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941.
The ability of neurons to modify their synaptic strength in an activity-dependent manner has a crucial role in learning and memory processes. It has been proposed that homeostatic forms of plasticity might provide the global regulation necessary to maintain synaptic strength and plasticity within a functional dynamic range. Similarly, it is considered that the capacity of synapses to express plastic changes is itself subject to variation dependent on previous experience. In particular, training in several behavioral tasks modifies the possibility to induce long-term potentiation (LTP). Our previous studies in the insular cortex (IC) have shown that induction of LTP in the basolateral amygdaloid nucleus (Bla)-IC projection previous to conditioned taste aversion (CTA) training enhances the retention of this task. The aim of the present study was to analyze whether CTA training modifies the ability to induce subsequent LTP in the Bla-IC projection in vivo. Thus, CTA trained rats received high frequency stimulation in the Bla-IC projection in order to induce LTP 48, 72, 96 and 120 h after the aversion test. Our results show that CTA training prevents the subsequent induction of LTP in the Bla-IC projection, for at least 120 h after CTA training. We also showed that pharmacological inhibition of CTA consolidation with anisomycin (1 μl/side; 100 μg/μl) prevents the CTA effect on IC-LTP. These findings reveal that CTA training produces a persistent change in the ability to induce subsequent LTP in the Bla-IC projection in a protein-synthesis dependent manner, suggesting that changes in the ability to induce subsequent synaptic plasticity contribute to the formation and persistence of aversive memories.  相似文献   
942.
Variation in intracellular calcium concentration regulates the induction of long-term synaptic plasticity and is associated with a variety of memory/retrieval and learning paradigms. Accordingly, impaired calcium mobilization from internal deposits affects synaptic plasticity and cognition in the aged brain. During taste memory formation several proteins are modulated directly or indirectly by calcium, and recent evidence suggests the importance of calcium buffering and the role of intracellular calcium deposits during cognitive processes. Thus, the main goal of this research was to study the consequence of hampering changes in cytoplasmic calcium and inhibiting SERCA activity by BAPTA-AM and thapsigargin treatments, respectively, in the insular cortex during different stages of taste memory formation. Using conditioned taste aversion (CTA), we found differential effects of BAPTA-AM and thapsigargin infusions before and after gustatory stimulation, as well as during taste aversive memory consolidation; BAPTA-AM, but not thapsigargin, attenuates acquisition and/or consolidation of CTA, but neither compound affects taste aversive memory retrieval. These results point to the importance of intracellular calcium dynamics in the insular cortex during different stages of taste aversive memory formation.  相似文献   
943.
Recently there has been a semantic shift in the pornographic word ‘cum.’ Traditionally, the word, as a noun, is used to designate semen. However, ‘cum’ is now used to designate also female fluids during sexual activity. The concept of ‘female cum’ is discussed in relation to examples from a corpus of two hundred erotic short stories collected from the Internet, and to the physiological realities of female fluids during sex. In order to show how the innovation of ‘female cum’ is useful in written erotic narrative, a comparison is made with filmed pornography and drawn erotic comics. Finally, I argue that ‘cum’ in this new context is used as a device to arouse sexual excitement.  相似文献   
944.
This article provides and introduction to the 2011 National Multicultural Conference & Summit Keynote Addresses. The authors explain that they chose to focus on the tension and possibilities within multicultural psychology at the seventh biennial National Multicultural Conference & Summit (NMCS), which was held on January 27-28, 2011, at The Westin-Seattle Hotel. During the 2-day conference, nearly 900 attendees engaged with one another and heard from experts in the field as we focused on the theme, "Unification through Diversity: Bridging Psychological Science & Practice in the Public Interest. Two key sets of presentations are highlighted.  相似文献   
945.
The quality of infant-mother attachment has been linked to competence in different domains of child development. Research indicates that early intervention can enhance the quality of infant-mother attachment, though its efficacy in a group format has yet to be evaluated. The current study is aimed at examining the usefulness of a group intervention in enhancing infant-mother attachment. An intervention aimed at addressing aspects such as maternal responsivity, sensitivity and childrearing behaviour was developed by the researchers and experienced psychologists. The intervention spanned a period of 14 months starting from the third quarter of pregnancy. The intervention was evaluated among 24 mothers from the Basque region of Spain. The sample consisted of children of both genders in a similar proportion: 45.8% were boys and 54.2% were girls. The children in this sample were full-term born and did not present symptoms of any serious pre- or postnatal complications. The intervention had a statistically non-significant medium effect. Infants whose mothers had received the intervention showed higher rates of secure attachment compared to children from the control group, as assessed by the Strange Situation observation procedure. A potentially significant confounding variable, maternal attachment, was balanced across the intervention and comparison groups. We can tentatively point out that a group intervention may enhance the quality of infant-mother attachment. Nevertheless, because the study design was not randomized, the results of this study remain preliminary and need replication in a full randomized controlled trial designed study.  相似文献   
946.
Risk propensity is the stable tendency to choose options with a lower probability of success, but greater rewards. Its evaluation has been approached from various perspectives: from self-report questionnaires to objective tests. Self-report questionnaires have often been criticized due to interference from voluntary and involuntary biases, in addition to their lack of predictive value. Objective tests, on the other hand, require resources that make them difficult to administer to large samples. This paper presents an easy-to-administer, 30-item risk propensity test. Each item is itself an objective test describing a hypothetical situation in which the subject must choose between three options, each with a different gain function but equivalent in expected value. To assess its psychometric fit, the questionnaire was administered to 222 subjects, and we performed a test of its reliability as well as exploratory factor analysis. The results supported a three-factor model of risk (Sports and Gambling, Long-term Plans, and Loss Management). After making the necessary adjustments and incorporating a global factor of risk propensity, confirmatory factor analysis was done, revealing that the data exhibited adequate goodness of fit.  相似文献   
947.
948.
This study assessed the impact of a school-based program aimed at preventing disordered eating. The program was based on the media-literacy approach and has interactive format. The program was assessed under strong methodological conditions. Seven schools with 263 Spanish adolescent girls in the area of Barcelona, were randomly assigned to either the complete prevention program condition, the partial program condition or the non-treatment control condition, and assessed at pre, post and 6-month follow-up. The program was effective in generating positive changes at follow-up. The effects sizes (ES(d) = 0.29 to ES(d) = 0.38) were greater, on average, than that obtained up to now in selective-universal programs, and similar or greater than that achieved by targeted prevention programs. The results indicate a greater and relevant effect size of the intervention in those participants who completed the inter-session interactive activities (ES(d) = 0.29 to ES(d) = 0.45) although the differences were not significant. These results suggest the importance of monitoring adherence to the activities in all programs defined as "interactive". The implications and limitations of this study are discussed.  相似文献   
949.
The aim of this paper was to develop an instrument to assess levels of stress experienced by Latin-American immigrants in their acculturative process in Spain. A sample of 692 immigrants from Latin America, aged 20 to 63 years, took part on this study (54.9% males and 45.1% females). A 24-item questionnaire with high reliability (.92) was elaborated. Six factors related to acculturative stress were found: 1) discrimination and rejection; 2) differences with the out-group (native Spaniards); 3) citizenship problems and legality; 4) problems concerning social relationships with other immigrants; 5) nostalgia and longing; and 6) family break-up. Our findings show that participants have a high level of stress related to nostalgia and longing, family break-up, and the perception of discrimination and rejection by natives. The usefulness of the instrument and its applications and restrictions are discussed.  相似文献   
950.
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