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941.
This study tested whether childhood parental emotional abuse and peer emotional bullying serve as antecedents of depression in adolescence and identified the cognitive mechanisms involved in this process. It was hypothesized that the experience of emotional abuse would predict depressive symptoms via development of rumination and negative inferences. A 3-wave longitudinal study was carried out with 998 adolescents (471 girls and 526 boys) between 13 and 17 years of age. Results showed that emotional abuse by parents and peers at Time 1 predicted a worsening of several cognitive vulnerabilities at Time 2. In addition, brooding mediated between the experiences of abuse and the increase of depressive symptoms at Time 3. Thus, findings suggest that the experiences of childhood emotional abuse by parents and peers serve as antecedents to develop a negative cognitive style, vulnerability that, once developed, is a risk factor for the onset of depressive symptoms in adolescence.  相似文献   
942.
Top predators inhabiting a dynamic environment, such as coastal waters, should theoretically possess sufficient cognitive ability to allow successful foraging despite unpredictable sensory stimuli. The cognition-related hunting abilities of marine mammals have been widely demonstrated. Having been historically underestimated, teleost cognitive abilities have also now been significantly demonstrated. Conversely, the abilities of elasmobranchs have received little attention, despite many species possessing relatively large brains comparable to some mammals. The need to determine what, if any, cognitive ability these globally distributed, apex predators are endowed with has been highlighted recently by questions arising from environmental assessments, specifically whether they are able to learn to distinguish between anthropogenic electric fields and prey bioelectric fields. We therefore used electroreceptive foraging behaviour in a model species, Scyliorhinus canicula (small-spotted catshark), to determine cognitive ability by analysing whether elasmobranchs are able to learn to improve foraging efficiency and remember learned behavioural adaptations. Positive reinforcement, operant conditioning was used to study catshark foraging behaviour towards artificial, prey-type electric fields (Efields). Catsharks rewarded with food for responding to Efields throughout experimental weeks were compared with catsharks that were not rewarded for responding in order to assess behavioural adaptation via learning ability. Experiments were repeated after a 3-week interval with previously rewarded catsharks this time receiving no reward and vice versa to assess memory ability. Positive reinforcement markedly and rapidly altered catshark foraging behaviour. Rewarded catsharks exhibited significantly more interest in the electrical stimulus than unrewarded catsharks. Furthermore, they improved their foraging efficiency over time by learning to locate and bite the electrodes to gain food more quickly. In contrast, unrewarded catsharks showed some habituation, whereby their responses to the electrodes abated and eventually entirely ceased, though they generally showed no changes in most foraging parameters. Behavioural adaptations were not retained after the interval suggesting learned behaviour was not memorised beyond the interval. Sequences of individual catshark search paths clearly illustrated learning and habituation behavioural adaptation. This study demonstrated learning and habituation occurring after few foraging events and a memory window of between 12 h and 3 weeks. These cognitive abilities are discussed in relation to diet, habitat, ecology and anthropogenic Efield sources.  相似文献   
943.
Proactive interference (PI) occurs when previously learned information interferes with new learning. In a working memory task, PI induces longer response times and more errors to recent negative probes than to new probes, presumably because the recent probe’s familiarity invites a “yes” response. Warnings, longer intertrial intervals, and the increased contextual salience of the probes can reduce but not eliminate PI, suggesting that cognitive control over PI is limited. Here we tested whether control exerted in the form of intentional forgetting performed during working memory can reduce the magnitude of PI. In two experiments, participants performed a working memory task with directed-forgetting instructions and the occasional presentation of recent probes. Surprise long-term memory testing indicated better memory for to-be-remembered than for to-be-forgotten items, documenting the classic directed-forgetting effect. Critically, in working memory, PI was virtually eliminated for recent probes from prior to-be-forgotten lists, as compared to recent probes from prior to-be-remembered lists. Thus cognitive control, when executed via directed forgetting, can reduce the adverse and otherwise persistent interference from familiarity, an effect that we attribute to attenuated memory representations of the to-be-forgotten items.  相似文献   
944.
“The Scaffolding Theory of Aging and Cognition (STAC)”, proposed in 2009, is a conceptual model of cognitive aging that integrated evidence from structural and functional neuroimaging to explain how the combined effects of adverse and compensatory neural processes produce varying levels of cognitive function. The model made clear and testable predictions about how different brain variables, both structural and functional, were related to cognitive function, focusing on the core construct of compensatory scaffolding. The present paper provides a revised model that integrates new evidence about the aging brain that has emerged since STAC was published 5 years ago. Unlike the original STAC model, STAC-r incorporates life-course factors that serve to enhance or deplete neural resources, thereby influencing the developmental course of brain structure and function, as well as cognition, over time. Life-course factors also influence compensatory processes that are engaged to meet cognitive challenge, and to ameliorate the adverse effects of structural and functional decline. The revised model is discussed in relation to recent lifespan and longitudinal data as well as emerging evidence about the effects of training interventions. STAC-r goes beyond the previous model by combining a life-span approach with a life-course approach to understand and predict cognitive status and rate of cognitive change over time.  相似文献   
945.
Anecdotal accounts suggest some patients have experienced negative outcomes as a result of receiving genetics services from non-genetics providers, but empirical evidence of these incidents and their outcomes is limited. This study examined genetic counselors’ perceptions of the occurrence of such incidents in the state of Minnesota. Twenty-five genetic counselors completed an on-line survey and 20 also participated in a semi-structured telephone interview. The interviewees recalled and described 37 specific incidents they perceived as having negative outcomes for patients and/or their families. Inductive and cross-case analysis revealed common themes including: adverse psychosocial effects, inadequate genetic counseling, genetic testing and screening errors, medical mismanagement, negative shifts in attitudes toward medical providers, and unnecessary use of health care resources. Commonly mentioned strategies for preventing/mitigating negative outcomes included: educational outreach and awareness programs for medical providers and the general public, standardized testing and screening processes, and implementing mechanisms for reporting and addressing adverse events. Additional findings, practice and policy implications, and research recommendations are discussed.  相似文献   
946.
Preimplantation genetic diagnosis (PGD) is an innovative prenatal testing option because the determination of whether a genetic disorder or chromosomal abnormality is evident occurs prior to pregnancy. However, PGD is not covered financially under the majority of private and public health insurance institutions in the United States, leaving couples to decide whether PGD is financially feasible. The aim of this qualitative study was to understand the role of finances in the decision-making process among couples who were actively considering PGD. In-depth, semi-structured interviews were completed with 18 genetic high-risk couples (36 individual partners). Grounded theory guided the analysis, whereby three themes emerged: 1) Cost is salient, 2) Emotions surrounding affordability, and 3) Financial burden and sacrifice. Ultimately, couples determined that the opportunity to avoid passing on a genetic disorder to a future child was paramount to the cost of PGD, but expressed financial concerns and recognized financial access as a major barrier to PGD utilization.  相似文献   
947.
The purpose of this study was to examine rates of child abuse and neglect reports following a community implementation of Parent–Child Interaction Therapy (PCIT), an evidence-supported intervention for the prevention of maltreatment. Among a group of families receiving PCIT, predictors of reports were examined including family demographics, course of treatment, changes in clinical measures, and caregiver report for prior maltreatment victimization and perpetration. Participants (n = 120) included families at-risk for future maltreatment with and without prior maltreatment history. Agency case records were linked with state administrative records of child welfare reports. Time to follow-up ranged from 13 to 40 months. Bivariate and multivariate survival analyses were used to model risk for a later report. During the follow-up period, 12.5 % of families had a report for physical abuse or neglect. Reports of prior victimization as a child and prior perpetration as an adult were strong predictors of a report of perpetration after PCIT. Dosage of PCIT and change in clinical measures did not increase risk for a later report. PCIT can be an effective intervention for preventing maltreatment. Family history of child welfare involvement is a prominent factor in assessing risk for future involvement.  相似文献   
948.
Prior research evaluating health-related quality of life (HRQOL) among pediatric patients with internal cardiac devices has primarily focused on children with cardiac defibrillators, with scant attention devoted to pacemaker recipients. Social support has been conceptualized as a protective factor that partially accounts for differences in HRQOL. This study compares the HRQOL of children with pacemakers with that of healthy children, and examines associations between HRQOL and social support. Twenty-seven pediatric pacemaker recipients completed measures of HRQOL and social support. Their parents also completed measures of child HRQOL. High concordance was found for child and parent-proxy reports of child HRQOL. Children with pacemakers and their parents both reported relatively low child HRQOL when compared to published normative data for healthy children and parents of healthy children. Family and friends emerged as the sources of support positively associated with the greatest number of HRQOL domains. In conclusion, these findings suggest that pediatric pacemaker recipients experience lower levels of HRQOL compared to healthy peers, and that social support from those closest to the child is associated with their perceived HRQOL.  相似文献   
949.
The present study investigated the relation between reaction to negative stimuli and memory for stimuli. The relation was further investigated using as a framework individuals’ affective temperaments (AFTs). Eighty adolescents participated in the study. The AFTs are based on selfreported affect and categorizes individuals in four temperaments: self-actualizing, high affective, low affective and self-destructive. Reaction to negative stimuli was measured by interpretation of specific words in a short story. Two days later, participants were presented with a list of words and asked which of them were present in the short story. Individuals’ AFTs were expected to predict the promotion of pleasure or the prevention of displeasure. On a general level, reaction to negative stimuli predicted memory for negative, positive and neutral words. At an individual level, self-actualizers and high affectives’ negative reaction predicted the memory of positive words (i.e., promotion). In contrast, low affectives’ negative and positive reaction predicted the memory of neutral words (i.e., prevention).  相似文献   
950.
Laboratory animals should be provided with enrichment objects in their cages; however, it is first necessary to test whether the proposed enrichment objects provide benefits that increase the animals’ welfare. The two main paradigms currently used to assess proposed enrichment objects are the choice test, which is limited to determining relative frequency of choice, and consumer demand studies, which can indicate the strength of a preference but are complex to design. Here, we propose a third methodology: a runway paradigm, which can be used to assess the strength of an animal’s motivation for enrichment objects, is simpler to use than consumer demand studies, and is faster to complete than typical choice tests. Time spent with objects in a standard choice test was used to rank several enrichment objects in order to compare with the ranking found in our runway paradigm. The rats ran significantly more times, ran faster, and interacted longer with objects with which they had previously spent the most time. It was concluded that this simple methodology is suitable for measuring rats’ motivation to reach enrichment objects. This can be used to assess the preference for different types of enrichment objects or to measure reward system processes.  相似文献   
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