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941.
We evaluated the effects of feedback and instruction on resident physician performance during developmental surveillance of infants at 2-month preventive care visits. Baseline data were obtained by videotaping 3 residents while they performed the physical and developmental exam components. Training consisted of individualized feedback and a brief instructional module, after which the residents were again videotaped while they performed preventive care visits. All 3 residents showed improved performance following training.  相似文献   
942.
Can false memories have a positive consequence on human cognition? In two experiments, we investigated whether false memories could prime insight problem-solving tasks. Children and adults were asked to solve compound remote associate task (CRAT) problems, half of which had been primed by the presentation of Deese/Roediger-McDermott (DRM) lists whose critical lures were also the solutions to the problems. In Experiment 1, the results showed that regardless of age, when the critical lure was falsely recalled, CRAT problems were solved more often and significantly faster than problems that were not primed by a DRM list. When the critical lure was not falsely recalled, CRAT problem solution rates and times were no different from when there was no DRM priming. In Experiment 2, without an intervening recall test, children and adults still exhibited higher solution rates and faster solution times to CRAT problems that were primed than to those that were not primed. This latter result shows that priming occurred as a result of false memory generation at encoding and not at retrieval during the recall test. Together, these findings demonstrate that when false memories are generated at encoding, they can prime solutions to insight-based problems in both children and adults.  相似文献   
943.
Being ostracized can be a painful and distressing experience and can lead to subsequent aggression by the victim. However, it is unknown whether watching someone else be ostracized either in real life or on television is similarly distressing. The purpose of the current study was to examine what type of distress (if any) is induced after viewing ostracism on television. The study consisted of 50 participants, half who viewed a movie clip containing ostracism and half who viewed a control clip. Physiological and self-report data revealed that viewing ostracism was distressing to participants. In particular, participants who viewed the ostracism clip reported a lower sense of belonging, self esteem, and mood, and a greater increase in heart rate and skin conductivity than those who viewed the control clip.  相似文献   
944.
It has long been understood that food deliveries may act as signals of future food location, and not only as strengtheners of prefood responding as the law of effect suggests. Recent research has taken this idea further—the main effect of food deliveries, or other “reinforcers”, may be signaling rather than strengthening. The present experiment investigated the ability of food deliveries to signal food contingencies across time after food. In Phase 1, the next food delivery was always equally likely to be arranged for a left‐ or a right‐key response. Conditions were arranged such that the next food delivery was likely to occur either sooner on the left (or right) key, or sooner on the just‐productive (or not‐just‐productive) key. In Phase 2, similar contingencies were arranged, but the last‐food location was signaled by a red keylight. Preference, measured in 2‐s bins across interfood intervals, was jointly controlled by the likely time and location of the next food delivery. In Phase 1, when any food delivery signaled a likely sooner next food delivery on a particular key, postfood preference was strongly toward that key, and moved toward the other key across the interreinforcer interval. In other conditions in which food delivery on the two keys signaled different subsequent contingencies, postfood preference was less extreme, and quickly moved toward indifference. In Phase 2, in all three conditions, initial preference was strongly toward the likely‐sooner food key, and moved to the other key across the interfood interval. In both phases, at a more extended level of analysis, sequences of same‐key food deliveries caused a small increase in preference for the just‐productive key, suggesting the presence of a “reinforcement effect”, albeit one that was very small.  相似文献   
945.
Many studies have examined the accuracy of predictions of future memory performance solicited through judgments of learning (JOLs). Among the most robust findings in this literature is that delaying predictions serves to substantially increase the relative accuracy of JOLs compared with soliciting JOLs immediately after study, a finding termed the delayed JOL effect. The meta-analyses reported in the current study examined the predominant theoretical accounts as well as potential moderators of the delayed JOL effect. The first meta-analysis examined the relative accuracy of delayed compared with immediate JOLs across 4,554 participants (112 effect sizes) through gamma correlations between JOLs and memory accuracy. Those data showed that delaying JOLs leads to robust benefits to relative accuracy (g = 0.93). The second meta-analysis examined memory performance for delayed compared with immediate JOLs across 3,807 participants (98 effect sizes). Those data showed that delayed JOLs result in a modest but reliable benefit for memory performance relative to immediate JOLs (g = 0.08). Findings from these meta-analyses are well accommodated by theories suggesting that delayed JOL accuracy reflects access to more diagnostic information from long-term memory rather than being a by-product of a retrieval opportunity. However, these data also suggest that theories proposing that the delayed JOL effect results from a memorial benefit or the match between the cues available for JOLs and those available at test may also provide viable explanatory mechanisms necessary for a comprehensive account.  相似文献   
946.
947.
Previous research has linked higher levels of hopelessness about one's future to violent behavior during adolescence; however, little is known about this relationship over time for adolescents. Using growth curve modeling, we tested the association between future orientation and violent behavior across the high school years of adolescence in a sample of African American youth (n = 681). Variation based on demographic characteristics (i.e., sex, SES, previous violence) was explored. At baseline, differences in violent behavior varied by demographic characteristics. Overall, violent behavior decreased with age. Higher levels of future orientation were associated with greater decreases in violent behavior over time. Demographic characteristics were not associated with change in violent behavior overtime. Our findings suggest that future orientation can act as a promotive factor for at risk African American youth. Interventions that help support the development of future goals and aspirations could play a vital role in violence prevention efforts.  相似文献   
948.
In much of the youth empowerment literature, researchers focus on the relationship between youth and adults involved in empowerment programs while neglecting the broader social framework in which these relationships and the program itself functions. Utilizing an ecological model, the current research examines the tensions that surfaced in attempts to create an empowering setting in an after-school PAR program with fifth-graders. Challenging assumptions about youth, structural challenges, and conflicting theories of change are highlighted. Results examine the role of sociocultural context as PAR researchers attempt to create a setting in which students gain skills to become change agents within their school. The study suggests that youth empowerment is a context dependent process that requires attention to a multiplicity of factors that influence possibilities for empowerment via second order change.  相似文献   
949.
This study investigated the extent to which trait anxiety and state anxiety in response to stress are associated with the cortisol awakening response (CAR).Fifty-one healthy participants were recruited. State anxiety measures were taken in anticipation of and during a laboratory stressor. Salivary cortisol levels were measured immediately upon awakening (at 0, 15, 30, and 45 min) on two consecutive mornings. Cortisol awakening response was assessed by the area under the curve with respect to zero (AUCG).The magnitude of the CAR was found to be negatively associated with both trait anxiety and anticipatory anxiety. Moreover, regression analysis showed that the effects of trait anxiety on the AUCG were mediated by anticipatory anxiety.These results suggest that the CAR is influenced by trait anxiety. Moreover, the effect of trait anxiety on the CAR seems to operate by impacting on psychological stress reactivity (i.e., anticipatory anxiety).  相似文献   
950.
The Trail-Making Test (TMT) is a widely used neuropsychological measure that assesses visuomotor abilities and cognitive flexibility. For the TMT-A condition participants are required to locate and connect numbers (i.e. 1-2-3…) while in the TMT-B condition participants perform the set-shifting task of locating and connecting numbers and letters (i.e. 1-A-2-B…). The TMT-B condition has shown impairments in many clinical populations, particularly schizophrenia patients, but the neurobiological underpinning of the task can be difficult to discern given pragmatic obstacles in adapting the task for neuroimaging. In a behavioural testing experiment we demonstrated a close correspondence between performance on the standard TMT and a novel, computer programmed adaptation of the TMT (pcTMT). The pcTMT was designed for functional magnetic resonance imaging (fMRI) administration and neuroimaging data for this task were obtained in. A whole brain analysis revealed significantly greater activation during the pcTMT-B relative to the pcTMT-A in right inferior/middle frontal cortices, right precentral gyrus, left angular gyrus/left middle temporal gyrus. These results identify the regions that most likely underlie cognitive flexibility during the TMT and are candidate regions underlying the impairment of groups with poor set-shifting abilities.  相似文献   
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