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911.
An adapted alternating treatments design was used to compare the effectiveness of a taped-problems (TP) intervention with TP and an additional immediate assessment (TP + AIA) on the multiplication fluency of six fifth-grade students. During TP, the students listened to a tape playing a series of multiplication problems and answers three times. Students were instructed to try to beat the tape by writing each answer before they heard it on the tape. The interval between each problem and answer was varied as the problems were repeated. For the TP + AIA condition, immediately after completing TP, students completed an extra assessment sheet consisting of the same problems heard on the tape. Results showed increases in math-fact fluency across both treatment sets of problems (TP and TP + AIA) and a control set of problems. However, results varied across students and only two of the students showed meaningful gains when the TP was supplemented with the AIA. Implications and directions for future research are discussed.  相似文献   
912.
The category adjustment model (CAM) proposes that estimates of inexactly remembered stimuli are adjusted toward the central value of the category of which the stimuli are members. Adjusting estimates toward the average value of all category instances, properly weighted for memory uncertainty, maximizes the average accuracy of estimates. Thus far, the CAM has been tested only with symmetrical category distributions in which the central stimulus value is also the mean. We report two experiments using asymmetric (skewed) distributions in which there is more than one possible central value: one where the frequency distribution shifts over the course of time, and the other where the frequency distribution is skewed. In both cases, we find that people adjust estimates toward the category’s running mean, which is consistent with the CAM but not with alternative explanations for the adjustment of stimuli toward a category’s central value.  相似文献   
913.
Young children occasionally make scale errors – they attempt to fit their bodies into extremely small objects or attempt to fit a larger object into another, tiny, object. For example, a child might try to sit in a dollhouse-sized chair or try to stuff a large doll into it. Scale error research was originally motivated by parents' and researchers' informal accounts of these behaviors. However, scale errors have only been documented using laboratory procedures designed to promote their occurrence. To formally document the occurrence of scale errors in everyday settings, we posted a survey on the internet. Across two studies, participants reported many examples of everyday scale errors that are similar to those observed in our labs and were committed by children of the same age. These findings establish that scale errors occur in the course of children's daily lives, lending further support to the account that these behaviors stem from general aspects of visual processing.  相似文献   
914.
Infants are sensitive to biological motion, but do they recognize it as animate? As a first step towards answering this question, two experiments investigated whether 6‐month‐olds selectively attribute goals to shapes moving like animals. We habituated infants to a square moving towards one of two targets. When target locations were switched, infants reacted more to movement towards a new goal than a new location – but only if the square moved non‐rigidly and rhythmically, in a schematic version of bio‐mechanical movement older observers describe as animal‐like ( Michotte, 1963 ). Goal attribution was specific to schematic animal motion: It did not occur if the square moved rigidly with the same rhythm as the animate stimulus, or if the square had the same amount of non‐rigid deformation, but in an inanimate configuration. The data would seem to show that perception of schematic animal motion is linked to a system for psychological reasoning from infancy. This in turn suggests that 6‐month‐olds may already interpret biological motion as animate.  相似文献   
915.
Previous research findings have linked caregiver deprivation and emotional neglect with sensitivity to threatening cues. The present preliminary study investigated whether dysfunctions of the medial temporal lobe could underlie these associations. Using fMRI, we measured medial temporal lobe responses to emotional faces (angry, fearful, happy, neutral) among 30 youths. Eleven of the youths had a history of caregiver deprivation and emotional neglect. Attention states (i.e., attention to anger, fear, or physical attributes, or passive viewing) were systematically manipulated. Relative to comparison youths, youths with a history of caregiver deprivation and emotional neglect showed significantly greater left amygdala and left anterior hippocampus activation during the processing of threatening information. To our knowledge, these findings are the first to demonstrate altered medial temporal lobe function during the processing of threat cues in youths with a history of caregiver deprivation and emotional neglect.  相似文献   
916.
Association studies of the serotonin transporter promoter polymorphism (5-HTTLPR) and negative emotionality (NE) are inconclusive. However, emerging evidence suggests that the association between this polymorphism and NE may be influenced by levels of another temperament trait, positive emotionality (PE). Therefore, this study examined whether the association between the 5-HTTLPR and NE was moderated by PE. A community sample of 413 three-year-old children completed a standardized battery of laboratory tasks designed to tap temperamental emotionality. Children were also genotyped for the 5-HTTLPR. No direct association between 5-HTTLPR genotype and NE was found. However, the interaction of child PE and NE predicted 5-HTTLPR genotype. Furthermore, children with a short allele who were also low in PE had significantly greater NE than children without a short allele or children with high PE. Our findings suggest that the short allele of the 5-HTTLPR is associated with NE only in the context of low PE. Inconsistent links between NE and this gene in previous research may stem from the failure to consider other temperament traits that moderate associations.  相似文献   
917.
918.
Body dissatisfaction in women in the United States is common. We explored how women from various racial and ethnic groups used figural stimuli by exploring differences in current and preferred silhouette, and their discrepancy. We surveyed 4023 women aged 25–45 in an online investigation. Participants were identified using a national quota-sampling procedure. Asian women chose a smaller silhouette to represent their current body size, which did not remain significant after adjusting for self-reported BMI. After controlling for BMI, African American women selected a smaller silhouette than White women to represent their current size. Both African American and women reporting “Other” race preferred larger silhouettes than White women even after controlling for BMI. The discrepancy score revealed lower body dissatisfaction among African American than White women. Understanding factors that promote body satisfaction differentially across racial and ethnic groups could become a tool in appropriately tailored interventions designed to prevent eating disorders.  相似文献   
919.
Medical images constitute a core portion of the information a physician utilizes to render diagnostic and treatment decisions. At a fundamental level, this diagnostic process involves two basic processes: visually inspecting the image (visual perception) and rendering an interpretation (cognition). The likelihood of error in the interpretation of medical images is, unfortunately, not negligible. Errors do occur, and patients’ lives are impacted, underscoring our need to understand how physicians interact with the information in an image during the interpretation process. With improved understanding, we can develop ways to further improve decision making and, thus, to improve patient care. The science of medical image perception is dedicated to understanding and improving the clinical interpretation process.  相似文献   
920.
Women are becoming infected with HIV via heterosexual activity at an accelerating rate, both in the United States and globally. Although a number of evaluations of behavioral risk-reduction interventions for women have been reported, many suffer from methodological problems that weaken confidence in their findings, and furthermore it is clear that many women are unable to respond to the interventions that have been tested. Most women infected through heterosexual activity are infected by their primary partner, yet achieving consistent condom use with this partner can be highly challenging for women. The present article presents recent work and innovative ideas for intervention strategies that may be more feasible, and thus more effective, for women at risk for HIV infection by their primary male partner.  相似文献   
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