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151.
Endocannabinoids (eCBs) modulate a variety of brain functions via activation of the widely expressed CB1 receptor. One site of high density of this receptor is the basolateral amygdala (BLA), a structure involved in the formation of aversive memories. The activation and blockade of CB1 receptors by systemic or hippocampal drug administrations have been shown to modify memory processing. However, little is known about the role of the BLA endocannabinoid system in aversive memories. Additionally, BLA endocannabinoid transmission seems to be related to emotional states, but the relevance of these effects to memory formation is still unknown. In this study we investigated the effects of the eCB anandamide (AEA) and the CB1 antagonist/inverse agonist AM251 infused into the BLA on the acquisition of an aversive memory task, concomitantly evaluating basal anxiety levels in rats. Male rats received pre-training micro-injection of AEA, AM251 or vehicle bilaterally into the BLA, and were studied with the plus-maze discriminative avoidance task (a paradigm that allows concomitant and independent evaluation of anxiety-like behavior and the memory of an aversive task). Our results showed that AEA into the BLA before training prevented memory retrieval 24 h later, as evaluated by exploration of the aversive arm of the maze, while AM251 into the BLA did not interfere with animals' performance. In addition, AEA had no effect on anxiety-like behavior (as evaluated by open arm exploration and risk assessment), while AM251 induced an anxiogenic effect. Our data indicate an important role of BLA CB1 receptors in aversive memory formation, and suggest that this involvement is not necessarily related to a possible modulation of anxiety states.  相似文献   
152.
The aim of this study was to analyze the relationship between personal values and well-being. Two correlational studies are presented with the following random samples: (1) four native samples: two samples from the 2006 European Social Survey (Europe n1 = 28,375, Spain n2 = 1,321) and two Basque samples (n3 = 1,770; n4 = 820); and (2) a sample of immigrants in the Basque Country (quasirandom) (n5 = 1,171). Age range of respondents was 18–60 years. The instruments used were for measuring: (1) personal values (Schwartz’s PVQ-40 or PVQ-21), and (2) well-being (Bradburn’s PNA, Goldberg’s GHQ, and life satisfaction and perceived control items from the World Value Survey). Partial correlation analysis was applied, with PVQ scale response bias controlled. The data supported a positive association of hedonic and psychological well-being with openness to experience and individualist values, and a negative association with power and conservation or collectivist values. Satisfaction with life partially mediated the relationship between personal values and affect. The results support a universal association of healthy values with well-being.  相似文献   
153.
We studied the efficacy and implementation outcomes of a culturally responsive parent training (PT) program. Fifty-four Chinese American parents participated in a wait-list controlled group randomized trial (32 immediate treatment, 22 delayed treatment) of a 14-week intervention designed to address the needs of high-risk immigrant families. Parents were eligible for intervention if they were Chinese-speaking immigrants referred from schools, community clinics, or child protective services with concerns about parenting or child behavior problems. Retention and engagement were high with 83% of families attending 10 or more sessions. Results revealed that the treatment was efficacious in reducing negative discipline, increasing positive parenting, and decreasing child externalizing and internalizing problems. Treatment effects were larger among families with higher levels of baseline behavior problems and lower levels of parenting stress. Further augmentation of PT to address immigrant parent stress may be warranted. Qualitative impressions from group leaders suggested that slower pacing and increased rehearsal of skills may improve efficacy for immigrant parents unfamiliar with skills introduced in PT.  相似文献   
154.
Development and validation of a questionnaire about the main variables affecting the individual investor's behavior in the Stock Exchange. There is a considerable lack of information about the methodology usually used in most of the studies about individual investor's behavior. The studies reviewed do not show the method used in the selection of the items or the psychometric properties of the questionnaires. Because of the importance of investment in the Stock Exchange nowadays, it seems relevant to obtain a reliable instrument to understand individual investor's behavior in the Stock Exchange. Therefore, the goal of the present work is to validate a questionnaire about the main variables involved in individual investors' behavior in the Stock Exchange. Based on previous studies, we elaborated a questionnaire using the Delphi methodology with a group of experts. The internal consistency (Cronbach alpha=.934) and validity evidence of the questionnaire show that it may be an effective instrument and can be applied with some assurance.  相似文献   
155.
This paper provides information about the efficacy of a tutorial training program intended to enhance elementary fifth graders' study processes and foster their deep approaches to learning. The program "Testas's (mis)adventures" consists of a set of books in which Testas, a typical student, reveals and reflects upon his life experiences during school years. These life stories are nothing but an opportunity to present and train a wide range of learning strategies and self-regulatory processes, designed to insure students' deeper preparation for present and future learning challenges. The program has been developed along a school year, in a one hour weekly tutorial sessions. The training program had a semi-experimental design, included an experimental group (n=50) and a control one (n=50), and used pre- and posttest measures (learning strategies' declarative knowledge, learning approaches and academic achievement). Data suggest that the students enrolled in the training program, comparing with students in the control group, showed a significant improvement in their declarative knowledge of learning strategies and in their deep approach to learning, consequently lowering their use of a surface approach. In spite of this, in what concerns to academic achievement, no statistically significant differences have been found.  相似文献   
156.
There are few studies on the development of anxiety and depression in orthopaedics and trauma (O&T) inpatients. We designed a cross-sectional study aimed at comparing the prevalence of depression and anxiety in 100 O&T inpatients and 100 clinical inpatients in the same hospital. O&T patients were divided into subgroups: trauma and non-trauma (arthroplasty, tumour, and infection sub grouping). We measured anxiety and depression by the Hospital Anxiety and Depression Scale and co-morbidities by the Charlson age-adjusted comorbidity index (CCI). For the trauma subgroup, AO/OTA fracture classification and Gustillo and Anderson grade of open fractures classification was applied. The prevalence of anxiety and depression was 35% and 28%, respectively for the clinical sample, and 44% and 33% for the O&T sample. Compared with the clinical sample, anxiety scores were higher in the O&T sample (p = .047), and in arthroplasty (p = .020) and trauma subgroups (p = .031). In the O&T sample, high CCI scores were associated with high anxiety scores (p = .033).  相似文献   
157.
In this paper, we describe a digital scenario where we simulated the emergence of self-organized symbol-based communication among artificial creatures inhabiting a virtual world of unpredictable predatory events. In our experiment, creatures are autonomous agents that learn symbolic relations in an unsupervised manner, with no explicit feedback, and are able to engage in dynamical and autonomous communicative interactions with other creatures, even simultaneously. In order to synthesize a behavioral ecology and infer the minimum organizational constraints for the design of our creatures, we examined the well-studied case of communication in vervet monkeys. Our results show that the creatures, assuming the role of sign users and learners, behave collectively as a complex adaptive system, where self-organized communicative interactions play a major role in the emergence of symbol-based communication. We also strive in this paper for a careful use of the theoretical concepts involved, including the concepts of symbol and emergence, and we make use of a multi-level model for explaining the emergence of symbols in semiotic systems as a basis for the interpretation of inter-level relationships in the semiotic processes we are studying.  相似文献   
158.
Age differences in emotional experience are assessed through self-report scales or questionnaires referring to a specific period of varying length, and examining different parameters of emotional response. A recent meta-analysis suggests that the type of instrument and parameter used could account for some of the inconsistencies in the results. The present study shows comparisons between emotional experience in samples of younger (N = 120, aged 20–27) and older (N = 103, aged 55–75) participants. An Emotional Self-Monitoring record was administered every day for a week. The results show that emotional expression was highly stable over time. However, they also show that some theoretical assumptions about individual age differences in emotional experience and age depend on the parameters on which the analysis is based (occurrence, frequency and intensity, and emotional balance).  相似文献   
159.
The present study explores whether endogenous attention can modulate body perception. A modified version of the Posner paradigm was used to direct participants' attention toward the appearance of distinct body images, which differed only in detailed idiosyncratic features: one's own and another person's hands. Hand stimuli were preceded by symbolic cues that predicted their identity with high probability, which made it possible to compare the processing of expected (valid) and unexpected (invalid) targets. Results revealed that endogenous attention influenced the processing of participants' own hands by speeding participants' responses to valid in contrast to invalid trials. Crucially, no validity effect was found for the hands of another person. These findings cannot be explained in terms of perceptual familiarity, since an optimization of the processing for both familiar and unfamiliar faces by symbolic cues was observed. In light of these results, it is suggested that participants are able to anticipate particular stimuli within the same perceptual category as long as these stimuli appear to be remarkably distinct to them, which is probably the case for particular faces and their own bodies, in contrast to other people's bodies.  相似文献   
160.
This study examined effectiveness of Home‐Start, a program designed to support parents with young children. The aims were (a) to examine whether Home‐Start improved maternal well‐being and (b) to examine whether Home‐Start led to changes in the behavior of mothers or children. Self‐reported and observational data were collected in two waves, using data from 54 mothers and their children between 1.5 and 3.5 years of age who participated in this intervention program for 6 months. These data were compared to 51 comparison families who reported need for parenting support. The results showed a significant improvement in perceived parenting competence, but no effects on maternal depressive moods. Mixed results were found for parenting behavior: Parental consistency and observed sensitivity improved significantly in the Home‐Start group whereas no effects were found on the other parenting variables. Child behavioral problems seemed to diminish at the second measurement in both groups, and therefore these changes cannot be attributed to Home‐Start.  相似文献   
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