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951.
The neural structures involved in ongoing appetitive and/or observational learning behaviors remain largely unknown. Operant conditioning and observational learning were evoked and recorded in a modified Skinner box provided with an on-line video recording system. Mice improved their acquisition of a simple operant conditioning task by observational learning. Electrical stimulation of the observer's medial prefrontal cortex (mPFC) at a key moment of the demonstration (when the demonstrator presses a lever in order to obtain a reward) cancels out the benefits of observation. In contrast, electrical stimulation of the observer's nucleus accumbens (NAc) enhances observational learning. Ongoing cognitive processes in the demonstrator could also be driven by electrical stimulation of these two structures, preventing the proper execution of the ongoing instrumental task (mPFC) or stopping pellet intake (NAc). Long-term potentiation (LTP) evoked in these two cortical structures did not prevent the acquisition or retrieval process--namely, mPFC and/or NAc stimulation only prevented, or modified, the ongoing behavioral process. The dorsal hippocampus was not involved in either of these two behavioral processes. Thus, both ongoing observational learning and performance of an instrumental task require the active contribution of the mPFC and/or the NAc.  相似文献   
952.
This study analyzes the relationship between lexical and grammatical development in Spanish children. The (European) Spanish version of the MacArthur-Bates CDI was used and administered to 593 Spanish-speaking children between the ages of 16 and 30-months-old. Regression analysis was applied to evaluate the relationship between age, vocabulary (total vocabulary, nouns, and verbs) and grammatical scores on two subsections of the Grammar Part. Total vocabulary explained a significantly greater proportion of variance in grammatical outcomes than age did. However, noun and verb vocabularies did not explain a greater proportion of variance in their respective morphologies than total vocabulary did. Additionally, the predictive relationship between vocabulary and grammar was found to be weaker for children whose scores were below the 10th percentile, although this could be due to the minor variability in this group and to extreme cases. We discuss the implications of these results in relation to the question of continuity between early vocabulary and grammar development in children.  相似文献   
953.
This study had a twofold goal: to define differences in psychological aspects between cancer patients and a control group and to explore the predictive value of such aspects for the evolution of the disease two years later. Firstly, personality, anxiety, anger and depression were assessed in both groups. Results of t-analyses revealed significant group differences. In personality, cancer patients had higher levels of neuroticism and lower levels of extraversion, agreeableness and conscientiousness than the control group. In emotional variables, cancer patients had higher levels of anxiety and some aspects of anger, but there were no group differences in depression levels. Secondly, applying a quasi-prospective design, the predictive value of personality, emotions and coping styles for the evolution of cancer (favourable or unfavourable) was explored using generalized linear models and logistic regression. A four-predictor logistic model was fitted: Anger Expression-In, Resignation, Self-blame and Conscientiousness, indicating that the higher Anger Expression-in, Resignation, and Self-blame scores together with a lower Conscientiousness score, the more likely it is for patients' cancer to evolve unfavourably. These results indicate the crucial role of psychological aspects for the evolution of the disease and the need to include such aspects in the design of clinical interventions.  相似文献   
954.
Expressed emotion (EE) is considered a general predictor of poor outcome across a range of conditions, including eating disorders, and is valuable in measuring the effect of family interventions. There are no self-report questionnaires validated in Spanish to measure EE among relatives of patients with a psychiatric condition. The aim of this study was to examine the psychometric properties of the Spanish version of the Level of Expressed Emotion scale (LEE) among relatives of eating disorder patients. A cross-sectional study of 270 relatives of patients with an eating disorder was conducted to examine the factor structure, reliability and validity of the LEE scale. Results indicated that the LEE-S (Spanish version) did not correspond to the a priori subscales described in the original version. The refined 45-item LEE-S scale consisted of four factors which explained 25.5% of variance in EE for relatives. Reliability was acceptable (alpha ranged from .73 to .86). The discriminant validity of the subscales was moderately supported by correlations with psychological distress (GHQ-12; rho = .34) and specific caregiving experience (EDSIS; rho = .39). The LEE-S instrument has adequate psychometric properties and may be of value to assess families at risk of a negative emotional climate at home.  相似文献   
955.
This paper examines the benefits of regularly playing chess for the intellectual and social-emotional enrichment of a group of 170 schoolchildren from 6-16 years old. It is based on a quasi-experimental design, where the independent variable was the extracurricular activity of chess (n = 170) versus extracurricular activities of soccer or basketball (n = 60). The dependent variable was intellectual and socio-affective competence, which was measured by an IQ test (WISC-R), a self-report test (TAMAI) and a hetero-report questionnaire (teacher-tutor's criterion) applied at the beginning and the end of the academic year. In contrast to the comparison group, it was found that chess improves cognitive abilities, coping and problem-solving capacity, and even socioaffective development of children and adolescents who practice it. The results are modulated, particularly in the area socioaffective, by the personal profile of students who choose practice this activity.  相似文献   
956.
Sexual attraction was considered a component of sexual orientation from the beginning of the second half of the 20th century to present times. However, some recent researchers have studied sexual attraction as an independent field measuring it by the Sexual Attraction Questionnaire (SAQ). This study analyzes sexual attraction through the SAQ in 400 university students from a Peruvian catholic university. These participants -191 women and 209 men- show a very diverse curricular background. The following hypotheses were tested: a) the structure of the SAQ, pointing out two concepts: attraction to men and attraction to women; b) the high inverse correlation between these two concepts or factors; c) the specific impact of this context in sexual attraction: higher percentage of attracted by none of the sexes and lower percentage of attracted to the opposite sex, in comparison with other contexts; and d) the Lippa prediction (2006, 2007), regarding a higher polarization of sexual attraction for men than for women. Results support the first three hypotheses. Clarifications are laid down with regard to the fourth one. Discussion focuses on theoretical and applied advantages of using the SAQ as opposed to the frequent use of a single item of sexual attraction for each sex.  相似文献   
957.
Early partial maternal deprivation causes long-lasting neurochemical, behavioral and brain structural effects. In rats, it causes a deficit in memory consolidation visible in adult life. Some of these deficits can be reversed by donepezil and galantamine, which suggests that they may result from an impairment of brain cholinergic transmission. One such deficit, representative of all others, is an impairment of memory consolidation, clearly observable in a one-trial inhibitory avoidance task. Recent data suggest a role of brain histaminergic systems in the regulation of behavior, particularly inhibitory avoidance learning. Here we investigate whether histamine itself, its analog SKF-91844, or various receptor-selective histamine agonists and antagonists given into the CA1 region of the hippocampus immediately post-training can affect retention of one-trial inhibitory avoidance in rats submitted to early postnatal maternal deprivation. We found that histamine, SKF-91844 and the H2 receptor agonist, dimaprit enhance consolidation on their own and reverse the consolidation deficit induced by maternal deprivation. The enhancing effect of histamine was blocked by the H2 receptor antagonist, ranitidine, but not by the H1 receptor antagonist pyrilamine or by the H3 antagonist thioperamide given into CA1 at doses known to have other behavioral actions, without altering locomotor and exploratory activity or the anxiety state of the animals. The present results suggest that the memory deficit induced by early postnatal maternal deprivation in rats may in part be due to an impairment of histamine mediated mechanisms in the CA1 region of the rat hippocampus.  相似文献   
958.
Physical activity impacts functional recovery following stroke in humans, however its effects in experimental animals submitted to chronic cerebral hypoperfusion have not been investigated. The aim of this study was to evaluate the therapeutic potential of exercise, as assessed by cognitive activity in the Morris water maze and the brain oxidative status, through measurement of macromolecules damage, TBARS levels and total cellular thiols, as well as antioxidant enzymes in hippocampus, striatum and cerebral cortex. Adult male Wistar rats were submitted to the modified permanent bilateral occlusion of the common carotid arteries (2VO) method, with right common carotid artery being first occluded, and tested 3 months after the ischemic event. The effects of three different exercise protocols were examined: pre-ischemia, post-ischemia and pre+post-ischemia. Physical exercise consisted of sessions of 20-min, 3 times per week during 12 weeks (moderate intensity). Rats were submitted to cognitive assessment, in both reference and working spatial memory and after the last testing session were sacrificed to have oxidative stress parameters determined. Hypoperfusion caused a significant cognitive deficit in both spatial water maze tasks and this effect was reversed in rats receiving exercise protocol post and pre+post the ischemic event. Moreover, forced regular treadmill exercise regulated oxidative damage and antioxidant enzyme activity in the hippocampus. These results suggest that physical exercise protects against cognitive and biochemical impairments caused by chronic cerebral hypoperfusion.  相似文献   
959.
IntroductionThe best prevention against relapse results when patients are taught to restructure negative core beliefs (CBs). Efficacy of the trial-based thought record (TBTR) in decreasing the credit given by patients to negative CBs and corresponding emotions was evaluated.MethodPatients (n = 166) were submitted to a simulation of a legal trial to assess their adherence to negative CBs and corresponding emotions after each cognitive therapy technique incorporated by TBTR. RESULTS: Significant reductions existed in percent values after the first and second defense attorney pleas, as well as after jury's verdict and initial preparation for the appeal (p < 0.001), relative to the investigation phase. Significant differences also emerged between the defense attorney's first and second pleas and between the defense attorney's second plea and jury's verdict, as well as preparation for the appeal (p < 0.001). There was no significant difference between percentages presented by patients submitted to TBTR used in the empty chair format relative to the conventional format. Similarly, there was no difference between outcomes, regardless of therapists' level of exposure to TBTR.ConclusionTBTR may help patients reduce attachment to negative CBs and corresponding emotions. Outcomes were significantly favorable regardless of the format use and therapists' level of exposure to TBTR.  相似文献   
960.
Culturally and linguistically appropriate interventions are needed to reduce the risk of driving under the influence (DUI) recidivism among diverse populations. Using core elements of Motivational Interviewing, we developed a culturally relevant web-MI intervention (web-MI) in English and Spanish to serve as a standalone or adjunctive program in DUI educational settings and evaluated its feasibility and acceptability among clients with first-time DUI offenses. We conducted an iterative formative assessment using focus groups with staff (n = 8) and clients (n = 27), and usability interviews with clients (n = 21). Adapting MI for the web was widely accepted by staff and clients. Clients stated the web-MI was engaging, interactive and personal, and felt more comfortable than past classes and programs. Spanish-speaking clients felt less shame, embarrassment, and discomfort with the web-MI compared to other in-person groups. Results support the viability of web-MI for DUI clients at risk for recidivism and highlight the importance of adapting the intervention for diverse populations. Key decisions used to develop the web-MI are discussed.  相似文献   
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