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981.
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   
982.
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   
983.
This article uses a general latent variable framework to study a series of models for nonignorable missingness due to dropout. Nonignorable missing data modeling acknowledges that missingness may depend not only on covariates and observed outcomes at previous time points as with the standard missing at random assumption, but also on latent variables such as values that would have been observed (missing outcomes), developmental trends (growth factors), and qualitatively different types of development (latent trajectory classes). These alternative predictors of missing data can be explored in a general latent variable framework with the Mplus program. A flexible new model uses an extended pattern-mixture approach where missingness is a function of latent dropout classes in combination with growth mixture modeling. A new selection model not only allows an influence of the outcomes on missingness but allows this influence to vary across classes. Model selection is discussed. The missing data models are applied to longitudinal data from the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study, the largest antidepressant clinical trial in the United States to date. Despite the importance of this trial, STAR*D growth model analyses using nonignorable missing data techniques have not been explored until now. The STAR*D data are shown to feature distinct trajectory classes, including a low class corresponding to substantial improvement in depression, a minority class with a U-shaped curve corresponding to transient improvement, and a high class corresponding to no improvement. The analyses provide a new way to assess drug efficiency in the presence of dropout.  相似文献   
984.
This paper examines the association of cardiovascular reactivity with thermal thresholds (detection and unpleasantness). Heart period (HP), systolic (SBP) and diastolic (DBP) blood pressure of 42 health young males were recorded during a cardiovascular reactivity task (a videogame based upon Sidman's avoidance paradigm). Thermal sensitivity, assessing detection and unpleasantness thresholds with radiant heat in the forearm was also estimated for participants. Participants with differential scores in the cardiovascular variables from base line to task > or = P65 were considered as reactors and those how have differential scores < or = P35 were considered as non-reactors. Significant differences were observed between groups in the unpleasantness thresholds in blood pressure (BP) but not in HP. Reactors exhibited significant higher unpleasantness thresholds than non-reactors. No significant differences were obtained in detection thresholds between groups.  相似文献   
985.
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   
986.
The reading achievement of children and adolescents with Attention Deficit Hyperactivity Disorder (ADHD) has scarcely been explored in research conducted in the Spanish language and when it has, the results have been contradictory. The focus of the present research is to analyze participants' reading competency and metacognitive strategies as they carry out reading comprehension tasks. The sample was comprised of 187 Argentine schoolchildren aged 9 to 13 years old. 94 constituted the control group and the clinical group consisted of 93 schoolchildren diagnosed with ADHD. The metacognitive assessment was made up of two metacognitive tests, the Reading Awareness Scale (ESCOLA; acronym in Spanish) and a Spanish adaptation of Metacognitive Awareness of Reading Strategies Inventory (MARSI), and one test of reading comprehension, the Evaluation of Reading Processes for Secondary Education Students (PROLEC-SE; acronym in Spanish). Students with ADHD had lower achievement on tests o reading comprehension compared to the control group. Nevertheless, our results suggest their difficulties did not stem from readin comprehension problems, but rather from alterations in their Executive Functions, because when subjects' reading comprehensio was equalized, students with ADHD still exhibited a lower level of Metacognition, particularly when it came to planning.  相似文献   
987.
988.
Menopause is associated with a considerable variety of physical, psychological and social symptoms that can be treated using cognitive-behavioral techniques. In the present study, 21 women took part in an eight-week group intervention consisting of weekly two-hour sessions to address their slight symptoms related to the climacteric stage of life. The intervention included: psycho education on menopause, relaxation techniques, nutrition and fitness exercises, Kegel exercises, and problem-solving techniques. A control group was included that did not receive treatment and consisted of 28 women. The results revealed a significant reduction in most symptoms (including depression and anxiety) after intervention as compared to the baseline period. No changes appeared in the control group. The relevance of this work lies in the potential element of prevention this therapeutic package could offer to relieve various symptoms, slight and incipient, during the perimenopausal stage.  相似文献   
989.
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   
990.
The existence of domestic violence is closely linked to several ideological factors that include sexism and other beliefs about society in general, namely the belief in a just world. In this study, which involved 485 people of both sexes aged between 18 and 70 years, we analyzed the influence of these ideological variables of the perceivers and characteristics of the situation on judgments of a gender aggression--blaming the victim and exonerating the perpetrator. Results showed differences in the reactions of observers depending on the cause that triggered the aggression. Participants blamed the victim and exonerated the aggressor more when no cause of the aggression was mentioned than when a cause was mentioned (the woman wanted to separate, to see an old male friend, or simply to take a trip with her female friends). We also found clear effects of hostile sexism and just world beliefs on the dependent variables. Results showed that the influence of just world beliefs depended on the fact of mention or not a cause for the aggression.  相似文献   
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