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931.
María Isabel Peralta-Ramírez A. Verdejo M. A. Muñoz J. M. Sabio J. F. Jiménez-Alonso M. Pérez-García 《Journal of clinical psychology in medical settings》2007,14(4):344-350
The goal of this study was to develop a simple, easy, and quick self-report measure, the Lupus Symptom Inventory (LSI), designed
to evaluate subjective symptoms of Systemic Lupus Erythematosus (SLE). The internal consistency of the LSI was tested, as
well as its concordance with physician reports and serological indicators of disease activity by evaluating the self-reports
of 46 patients with SLE who completed the LSI daily for a one-month period. Throughout this one-month period, parameters of
serological activity and routine medical check-up were obtained. The results showed a high internal consistency of the LSI,
with a Cronbach alpha of .86. Additionally, a contingency analysis showed agreement between medical report and patient self-report
on the same day for six of seven lupus symptoms (difficulty breathing (p < .004), joint pain (p < .001), loss of appetite (p < .003), general malaise (p < .005), fatigue (p < .005), and skin rash (p < .018)) but not for abdominal symptoms. Finally, differences were found between LSI scores of patients with high versus
low serological activity (χ2(1) = 5.302; p < .021), with the former presenting higher LSI scores than the latter. These results show that the LSI may be a reliable
and valid instrument for evaluating the subjective symptoms of the disease as well as its fluctuations. 相似文献
932.
Forcato C Burgos VL Argibay PF Molina VA Pedreira ME Maldonado H 《Learning & memory (Cold Spring Harbor, N.Y.)》2007,14(4):295-303
The reconsolidation hypothesis states that a consolidated memory could again become unstable and susceptible to facilitation or impairment for a discrete period of time after a reminder presentation. The phenomenon has been demonstrated in very diverse species and types of memory, including the human procedural memory of a motor skill task but not the human declarative one. Here we provide evidence for both consolidation and reconsolidation in a paired-associate learning (i.e., learning an association between a cue syllable and the respective response syllable). Subjects were given two training sessions with a 24-h interval on distinct verbal material, and afterward, they received at testing two successive retrievals corresponding to the first and second learning, respectively. Two main results are noted. First, the first acquired memory was impaired when a reminder was presented 5 min before the second training (reconsolidation), and also when the second training was given 5 min instead of 24 h after the first one (consolidation). Second, the first retrieval proved to influence negatively on the later one (the retrieval-induced forgetting [RIF] effect), and we used the absence of this RIF effect as a very indicator of the target memory impairment. We consider the demonstration of reconsolidation in human declarative memory as backing the universality of this phenomenon and having potential clinical relevance. On the other hand, we discuss the possibility of using the human declarative memory as a model to address several key topics of the reconsolidation hypothesis. 相似文献
933.
Experiences with a high emotional content (aversive) tend to be stored as long-term memories; however, there are also contextual recollections, which form a significant part of our memories. Different research has shown that the insular cortex (IC) plays an important role during aversive memory formation, yet its role during incidental/non-aversive learning like pre-exposure contextual memory formation has received little attention. The objective of this research was to establish the role of cholinergic activity in the IC through its muscarinic receptors during the formation of inhibitory avoidance (IA) memory, as well as during pre-exposure contextual memory, using a paradigm such as latent inhibition (LI). Rats with bilateral cannulae directed into the IC were trained in the LI paradigm of IA or IA task alone. The muscarinic antagonist receptor scopolamine was infused bilaterally into the IC 5 min before the pre-exposure into the dark chamber of the IA cage, one day before the conventional IA training or during the IA training day. During the IA test, the entrance latency into the dark chamber of the IA cage was measured as an index of contextual memory. The results showed that scopolamine infused before and after IA training disrupts inhibitory avoidance memory. Also, it showed that the pre-exposed saline-infused animals (LI) had a lower entrance latency compared to the group not pre-exposed (IA). However, the group that received scopolamine into the IC before, but not after, the pre-exposure to the dark chamber, presented a similar latency to the IA group, showing a blockade of the latent inhibition of the IA. These results suggest that cholinergic activity in the insular cortex is necessary during the acquisition and consolidation of avoidance memory, but appears necessary only during the acquisition of pre-exposure non-aversive contextual memory. 相似文献
934.
Andero R Torras-Garcia M Quiroz-Padilla MF Costa-Miserachs D Coll-Andreu M 《Neurobiology of learning and memory》2007,87(4):510-521
The pedunculopontine tegmental nucleus (PPTg) is involved in the regulation of thalamocortical transmission and of several functions related to ventral and dorsal striatal circuits. Stimulation of the PPTg in anesthetized animals increases cortical arousal, cortical acetylcholine release, bursting activity of mesopontine dopaminergic cells, and striatal dopamine release. It was hypothetized that PPTg stimulation could improve learning by enhancing cortical arousal and optimizing the activity of striatal circuits. We tested whether electrical stimulation (ES) of the PPTg, applied to freely-moving awake rats previously implanted with a chronic electrode, would improve the acquisition and/or the retention of two-way active avoidance conditioning, and whether this effect would depend on the specific PPTg region stimulated (anterior vs posterior) and on the time of ES: just before (pre-training) or after (post-training) each of three training sessions. The treatment consisted of 20 min of ES (0.2 ms pulses at 100 Hz; current intensity: 40-80 microA). The results showed that (1) this stimulation did not induce either any signs of distress nor abnormal behaviors, apart from some motor stereotyped behaviors that disappeared when current intensity was lowered; (2) pre-training ES applied to the anterior PPTg improved the acquisition of two-way active avoidance, (3) no learning improvement was found after either post-training ES of the anterior PPTg, or pre- and post-training ES of the posterior PPTg. The results give support to a role of PPTg in learning-related processes, and point to the existence of functional PPTg regions. 相似文献
935.
Bekinschtein P Katche C Slipczuk LN Igaz LM Cammarota M Izquierdo I Medina JH 《Neurobiology of learning and memory》2007,87(2):303-307
It is widely accepted that the formation of long-term memory (LTM) requires mRNA translation, but little is known about the cellular mechanisms in the brain that regulate this process. Mammalian target of rapamycin (mTOR) is a key regulator of translational efficacy and capacity. Here, we show that LTM formation of one-trial inhibitory avoidance (IA) in rats, a hippocampus-dependent fear-motivated learning task, requires mTOR activation. IA training is specifically associated with a rapid increase in the phosphorylation state of mTOR and its substrate ribosomal S6 kinase (p70S6K). Bilateral intra-CA1 infusion of rapamycin, a selective mTOR inhibitor, 15 min before, but not immediately after training completely hinders IA LTM without affecting short-term memory (STM) retention. Therefore, our findings indicate that the regulation of hippocampal mRNA translation is a major control step in memory consolidation. 相似文献
936.
Burgos JE 《Journal of the experimental analysis of behavior》2007,88(1):115-130
This article presents an interpretation of autoshaping, and positive and negative automaintenance, based on a neural-network model. The model makes no distinction between operant and respondent learning mechanisms, and takes into account knowledge of hippocampal and dopaminergic systems. Four simulations were run, each one using an A-B-A design and four instances of feedfoward architectures. In A, networks received a positive contingency between inputs that simulated a conditioned stimulus (CS) and an input that simulated an unconditioned stimulus (US). Responding was simulated as an output activation that was neither elicited by nor required for the US. B was an omission-training procedure. Response directedness was defined as sensory feedback from responding, simulated as a dependence of other inputs on responding. In Simulation 1, the phenomena were simulated with a fully connected architecture and maximally intense response feedback. The other simulations used a partially connected architecture without competition between CS and response feedback. In Simulation 2, a maximally intense feedback resulted in substantial autoshaping and automaintenance. In Simulation 3, eliminating response feedback interfered substantially with autoshaping and automaintenance. In Simulation 4, intermediate autoshaping and automaintenance resulted from an intermediate response feedback. Implications for the operant-respondent distinction and the behavior-neuroscience relation are discussed. 相似文献
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940.
In this article, a leadership model is presented, with which to investigate the relationship of trait emotional intelligence (trait EI), leadership self-efficacy and leader's task self-efficacy with collective task efficacy and group performance. The sample was made up of 217 undergraduate students, randomly assigned to work teams of 1 leader and 2 followers that were requested to perform a production task. An adapted version of the Schutte Self-Report Inventory (SSRI; Schutte et al., 1998) was used to measure trait EI. Structural equation modeling was used to test the hypothesized relationships. Results indicated that task self-efficacy was a mediator between leadership self-efficacy and collective task efficacy; the latter, in turn, was the best predictor of group performance. No significant relationship was found between trait EI and collective task efficacy although, unexpectedly, trait EI was positively associated with leadership self-efficacy. Implications of the results are discussed. 相似文献