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81.
What response times tell of children's behavior on the balance scale task   总被引:4,自引:0,他引:4  
Analysis of accuracy of responses to balance scale problems gives a global idea of the cognitive processes that underlie problem-solving behavior on this task. We show that response times (RTs) provide additional detailed information about the kind and duration of these processes. We derive predictions about the RTs from Siegler's (1981) model for the balance scale task, including the counterintuitive prediction that young adults are slower than children in solving particular balance scale problems. The predictions were tested in a study in which 191 6- to 22-year-old participants were presented with a computerized balance scale task. RTs were analyzed with regression models. In addition to qualitative differences between items, we also modeled quantitative differences between items in the regression models. Analyses supported the predictions and provided additional knowledge on the rules. Rule II was reformulated as a rule that always involves the encoding, but not always the correct application of the distance cue. RTs provided evidence for the use of a buggy-rule and not an addition-rule. Finally, a relation between rule inconsistency and increased RT was found.  相似文献   
82.
The present paper focuses on two studies, one on English (Schneiderman & Saddy, 1988) and the other on Italian (De Vreese, Neri Rubichi, & Salvioli, 1996), which report on right hemisphere damaged subjects' inability to correctly insert a word or phrase into an already well-formed sentence under certain stimulus conditions. Despite their strikingly similar findings, the results of the studies are interpreted quite differently. Schneiderman & Saddy consider the deficit to be syntactic, while De Vreese et al. view it as occurring at the lexical category or morphological level. An analysis and regrouping of the stimulus items from both studies indicate that a single syntactic interpretation could account for their results. Suggestions are made for further analyses and research to increase our understanding of the syntactic capacities of the intact right hemisphere.  相似文献   
83.
The long-term effect of transplanting embryonic frontal cortex into a unilateral frontal cortex lesion has been studied in adult rats. Before surgery, activity in an open field, muscular strength of both forelimbs, and performance in a paw-reaching-for-food task were scored in 26 rats. In 21 animals a unilateral cortex lesion was then made in the forelimb motor area of the hemisphere contralateral to the preferred paw in the paw-reaching-for-food task, while the other 5 animals were sham-operated. On retesting, the lesion animals changed the preferred paw. A solid homotopic transplant of embryonic tissue (embryonic day 17) was then placed in the lesion cavity in 11 of the lesion rats. Three months later neither lesion alone nor lesion plus transplantation affected open field behavior and muscular strength, but the lesion permanently affected performance in the paw-reaching-for-food task, as shown by a change of preferred paw and a functional deficit in the paw contralateral to the lesion. Transplantation ameliorated the deficits caused by the lesion, but this was only evident when animals were forced to reach with the paw contralateral to the lesion plus transplant. The behavioral results were independent of the size of the lesion and graft. Connections between graft and host tissue were studied by means of the fluorescent tracer 1,1'-dioctadecyl-3,3,3'3'-tetramethylindocarbocyanine perchlorate (DiI). A dense array of labeled fibers was found in the host cortex adjacent to the transplant. The results suggest that functional recovery depends on grafting but is only evident when the animal is obliged to use the affected limb.  相似文献   
84.
In search of the minimal requirements for transitive reasoning, a simple neural network was trained and tested on the non-verbal version of the conventional "five-term-series task" – a paradigm used with human adults, children and a variety of non-human species. The transitive performance of the network was analogous in several aspects to that reported for children and animals. The three effects usually associated with transitive choices i.e. "symbolic distance", "lexical marking" and "end-anchor", were also clearly shown by the neural network. In a second experiment, where the training conditions were manipulated, the network failed to match the behavioural pattern reported for human adults in the test following an ordered presentation of the premises. However, it mimicked young children's performance when tested with a novel comparison term. Although we do not intend to suggest a new model of transitive inference, we conclude, in line with other authors, that a simple error-correcting rule can generate transitive behaviour similar to the choice pattern of children and animals in the binary form of the five-term-series task without requiring high-order logical or paralogical abilities. The analysis of the training history and of the final internal structure of the network reveals the associative strategy employed. However, our results indicate that the scope of the associative strategy used by the network might be limited. The extent to which the conventional five-term-series task, in absence of appropriate manipulations of training and testing conditions, is suitable to detect cognitive differences across species is also discussed on the basis of our results. Accepted after revision: 29 May 2001 Electronic Publication  相似文献   
85.
大学毕业生的职业期望及其影响因素研究   总被引:28,自引:2,他引:26  
本研究对当代大学生职业期望所包括的关键因素以及各因素之间的结构模式进行了深入分析,从职业动机、自我意识、环境意识以及个人的职业发展计划等多种不同角度对影响职业期望的因素进行了有益的探索,并在此基础上建立了"当代大学生职业期望的初步模型".  相似文献   
86.
This article focuses on the development of adolescent resilience and protective factors within a sample of 86 inner-city high school students in Chicago. Resilience was considered present when (a) children living in conditions of risk (b) show better-than-predicted outcomes (c) presumably due to some intervening process. Conditions (a) and (b) were met using quantitative comparisons. Condition (c), the intervening process, was examined using autobiographical essays to begin to understand protective factors youth consider salient in overcoming adversity. Internal attributes such as perseverance, determination, and having the awareness to learn from the risk-attrition process surfaced in the content analyses. Motivational support from family members and teachers was also highly valued for promoting successful adjustment.  相似文献   
87.
Although response inhibition has been proposed as a core element of child attention-deficit hyperactivity disorder (ADHD), the literature is heavily reliant on studies using DSM–III–R diagnostic criteria, older methods of measuring response inhibition, samples of boys, and failing to control thoroughly for comorbid problems—both as diagnoses and as subclinical variation. The present study replicated a deficit in response inhibition in the ADHD combined type (DSM–IV, American Psychiatric Association, 1994) using samples matched on age and sex. The study replicated an effect size of approximately d = .6 in boys with ADHD, and observed an even larger effect size for girls, although the Sex × Group interaction was nonsignificant. Children with ADHD also had problems with response output, shown by variable responding. Excluding comorbid conduct disorder, reading disorder, generalized anxiety disorder, obsessive–compulsive disorder, major depression, and posttraumatic stress disorder from the sample did not alter the results. Correlations indicated that response inhibition was associated with both attentional problems and reading level. Covarying for reading problems did not eliminate the ADHD group effect, but the association of response inhibition with reading clearly requires further examination. Overall, the study supported the role of response inhibition in the DSM–IV ADHD combined type, but with key qualifications as to degree of specificity in reference both to comorbid problems and other executive functions.  相似文献   
88.
伪医学国际化之成因   总被引:1,自引:0,他引:1  
伪医学的表现形式多种多样,且存在于世界的各个角落,功利思想的驱动、职业道德的沦丧,使传播者见利忘义;医学水平的局限、本能的求生意识诱发了人们求助伪医学的侥幸心理;医巫同源的影响、伪医学的心理调控作用模糊了人们对其本质的认识;贫困者对现代医疗费用的畏惧、富有者对健康长寿的奢望为伪医学提供了广阔的市场;文化差异的存在,使伪医学拥有了生长的土壤  相似文献   
89.
Conduct Disorder in Girls: A Review of the Literature   总被引:8,自引:0,他引:8  
The study of Conduct Disorder (CD) has primarily been limited to boys. The lack of research resulted from a premise that CD in girls was rare. However, CD in girls is a relatively common psychiatric diagnosis, and appears to be associated with several serious outcomes, such as Antisocial Personality Disorder and early pregnancy. Understanding gender differences in the course and severity of CD may lead to important information about etiology. Empirical studies on precursors, developmental course, risk factors and treatment for CD in girls are reviewed, while highlighting similarities and differences between girls and boys. Generally, CD symptoms in girls are stable. Precursors to CD in girls probably include Oppositional Defiant Disorder and temperamental factors, but also may include certain negative cognitions. What distinguishes CD in girls is the high risk they have to develop comorbid conditions, especially internalizing disorders. Risk factors for CD in girls partly overlap with those known for boys, but some factors appear to be highly salient for girls. Finally, there may be some significant effects of gender on treatment efficacy. Implications of these findings for future etiologic research are discussed.  相似文献   
90.
Alzheimer's disease remains the most common form of dementia. Dementia symptoms vary depending on individual personality, life experience, and social and cultural influences. As dementia progresses, involvement of multi-disciplinary health care professionals is needed to manage the disease. Alzheimer research is progressing rapidly. While 5% of all Alzheimer's disease may be genetically determined, the majority is not. Susceptibility genes can reveal the risk of contracting Alzheimer's disease. Early life risk factors such as education, nutrition, and vascular disease may increase the likelihood of dementia in later life. In the United States, two acetylcholinesterase inhibitors have been approved as cognitive enhancers. Possible prevention and symptomatic treatment interventions have focused on estrogen replacement therapy, antioxidants, and anti-inflammatory medications. Research advances have improved the clinical management of dementia. Ethical implications to the patient, family, and society are multiple and remain challenging.  相似文献   
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