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91.
Neural correlates of a default response in a delayed go/no-go task   总被引:3,自引:0,他引:3  
Working memory, the ability to temporarily retain task-relevant information across a delay, is frequently investigated using delayed matching-to-sample (DMTS) or delayed Go/No-Go tasks (DGNG). In DMTS tasks, sample cues instruct the animal which type of response has to be executed at the end of a delay. Typically, performance decreases with increasing delay duration, indicating that working memory fades across a delay. However, no such performance decrease has been found when the sample cues exist of present vs. absent stimuli, suggesting that pigeons do not rely on working memory, but seem to respond by default in those trials. We trained 3 pigeons in a DGNG task and found a similar default response pattern: The diverging slopes of the retention functions on correct Go and No-Go trials suggested that pigeons by default omitted their response following No-Go stimuli, but actively retained task-relevant information across the delay for successful responses on Go trials. We conducted single-cell recordings in the avian nidopallium caudolaterale, a structure comparable to the mammalian prefrontal cortex. On Go trials, many neurons displayed sustained elevated activity during the delay preceding the response, replicating previous findings and suggesting that task-relevant information was neurally represented and maintained across the delay. However, the same units did not show enhanced delay activity preceding correct response suppressions in No-Go trials. This activation-inactivation pattern presumably constitutes a neural correlate of the default response strategy observed in the DGNG task.  相似文献   
92.
The purpose of this article is to offer pastoral reflections on the movie by Mel Gibson entitled The Passion of the Christ.  相似文献   
93.
Previous studies reveal the reinforcement of gender stereotypes by picture books children read during the formative years. In these books, boys tend to be portrayed as active leaders, and girls as passive followers. Women and girls are under-represented. Men often exhibit career skills, and women perform traditional tasks in the home. Even when careers are nontraditional, personality characteristics and other qualities and behaviors are often stereotypical. Previous researchers emphasized the narrowly defined roles of women and children in picture books. In this study, we focused on the representation of mothers and fathers, and examined whether men are stereotyped as relatively absent or inept parents. A content analysis of the gender roles exhibited in 200 prominent childrens picture books demonstrated that fathers are largely under-represented, and, when they do appear, they are withdrawn and ineffectual parents. Further research could establish whether seriously deficient models of fatherhood in childrens literature affect the incidence of present, caring fathers in society.  相似文献   
94.
There is currently controversy over the validity and applicability of functional behavioral assessment (FBA) procedures with students with emotional/behavioral disorders (E/BD). A set of FBA procedures, including teacher and student interviews and direct classroom observations, were carried out with eight students with disabilities (7 classified E/BD, one classified LD). Results indicated that when all three methods (teacher/student interviews, classroom observations) yielded a ranking for a function they agreed 64% of those occasions. For those situations in which there was overall disagreement there was agreement between teacher interview and classroom observations most of the time. Social validity data indicated that both students and teachers felt that the assessment procedures were a useful and productive process.  相似文献   
95.
Cognitive deficits associated with early Alzheimers disease (AD) have been recently operationalised in terms of an acquisition deficit and the research supporting this view is presented. However, there is still debate concerning the nature of this deficit and how underlying cognitive processes may be detrimentally affecting the ability to acquire new information in early AD. This review argues that the pattern of cognitive deficits contributing to the acquisition impairment in early AD patients may be readily interpreted within the context of a working memory model. Isolating the component processes of working memory that underlie the acquisition deficit in early AD patients will aid in the design of clinical applications that are focussed at enhancing the ability to acquire new information in everyday life.  相似文献   
96.
This prospective study evaluates emotional functioning and illness representations in 68 unaffected women (34 carriers/34 noncarriers) 1 year after predictive testing for BRCA1/2 mutations when offered within a multidisciplinary approach. Carriers had higher subjective risk perception of breast cancer than noncarriers. Carriers who did not have prophylactic oophorectomy had the highest risk perception of ovarian cancer. No differences were found between carriers and noncarriers regarding perceived seriousness and perceived control of breast and ovarian cancer. Mean levels of distress were within normal ranges. Only few women showed an overall pattern of clinically elevated distress. Cancer-specific distress and state-anxiety significantly decreased in noncarriers from pre- to posttest while general distress remained about the same. There were no significant changes in distress in the group of carriers except for ovarian cancer distress which significantly decreased from pre- to posttest. Our study did not reveal adverse effects of predictive testing when offered in the context of a multidisciplinary approach.  相似文献   
97.
The aim of this study was to examine differences in responses to the Caregiver Strain Questionnaire (CGSQ) between African American and White caregivers of children with emotional and behavioral challenges. Significant item- and scale-level differences were detected across groups with African Americans consistently reporting less strain. We examined whether these differences were more likely due to nonequivalent measurement than to real differences in the experience of caregiver strain. Confirmatory factor analysis showed that the model fit the data well for both racial groups, but there were some differences in structural components. Internal consistency was equivalent across the groups. In an examination of criterion validity, regression analyses showed that African American caregivers experienced a slower rate of increase in objective caregiver strain at a given increase in child internalizing problems. No other race differences were found in the regression analyses. In general, we conclude that the CGSQ can be useful for detecting caregiver strain and identifying family support needs for both White and African American caregivers. Differences across groups in reports of caregiver strain, however, call for more research on racial differences in the impact on the family of caring for a child with emotional and behavioral disorders.  相似文献   
98.
This study investigated developmental differences in some metacognitive variables in ill-defined problem solving and their possible connections with cognitive development in adulthood. Participants were 57 individuals of different ages (adolescents, young adults, mature adults and older adults). They solved one well-defined and six ill-defined problems while their thinking-aloud was taped. They then answered a metacognitive statements questionnaire. Differences in performance were statistically significant in all problems: the best results in interpolation and divergent production problems were achieved by the younger adult group and the best performance on most dialectical everyday problems was found in the mature adults' group. We found no significant differences between age groups in the on-line monitoring of the solving process. Accuracy in metacognitive statements was however significantly better in the mature adult and the younger adult groups. Awareness of and reflection on one's own mental processes showed a similar developmental pattern to relativistic/dialectical thought: low expression in adolescence, an increase in early adulthood, a peak in mature adulthood and a minor decline in later years.  相似文献   
99.
The Role of Temperament in the Etiology of Child Psychopathology   总被引:16,自引:0,他引:16  
A substantial proportion of children and adolescents come to suffer from psychological disorders. This article focuses on the temperament factors that are involved in the pathogenesis of child psychopathology. It is argued that besides the reactive temperament factor of emotionality/neuroticism, the regulative process of effortful control also plays an important role in the etiology and maintenance of internalizing and externalizing problems in youths. More specifically, vulnerability to child psychopathology is determined by a temperament that is characterized by high levels of emotionality/neuroticism and low levels of effortful control. Models are hypothesized in which reactive and regulative temperament factors either have interactive or additive effects on the development of psychological disorders in children, and conceptualized in terms of a developmental psychopathology perspective. Directions for future research and clinical implications of this temperamental view on psychopathology are discussed.  相似文献   
100.
The history of drug/vaccine development has included major advances guided primarily by risk/benefit analyses concerning the innovative agent, not by evidence-based clinical trials (Phase I–IV). Because the approval for new drugs is hindered under the present process, the system requires restructuring. The Phase I/II study period should be more flexible, using the “environment of knowledge” about the new agent, plus risk/benefit assessments. Phase III, as presently constructed, does not add new adverse events data, it provides a narrower profile of drug efficacy than properly done Phase II studies, and placebo-controlled trials continue to raise unresolved ethical and social issues. Phase III studies should be abandoned for most drugs, and substituted with properly powered Phase II doseranging studies plus careful post-marketing surveillance. Phase III should be a penalty for poor drug development, not a regulatory requirement. To accomplish efficient drug development, greater cooperation between pharmaceutical companies and governments in developing clinical trials is needed rather than over-regulation. These changes will synchronize the drug development and regulatory process with the current rapid drug discovery process, reduce drug development time and cost, and improve patient care. The author is Adjunct Professor of Medicine, Weill Medical College of Cornell University, New York, New York, USA.  相似文献   
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