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101.
Background/Objective: This study aims to characterize the differences on the short-term temporal network dynamics of the undirected and weighted whole-brain functional connectivity between healthy aging individuals and people with mild cognitive impairment (MCI). The Network Change Point Detection algorithm was applied to identify the significant change points in the resting-state fMRI register, and we analyzed the fluctuations in the topological properties of the sub-networks between significant change points. Method: Ten MCI patients matched by gender and age in 1:1 ratio to healthy controls screened during patient recruitment. A neuropsychological evaluation was done to both groups as well as functional magnetic images were obtained with a Philips 3.0T. All the images were preprocessed and statistically analyzed through dynamic point estimation tools. Results: No statistically significant differences were found between groups in the number of significant change points in the functional connectivity networks. However, an interaction effect of age and state was detected on the intra-participant variability of the network strength. Conclusions: The progression of states was associated to higher variability in the patient's group. Additionally, higher performance in the prospective and retrospective memory scale was associated with higher median network strength.  相似文献   
102.
An evaluation of food type and texture indicated that both variables affected the expulsions of a 3-year-old with feeding problems. The results of the evaluation were used to prescribe a treatment (reducing the texture of one food type) that reduced expulsion.  相似文献   
103.
The experiments described in the lead articles replicate findings from previous studies of development of knowledge about balance scales, add several new findings, and raise four key questions: (a) How can rule use best be assessed? (b) How can we reconcile systematic use of rules with variable use of strategies? (c) When do children begin to use rules? and (d) How do children generate new rules? In this Reflection, we summarize current understanding of development of knowledge about balance scales and consider each of the four questions.  相似文献   
104.
Two predictions derived from Markovits and Barrouillet's (2001) developmental model of conditional reasoning were tested in a study in which 72 twelve-year-olds, 80 fifteen-year-olds, and 104 adults received a paper-and-pencil test of conditional reasoning with causal premises ("if cause P then effect Q"). First, we predicted that conditional premises would induce more correct uncertainty responses to the Affirmation of the consequent and Denial of the antecedent forms when the antecedent term is weakly associated to the consequent than when the two are strongly associated and that this effect would decrease with age. Second, uncertainty responding to the Denial of the antecedent form ("P is not true") should be easier when the formulation of the minor premise invites retrieval of alternate antecedents ("if something other than P is true"). The results were consistent with the hypotheses and indicate the importance of retrieval processes in understanding developmental patterns in conditional reasoning with familiar premises.  相似文献   
105.
Thirty preschoolers rated as hard to manage on Goodman's (R. Goodman, 1997) Strengths and Difficulties Questionnaire (SDQ), and a group of matched control children were observed and recorded on audiotape at home, interacting with their mothers (Time 1). At the 18-month follow-up home visits (Time 2), the children and mothers were filmed across 4 observation settings. Mother–child interactions were rated on affect, control, responsiveness and connectedness of communication. At Time 1, mothers of the hard to manage group used more negative control and engaged in fewer connected conversations than did mothers in the control group. At Time 2, mothers of the hard to manage group displayed higher levels of negative control and lower levels of positive control. These results are discussed in terms of the importance of examining connected communication and different observation contexts when examining dyadic mother–child interactions.  相似文献   
106.
This study reports on the predictive value and clinical usefulness of the Dutch parental version of the Dental Subscale of the Children's Fear Survey Schedule (CFSS-DS). Parents of 718 children (4–12 years) completed this CFSS-DS version before or during the child's visit. The dentist rated the child's dental fear during treatment on a 5-point Likert-type Scale from 1 (not afraid at all) to 5 (very afraid). Reliability analysis was performed, and correlation coefficients between the two measures were calculated. The reliability of the scale proved to be high (Cronbach's = .93) and significant correlation coefficients were found (r = .58 and r = .68, p < .01). The negative predictive value of the CFSS-DS was high (.96), whereas its positive predictive value was relatively low (0.41). It was concluded that the CFSS-DS might be of clinical value as a screening device of dental fear, whereas its predictive value of fearful behavior should not be overestimated.  相似文献   
107.
The prevalence, structure, stability, and predictors of change in early behavior problems were examined in a population-based sample of Norwegian children at 18 and 30 months of age (N = 750). A clear factor structure involving four dimensions emerged at both assessment times: Two factors were characterized by externalizing behaviors and were labeled Social Adjustment and Overactive-Inattentive; one factor tapped internalizing problems and was labeled Emotional Adjustment; and the fourth, related to general immaturity, was labeled Regulation. Specific patterns of child and family risk factors were associated with stability and change over the two time points for each factor. Children with stable problems had the most problematic characteristics on all significant predictors, followed by children with problems at one, but not both, time points. The data suggest that it is possible to identify risk factors for stable problems at 18 months, allowing some prediction of those children whose problems will persist over early childhood. Since specific risk factors emerged for specific types of behavior problems, the results may provide some much-needed guidance to early intervention efforts.  相似文献   
108.
中小学生认知能力发展水平测验的研究   总被引:4,自引:0,他引:4  
以皮亚杰的认知发展理论为基础,采用皮亚杰及其学生研究认知发展时的任务为测验题目,编制成测量中小学生认知能力发展水平的测验.通过对2240名中小学生施测,结果表明本测验不仅具有很好的信度和效度,而且也具有适中的难度.然后以一所中学特长班学生为被试,通过对他们进行测量,并将测验结果与同年级普通班学生的认知成绩进行比较,结果存在很明显的差异.最后对中小学生认知能力发展水平测量问题进行了探讨.  相似文献   
109.
Needham A  Dueker G  Lockhead G 《Cognition》2005,94(3):215-240
Four- and-a-half-month-old infants' (N = 100) category formation and use was studied in a series of five experiments. For each experiment, the test events featured a display composed of a cylinder and a box. Previous research showed that this display is not clearly parsed as a single unit or as two separate units by infants of this age. Immediately prior to testing, infants were shown a set of category exemplars. Knowledge about this category could help infants disambiguate the test display, which contained a novel exemplar of this category. Clear interpretation of the test display as composed of two separate units (as indicated by infants' longer looking at the move-together than at the move-apart test event) was taken as evidence of category formation and use. In Experiments 1 and 5, infants' prior experience with a set of three different boxes that were similar to the test box facilitated their segregation of the test display. Experiment 2 showed that three different exemplars are necessary: prior experience with any two of the three boxes used in Experiment 1 did not facilitate infants' segregation of the test display. Experiment 3 showed that variability in the exemplar set is necessary: prior experience with three identical boxes did not facilitate infants' segregation of the test display. Experiment 4 showed that under these conditions of very brief prior exposure, similarity between the exemplar set and test box is necessary: prior experience with three different boxes that were not very similar to the test box did not facilitate infants' segregation of the test display. Together, these findings suggest that: (a) number of exemplars, variability, and similarity in the exemplar set are important for infants' category formation, and (b) infants use their category knowledge to determine the boundaries of the objects in a display.  相似文献   
110.
There is a wealth of data indicating the effectiveness of cognitive behavioral therapy in the treatment of bulimia nervosa. However, the best evidence indicates a treatment success rate of 50%. The purpose of this paper is to briefly describe cognitive behavioral treatment of bulimia nervosa and to offer suggestions on how this therapy approach may be tailored to best serve the needs of individual clients. Such tailoring should ultimately lead to even greater treatment success.  相似文献   
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