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171.
An Examination of Potential Misclassification of Army Suicides: Results from the Army Study to Assess Risk and Resilience in Servicemembers 下载免费PDF全文
Kenneth L. Cox MD MPH Matthew K. Nock PhD Quinn M. Biggs PhD MPH Jennifer Bornemann MSSW Lisa J. Colpe PhD MPH Catherine L. Dempsey PhD MPH Steven G. Heeringa PhD James E. McCarroll PhD MPH Tsz Hin Ng MPH Michael Schoenbaum PhD Robert J. Ursano MD Bailey G. Zhang MS David M. Benedek MD the Army STARRS Collaborators 《Suicide & life-threatening behavior》2017,47(3):257-265
Debate continues about the accuracy of military suicide reporting due to concerns that some suicides may be classified as accidents to minimize stigma and ensure survivor benefits. We systematically reviewed records for 998 active duty Army deaths (510 suicides; 488 accident, homicide, and undetermined deaths; 2005‐2009) and, using research criteria, reclassified 8.2% of the nonsuicide cases to definite suicide (1), suicide probable (4), or suicide possible (35). The reclassification rate to definite suicide was only 0.2% (1/488). This low rate suggests that flagrant misclassification of Army deaths is uncommon and surveillance reports likely reflect the “true” population of Army suicides. 相似文献
172.
173.
Strategies in probabilistic categorization: results from a new way of analyzing performance 下载免费PDF全文
Meeter M Myers CE Shohamy D Hopkins RO Gluck MA 《Learning & memory (Cold Spring Harbor, N.Y.)》2006,13(2):230-239
The "Weather Prediction" task is a widely used task for investigating probabilistic category learning, in which various cues are probabilistically (but not perfectly) predictive of class membership. This means that a given combination of cues sometimes belongs to one class and sometimes to another. Prior studies showed that subjects can improve their performance with training, and that there is considerable individual variation in the strategies subjects use to approach this task. Here, we discuss a recently introduced analysis of probabilistic categorization, which attempts to identify the strategy followed by a participant. Monte Carlo simulations show that the analysis can, indeed, reliably identify such a strategy if it is used, and can identify switches from one strategy to another. Analysis of data from normal young adults shows that the fitted strategy can predict subsequent responses. Moreover, learning is shown to be highly nonlinear in probabilistic categorization. Analysis of performance of patients with dense memory impairments due to hippocampal damage shows that although these patients can change strategies, they are as likely to fall back to an inferior strategy as to move to more optimal ones. 相似文献
174.
Schatz J McClellan CB 《Mental retardation and developmental disabilities research reviews》2006,12(3):200-207
Sickle cell disease (SCD) is a blood disorder; however, the central nervous system (CNS) is one of the organs frequently affected by the disease. Brain disease can begin early in life and often leads to neurocognitive dysfunction. Approximately one-fourth to one-third of children with SCD have some form of CNS effects from the disease, which typically manifest as deficits in specific cognitive domains and academic difficulties. We discuss SCD as a neurodevelopmental disorder by reviewing the mechanisms of neurological morbidity in SCD, the timing of these mechanisms, the types of cognitive and behavioral morbidity that is typical, and the interaction of social-environmental context with disease processes. The impact of the disease on families shares many features similar to other neurodevelopmental disorders; however, social-environmental factors related to low socioeconomic status, worry and concerns about social stigma, and recurrent, unpredictable medical complications can be sources of relatively higher stress in SCD. Greater public awareness of the neurocognitive effects of SCD and their impact on child outcomes is a critical step toward improved treatment, adaptation to illness, and quality of life. 相似文献
175.
Costigan CL Bardina P Cauce AM Kim GK Latendresse SJ 《Cultural diversity & ethnic minority psychology》2006,12(4):710-724
Between-group and within-group differences in perceptions of behavior were examined among 74 Asian Americans and 111 European Americans. Participants rated videotaped interactions of Asian American mothers and daughters. Asian Americans, and a more homogeneous sample of Chinese Americans, perceived less maternal control and more reciprocity than did European Americans. Intra-cultural variations in perceptions were also evident, as within-group analyses revealed differences in perceptions based on the generational status of Asian Americans and the degree of multicultural experience of European Americans. Overall, findings suggest that perceptions of behavior are shaped as much by within-group differences in familiarity and experience with the target culture as by between-group differences in ethnicity. Implications for theories of child socialization, multicultural counseling, and observational research are discussed. 相似文献
176.
We presented bumblebees a spatial memory task similar to that used with other species (e.g., cats, dogs, and pigeons). In
some conditions we allowed for presence of scent marks in addition to placing local and global spatial cues in conflict. Bumblebees
(Bombus impatiens) were presented an array of artificial flowers within a flight cage, one flower offering reward (S+), while the others were
empty (S−). Bees were tested with empty flowers. In Experiment 1, flowers were either moved at the time of testing or not.
Bees returned to the flower in the same absolute position of the S+ (the flower-array-independent (FAI) position), even if
it was in the wrong position relative to the S− and even when new flower covers prevented the use of possible scent marks.
New flower covers (i.e., without possible scent marks) had the effect of lowering the frequency of probing behavior. In Experiment
2, the colony was moved between training and testing. Again, bees chose the flower in the FAI position of the S+, and not
the flower that would be chosen using strictly memory for a flight vector. Together, these experiments show that to locate
the S+ bees did not rely on scent marks nor the positions of the S−, though the S− were prominent objects close to the goal.
Also, bees selected environmental features to remember the position of the S+ instead of relying upon a purely egocentric
point of view. Similarities with honeybees and vertebrates are discussed, as well as possible encoding mechanisms. 相似文献
177.
Burack JA Flanagan T Peled T Sutton HM Zygmuntowicz C Manly JT 《Developmental psychology》2006,42(2):207-217
The primary goal of this study was to assess the ability of maltreated school-age children and adolescents to understand the thoughts, feelings, and points of view of others. Level of egocentrism and social perspective-taking coordination were assessed in a group of 49 maltreated and 49 demographically matched nonmaltreated children. Twenty-six elementary and 23 high school students in each group were individually interviewed and their responses to hypothetical interpersonal situations coded for egocentricity and level of perspective-taking ability. The findings revealed that maltreated children and adolescents were more egocentric and delayed in their social perspective-taking development than their nonmaltreated peers and that they reported lower levels of global self-worth. However, differences within the group of maltreated children and adolescents emerged with regard to negotiating novel relationships, as those with fewer internalizing or externalizing symptoms exhibited better skills in this area than their peers who displayed more symptoms. 相似文献
178.
Patients with schizophrenia have a substantial lifetime suicide risk, especially by violent means. Little published work exists on self-harm (SH) in this population. The goal of this study was to examine whether patients with schizophrenia were also more likely to self-harm in a violent manner. A retrospective analysis performed on method, motive, and suicidal intent in patients with schizophrenia (n = 50) and adjustment reaction (n = 138) who presented with SH over a 3-year period found that there was no significant difference between the two groups in terms of violence of method or suicidal intent. Presence of positive symptoms of schizophrenia was not significantly associated with use of a violent method. This study suggests that the expected pattern of violent SH in schizophrenia is inaccurate and for the majority the acts are of a similar nature to those seen in adjustment reactions. 相似文献
179.
Expertise in recognizing facial identity, and, in particular, sensitivity to subtle differences in the spacing among facial features, improves into adolescence. To assess the influence of experience, we tested adults and 8-year-olds with faces differing only in the spacing of facial features. Stimuli were human adult, human 8-year-old, and monkey faces. We show that adults' expertise is shaped by experience: They were 9% more accurate in seeing differences in the spacing of features in upright human faces than in upright monkey faces. Eight-year-olds were 14% less accurate than adults for both human and monkey faces (Experiment 1), and their accuracy for human faces was not higher for children's faces than for adults' faces (Experiment 2). The results indicate that improvements in face recognition after age 8 are not related to experience with human faces and may be related to general improvements in memory or in perception (e.g., hyperacuity and spatial integration). 相似文献
180.
The experiments described in the lead articles by Kowalski and Zimiles and by O'Hanlon and Roberson examine factors that lead to color term acquisition. These experiments touch on the debate regarding the relative contributions of language and concepts in word learning. In this reflection, we examine how conclusions concerning the debate depend deeply on the particular task presented to children, and we propose an alternative approach to studying color term acquisition. 相似文献