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941.
942.
In this study, we analyzed the participation of the entorhinal cortex in extinction of a learned aversive response. Rats with infusion cannulae aimed to the entorhinal cortex were trained in a one-trial step-down inhibitory avoidance task (IA) and submitted to four consecutive daily test sessions without the footshock, a procedure that induced extinction of the conditioned response in control animals. When infused into the entorhinal cortex immediately after the first extinction session at doses able to block consolidation of IA memory, the NMDA receptor antagonist, AP5 (25 nmol/side), the inhibitor of protein synthesis anisomycin (300 nmol/side) and the inhibitor of CaMKII, KN-93 (10 nmol/side), but not the MEK1/2 inhibitor PD-98059 (5 nmol/side) hindered extinction of the IA response. The same results were obtained when the interval between the first and second test session was 48 instead of 24h. The data indicate that normal functionality of the NMDA receptors, together with CaMKII activity and protein synthesis are necessary in the entorhinal cortex at the time of the first test session to generate extinction. Our results also suggest that the ERK1/2 pathway does not play a role in this process.  相似文献   
943.
Research on deductive reasoning in adolescents and adults has shown that errors in deductive logic are not necessarily due to a lack of logical ability but can stem from an executive failure to inhibit biases. Few studies have examined this dissociation in children. Here, we used a negative priming paradigm with 64 children (8-10 years old) to test the role of cognitive inhibition in syllogisms with belief-bias effects. On trials where negative priming was predicted, results were as follows: For the first syllogism (A), the strategy 'unbelievable-equals-invalid' had to be inhibited. The logic of the syllogism led to affirming a conclusion inconsistent with one's knowledge of the world, such as 'All elephants are light.' For the second syllogism (B), one's real-world knowledge and the syllogism's logic were congruent but the latter required affirming exactly what had been inhibited for A (i.e. that elephants are heavy). A negative priming effect on the A-B sequence was reflected in a significant drop in reasoning performance on B. This supports the idea that during cognitive development, inhibitory control is required for success on syllogisms where beliefs and logic interfere.  相似文献   
944.
This article introduces the software program called EthoSeq, which is designed to extract probabilistic behavioral sequences (tree-generated sequences, or TGSs) from observational data and to prepare a TGS-species matrix for phylogenetic analysis. The program uses Graph Theory algorithms to automatically detect behavioral patterns within the observational sessions. It includes filtering tools to adjust the search procedure to user-specified statistical needs. Preliminary analyses of data sets, such as grooming sequences in birds and foraging tactics in spiders, uncover a large number of TGSs which together yield single phylogenetic trees. An example of the use of the program is our analysis of felid grooming sequences, in which we have obtained 1,386 felid grooming TGSs for seven species, resulting in a single phylogeny. These results show that behavior is definitely useful in phylogenetic analysis. EthoSeq simplifies and automates such analyses, uncovers much of the hidden patterns of long behavioral sequences, and prepares this data for further analysis with standard phylogenetic programs. We hope it will encourage many empirical studies on the evolution of behavior.  相似文献   
945.
A stress management programme for Crohn's disease   总被引:3,自引:0,他引:3  
The present study was designed to assess the effectiveness of techniques of behavioural assessment and treatment of Crohn's disease (CD). On the assumption that stress events have a pronounced influence on the life of Crohn's patients, we proposed stress management treatment. This is intended to control stress and improve patients' personal and social competence. Forty-five patients with Crohn's disease were randomly assigned to one of three treatment groups, two experimental groups: stress management and self-directed stress management, and a control group: conventional medical treatment. The subjects underwent eight individual sessions which were specific to each condition. All subjects completed symptom monitoring diaries. The subjects who received training in stress management experienced a significant post-treatment reduction of tiredness (P < 0.1), constipation (P < 0.1), abdominal pain (P < 0.5) and distended abdomen (P < 0.5). The subjects who received training in self-directed stress management experienced a significant reduction in tiredness (P < 0.1) and abdominal pain (P < 0.5). No significant changes were observed in symptomatology in the conventional medical treatment group. Similar results were obtained in the 12 month follow-up.  相似文献   
946.
The present study compared two methods for assessing binge eating and related eating disorder psychopathology in obese children and adolescents. A comparison was made between the child version of the Eating Disorder Examination (ChEDE) and the self-report version of the interview (ChEDE-Q). A total of 139 children and adolescents (aged 10-16 years) seeking inpatient treatment for obesity completed the ChEDE questionnaire and were administered the ChEDE interview afterwards. The ChEDE and ChEDE-Q were significantly correlated for the four subscales: restraint, eating concern, weight concern and shape concern. The ChEDE-Q generated consistently higher levels of eating disorder psychopathology. There was a significant discrepancy for the assessment of a more complex feature such as binge eating. Overall, the current study found lower levels of agreement between the EDE and EDE-Q than previously reported in adult samples. It appears that children and adolescents have difficulties in identifying binge-eating episodes when they receive no detailed instruction. It is concluded that a clinical interview is necessary to identify eating disorders in obese children and that a self-report questionnaire can only be used as a screening tool. Even then, thorough clarification of the definition of the eating disorder features is needed when using a self-report questionnaire.  相似文献   
947.
The authors investigated distracter effects on the kinematics of reaching movements to determine when during reaching responses (reaction time, time to peak velocity, time after peak velocity, or peak velocity) distracter interference occurred and how target-distracter separation affected the locus of interference. Participants moved a pen on a digitizing tablet toward a target appearing with or without a distracter. With a small target-distracter separation, distracter interference occurred during time after peak velocity (similar amounts of interference from near and far distracters). With a large target-distracter separation, distracter interference occurred during time to peak velocity (more interference from near compared to far distracters). The results demonstrated that target-distracter separation is an important determinant of the locus of distracter interference.  相似文献   
948.
Trait structures resulting from personality assessments on Likert scales are affected by the additive and multiplicative transformations implied in interval scaling and correlational analysis. The effect comes into view on selecting a plausible alternative scale. To this end, we propose a bipolar bounded scale ranging from -1 to +1 representing an underlying process in which the assessor would review and discount positive and negative behavioral instances of a trait. As an appropriate index of likeness between variables X and Y, we propose LXY = SigmaXY/N, the average of the raw scores cross products. Using this index, we carried out a raw scores principal component analysis on data consisting of 133 participants who had each been rated by 5 assessors including self on 914 items. Contrary to the Big-Five structure that was found in these data on standard analysis, the results showed a relatively large first principal component F1 and 2 very small ones, F2 and F3. The sizes LFF=SigmaF2/N, the averages of the squared component scores, were modest to small. It thus appears that the scale, bipolar proportional versus standard, has a profound impact on the size and structure of personality assessments. The dissimilarity remains on analyzing self-ratings rather than averaged (over the 5 assessors) ratings.  相似文献   
949.
Harter's Self-perception Profile for Children was designed to assess children's domain-specific judgments of their competence (scholastic, social, athletic, physical, and behavioral), as well as global self-worth. The psychometric properties and exploratory factor analysis of the profile for two Spanish samples of children (49% boys and 51% girls; M age=11.1 yr., SD=9.7), were examined (n=23 from an after-school social care center in an economically deprived neighborhood and n=120 from a private school mainly enrolling families of medium socioeconomic status). All attending children between 9 and 12 yr. old were included. Analysis showed sex differences, with girls scoring lower than boys on Athletic Competence and higher on Behavioral Conduct. Children from the economically deprived group had higher scores on Social Acceptance and lower scores on Physical Appearance. The cross-cultural analysis showed that the Spanish control group scored significantly higher than the original American control group on Global Self-worth. A Spanish validation with 9- to 12-yr.-olds clearly replicated the five-factor structure reported by Harter in 1985 and also replicated the results obtained in other European samples, showing reliable and valid psychometric properties.  相似文献   
950.
The present study investigated the following issues: (1) the structure of Bryant's Empathy Index for children and adolescents in a Spanish sample of 408 boys and 424 girls (M age=14.4 yr.), and (2) sex differences, including effect sizes and internal consistency of the scale. A principal components factor analysis with oblimin rotation showed that 20 of the index's 22 items load on three robust factors, related to Feelings of Sadness, Understanding Feelings, and Tearful Reaction with regard to the emotions of others. The 3-factor structure obtained an adequate fit to the data in the confirmatory factor analysis. Coefficients alpha ranged between .72 and .78. The 3 factors accounted for 42% of variance. As expected, girls scored higher than boys. It was concluded that the Spanish version of Bryant's Empathy Index has an acceptable reliability and construct validity, making it useful for research.  相似文献   
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