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171.
The present study illustrates the usefulness of finite mixture of generalized linear models (GLMs) to examine variability in cognitive strategies during childhood. More precisely, it addresses this variability in set-shifting situations where task-goal updating is endogenously driven. In a task-switching paradigm 5–6-year-olds had to switch between color- and shape-matching rules as a function of a predetermined, predictable task sequence. A finite mixture of GLMs was fitted to explore individual differences in performance. The statistical model revealed five response profiles, defined by accuracy and response times. These response profiles likely correspond to different cognitive strategies with varying efficiency and differential relations to working memory capacity (assessed by backward digit span). These results illustrate the heuristic value of statistical modeling to reveal the behavioral and cognitive variability in the temporal dynamics of children's cognitive functioning.  相似文献   
172.
173.
Research on the psychometric characteristics, including factor structure, of measures assessing emotional intelligence improve our understanding of the manifest and latent dimensions of the construct. The factor structure of the Bar-On Emotional Quotient Inventory (Bar-On, 1997), despite the popularity of the measure, has been the subject of only a few studies, and there are no data available at all on its 30-item version. The aim of our study was the structural analysis of the Bar-On Emotional Quotient Inventory, Youth Version, Short Form (Bar-On & Parker, 2000). During the multiple-step statistical analysis, confirmatory and exploratory factor analyses and a combined method of these were executed on a sample of 2,380 adolescents (mean age: 17 years, 47.9 % male). The results confirmed the original 5-factor structure (Intrapersonal Emotional Quotient, Interpersonal Emotional Quotient, Stress Management, Adaptability, and Positive Impression). However, only 24 of the original 30 items could be considered as belonging to the scales. Elimination of 6 items resulted in a clearer and more coherent factorial structure, which makes the measure an adequate tool for the assessment of the emotional intelligence of adolescents and young adults in surveys of large-scale samples.  相似文献   
174.
Adolescence is characterized by major developmental changes that may render the individual vulnerable to stress and the development of psychopathologies in a sex-specific manner. Earlier we reported lower anxiety-like behavior and higher risk-taking and novelty seeking in rats previously exposed to peri-pubertal stress. Here we studied whether peri-pubertal stress affected the acquisition and extinction of fear memories and/or the associated functional engagement of various brain regions, as assessed with 2-deoxyglucose. We showed that while peri-pubertal stress reduced freezing during the acquisition of fear memories (training) in both sexes, it had a sex-specific effect on extinction of these memories. Moreover hippocampus, basal amygdala and cingulate and motor cortices showed higher metabolic rates during extinction in rats exposed to peri-pubertal stress. Interestingly, activation of the infralimbic cortex was negatively correlated with freezing during extinction only in control males, while only males stressed during puberty showed a significant correlation between behavior during extinction and metabolic activation of hippocampus, amygdala and paraventricular nucleus. No correlations between brain activation and behavior during extinction were observed in females (control or stress). These results indicate that exposure to peri-pubertal stress affects behavior and brain metabolism when the individual is exposed to an additional stressful challenge. Some of these effects are sex-specific.  相似文献   
175.
The purpose of the present study was to analyse the psychometric properties of the 'Questionnaire of Sociocultural Influences on the Aesthetic Body Shape Model' (CIMEC-26) in a Spanish adolescent population. This questionnaire measures the influence of agents and situations that transmit the current aesthetic model, and assesses environmental influences favouring thinness. The CIMEC-26 was administered to a sample of 4031 female primary and secondary school students ranging in age from 10 to 17 years (M?=?14, SD?=?1.34). Results suggested that the CIMEC-26 has acceptable internal consistency (α?=?.93). The oldest group (15-17 years) had the highest scores on all factors and the highest total scores, suggesting greater influence of the aesthetic body shape model and higher vulnerability to social pressure to achieve it. Factor analysis suggested three moderately interrelated components of the scale. Confirmatory factor analysis showed that both the three-factor solution and the original five-factor structure had good fit indices, although the latter showed the best fit. The CIMEC-26 proved to be an effective instrument for research on the social influence on the aesthetic body model in female adolescents.  相似文献   
176.
This study broaches in a novel way the analysis of cognitive impairment characteristic of the early stages of Alzheimer's Disease (AD). Specifically, we attempt to determine the acoustic speech parameters that are sensitive to the onset of the disease, and their association with the language deficit characteristic of AD. Speech analysis was carried out on 21 elderly patients with AD using Praat software, which analyzes the acoustic components of speech. The data obtained were subjected to stepwise regression, using the overall scores obtained in the test as the criterion variable, and the scores on the frequency, amplitude and periodicity variables as predictors of performance. We found that the percentage of voiceless segments explains a significant portion of the variance in the overall scores obtained in the neuropsychological test. This component seems to be related mainly to the patient's ability in phonological fluency. This finding could permit the creation of a diagnostic test for AD through analysis of the acoustic speech parameters at very low cost in terms of both time and resources.  相似文献   
177.
This study used depression (CDI - Kovacs, 1981), anxiety (MASC - March, 1997) and coping strategy (CRI-Y - Moos, 1993) scales and studied the fitness and discriminant validity of reduced versions. The sample consisted of 916 Portuguese pupils, 54.3% feminine, aged 10 to 21 years old. The participants were selected from a set of public schools nation-wide. Two classes were chosen from the 5th to the 12th grades. A set of principal component analyses was carried out in a randomly chosen sample (n = 394) and all the three reduced measures were found to be strongly correlated with the previous. Confirmatory factor analyses (CFA) using the other part of the sample (n = 522) revealed adjustment indexes suggesting a good fit for both the whole model and gender and age groups separately. All scales revealed a good internal consistency. Globally, girls were more anxious and developed more coping strategies than boys. Older students tended to be less depressed, while younger adolescents present higher scores in depression and anxiety and less coping strategies. Reduced scales are sensitive to gender and age differences and can be used in school settings in order to establish a baseline and roadmaps for both universal and selective mental health school based programs.  相似文献   
178.
This study analyzes the prevalence and characteristics of childhood and adolescence sexual abuse suffered by a sample of university students, as well as the variables associated with the nature of abuse. Participants anonymously completed the Questionnaire on Child Sexual Abuse, in order to obtain information about experience of sexual abuse. Of a total of 2,375 students, 289 (12.2%) declared having suffered sexual abuse before the age of 18. The invasiveness, continuity, and severity of abuse was related to the location where the abuse took place (the more severe cases were committed in the homes of the victim and perpetrator) and to the circumstances of abuse (relationships with partners/at a party or while caring for a child predicted more severe abuse). The age of the victim (preschool) and an intrafamilial relationship between victim and perpetrator were also related to more invasive, continuous, and severe sexual abuse. The knowledge of characteristics of perpetrator and victim and the context in which sexual abuse occurs can help to better comprehend the nature and correlates of sexual abuse. The results of the present study may contribute to the design of programs for the prevention of sexual abuse to minors.  相似文献   
179.
The Center for Epidemiologic Studies-Depression Scale (CES-D) is the most frequently used scale for measuring depressive symptomatology in caregiving research. The aim of this study is to test its construct structure and measurement equivalence between caregivers from two Spanish-speaking countries. Face-to-face interviews were carried out with 595 female dementia caregivers from Madrid, Spain, and from Coahuila, Mexico. The structure of the CES-D was analyzed using exploratory and confirmatory factor analysis (EFA and CFA, respectively). Measurement invariance across samples was analyzed comparing a baseline model with a more restrictive model. Significant differences between means were found for 7 items. The results of the EFA clearly supported a four-factor solution. The CFA for the whole sample with the four factors revealed high and statistically significant loading coefficients for all items (except item number 4). When equality constraints were imposed to test for the invariance between countries, the change in chi-square was significant, indicating that complete invariance could not be assumed. Significant between-countries differences were found for three of the four latent factor mean scores. Although the results provide general support for the original four-factor structure, caution should be exercised on reporting comparisons of depression scores between Spanish-speaking countries.  相似文献   
180.
In the last five decades, cognitive scientists and the psychologists of reasoning have dedicated a lot of effort designing usable traffic signs. This study investigated the interference effect produced by the position of the sign elements in traffic signage on response accuracy and reaction time. Sixteen drivers performed a flanker interference reaction time task. Incongruent graphical/space solutions, actually used for the airport stack-type sign, lead to increased reaction time and a reduction in the proportion of correct answers. These results suggest that incongruent visual information should be avoided, as this might impair drivers’ performance. These findings provide important information for the specification of future signage design guidelines and for improving road safety.  相似文献   
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