Students who do not get along with their peers are at elevated risk for academic disengagement and school failure. Research has predominantly focused on factors within such children that contribute to their peer problems. This study considers whether teacher practices also predict social preference for children in that classroom. Participants were 26 elementary school teachers and 490 students in their classrooms followed for one school year. Results suggested that teachers who favored the most academically talented students in the fall had classrooms where children had lower average social preference in the spring after statistical control of children's fall social preference and externalizing behavior problems. Teachers who demonstrated emotionally supportive relationships with students in the fall had classrooms where children had greater possibility of changing their social preference from fall to spring. Although children with high externalizing behaviors tended to experience declining social preference over the course of the school year, teachers' learner-centered practices attenuated this progression. However, teachers' favoring of the most academically talented accentuated the negative relation between externalizing behaviors and social preference. Implications for school psychology practitioners are discussed.  相似文献   
923.
The sunk cost effect occurs when an individual persists following an initial investment, even when persisting is costly in the long run. The current study used a laboratory model of the sunk cost effect. Two response alternatives were available: Pigeons could persist by responding on a schedule key with mixed ratio requirements, or escape by responding on a second key. In Experiment 1, mean response requirements for persistence and escape were varied across conditions. Pigeons persisted (committing the sunk cost error) when persisting increased the mean response requirement only slightly but not when persisting was sufficiently nonoptimal. Experiment 2 explored more systematically combinations of ratios and probabilities assigned to the schedule key. Persistence varied with the ratio of the mean global response requirements for persistence and escape. In Experiment 3, transitions between ratios were signaled. This reduced nonoptimal persistence, and produced some instances of a reverse sunk cost error--escaping when persistence was optimal. In Experiment 4, it was optimal to escape after the second-smallest ratio ever presented. Pigeons escaped at approximately the optimal juncture, especially in conditions with added signals. Overall, this series of experiments suggests that the sunk cost error may arise in part because persistence is the default behavioral strategy in situations where the contingencies for escape and persistence are insufficiently disparate and/or it is relatively difficult to discriminate when to escape. The study also demonstrates the utility of animal models of complex decision making situations.  相似文献   
924.
This research note describes the use of latent class analysis to examine how three dimensions of religiosity—the importance of religion (religious salience), attendance at religious services, and frequency of prayer—cluster together to form unique profiles. Building upon recent research identifying different profiles of religiosity at the level of the individual, we used data from the National Longitudinal Study of Adolescent Health to identify dyadic profiles of religious concordance or discordance between 14,202 adolescents and their mothers. We identified five profiles: one concordant (27% of sample), two discordant (25% of sample), and two of mixed concordance/discordance (49%). The profiles distinguish between various levels of adolescent/mother relations, suggesting that they may represent distinct family dynamics. They also distinguish between several variables (race, adolescent age, geographical region) in predictable ways, providing additional demonstration of the categories’ meaningfulness.  相似文献   
925.
In two experiments, we examined the role of discrepancy on readers’ text processing of and memory for the sources of brief news reports. Each story included two assertions that were attributed to different sources. We manipulated whether the second assertion was either discrepant or consistent with the first assertion. On the basis of the discrepancy-induced source comprehension (D-ISC) assumption, we predicted that discrepant stories would promote deeper processing and better memory for the sources conveying the messages, as compared to consistent stories. As predicted, readers mentioned more sources in summaries of discrepant stories, recalled more sources, made more fixations, and displayed longer gaze times in source areas when reading discrepant than when reading consistent stories. In Experiment 2, we found enhanced memory for source–content links for discrepant stories even when intersentential connectors were absent, and regardless of the reading goals. Discussion was focused on discrepancies as one mechanism by which readers are prompted to encode source–content links more deeply, as a method of integrating disparate pieces of information into a coherent mental representation of a text.  相似文献   
926.
Both the recognition-without-identification (RWI) and feeling-of-knowing (FOK) paradigms attempt to tap participants?? sense about a target that is inaccessible. In the case of RWI, participants judge the likelihood that the inaccessible target was studied. In the case of FOKs, participants judge the likelihood that the inaccessible target will be recognized at a later point in time. The present study compared the two using a hybrid paradigm. The patterns of responding differed depending on whether the judgment was of the RWI type or the FOK type. For the former, ratings were significantly higher for studied than for unstudied inaccessible targets (the typical RWI effect). For the latter, ratings were significantly lower for studied than for unstudied inaccessible targets (a reversal of the usual RWI effect). Similarity of the targets and distractors diminished the usual RWI effect, but not its reversal in the FOK situation, suggesting that the bases of the two effects differ. A potential explanation is that when participants judge whether an inaccessible target was presented earlier, they are oriented toward relying on cue familiarity, which should be greater for cues of studied targets, whereas when they judge whether they will recognize an inaccessible target later on, they are oriented toward relying on the accessibility of information, which is greater in the unstudied condition, due to the lack of priming of the targets.  相似文献   
927.
928.
Before performing neurosurgery, an exhaustive presurgical assessment is required, usually including an investigation of language cerebral lateralization. Among the available procedures, the intracarotid amobarbital test (IAT) was formerly the most widely used. However, this procedure has many limitations: it is invasive and potentially traumatic, especially for children. To overcome these limitations, neuroimaging techniques such as functional magnetic resonance imaging (fMRI) have been used. Again, these methods are difficult to use with children, who must remain motionless during data acquisition. Functional near-infrared spectroscopy (fNIRS) is a noninvasive functional imaging technique that is easily applied to pediatric and cognitively limited patients. It has been used recently in epileptic children for presurgical assessment of expressive and receptive language brain lateralization. The aim of this review is to present the contribution of fNIRS to the presurgical assessment of language function in children with neurological diseases.  相似文献   
929.
PurposeThe purpose of this study was to compare two welfare outcome measures, willingness to pay (WTP) and quality adjusted life years (QALYs) gained, to measure outcomes in stuttering.MethodSeventy-eight adult participants (74 nonstuttering and 4 persons with stuttering) completed one face-to-face structured interview regarding how much they would be willing to pay to alleviate severe stuttering in three interventions of varying impact. These data were compared with QALYs gained as calculated from time trade off (TTO) and standard gamble (SG) data.ResultsMean (median) WTP bids ranged from US$ 16,875 (8000), for an intervention resulting in improvement from severe stuttering to mild stuttering, to US$ 41,844 (10,000) for an intervention resulting in a cure of severe stuttering. These data were consistent with mean changes in QALYs for the same stuttering interventions ranging from 2.19 (using SG) to 18.42 (using TTO).ConclusionsThis study presents the first published WTP and QALY data for stuttering. Results were consistent with previous cost-of-illness data for stuttering. Both WTP and QALY measures were able to quantify the reduction in quality of life that occurs in stuttering, and both can be used to compare the gains that might be achieved by different interventions. It is widely believed that stuttering can cause reduced quality of life for some speakers; the introduction into this field of standardized metrics for measuring quality of life is a necessary step for transparently weighing the costs and consequences of stuttering interventions in economic analyses.Educational objectives: The reader will be able to (a) describe the underlying theoretical foundations for willingness to pay and quality adjusted life years, (b) describe the application of willingness to pay and quality adjusted life years for use in economic analyses, (c) compare and contrast the value of willingness to pay and quality adjusted life years in measuring the impact of stuttering treatment on quality of life, (d) interpret quality adjusted life years, and (e) interpret willingness to pay data.  相似文献   
930.
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