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991.
Martínez MC Alen N Ballarini F Moncada D Viola H 《Neurobiology of learning and memory》2012,98(2):165-173
Recently encoded information can be lost in the presence of new information, a process called 'retrograde interference'. Retrograde interference has been extensively described for more than a century; however, little is known about its underlying mechanisms. Different approaches agree on the need of the synthesis of plasticity related proteins (PRPs) to consolidate a long-term memory (LTM). Our hypothesis is that when PRPs are limited, interference of a task over LTM formation of another may be due to the utilization of protein resources common to both tasks. Here, by combining the tasks of inhibitory avoidance (IA) and open field (OF) exploration in rats, we show that memory traces compete for their stabilization if PRPs are limited. As a result, LTM is formed for only one of the tasks with a consequent decrease in the memory for the other. Furthermore, infusing Arc antisense oligonucleotide into the dorsal hippocampus, we found that Arc is necessary for LTM formation of these two types of learning tasks and is one of the PRPs that can be shared between them when animals are trained in both OF and IA. In sum, these findings suggest that under conditions of reduced protein availability, a learning task interferes with LTM formation of another by using the available PRPs. 相似文献
992.
Klappenbach M Maldonado H Locatelli F Kaczer L 《Learning & memory (Cold Spring Harbor, N.Y.)》2012,19(2):73-83
The understanding of how the reinforcement is represented in the central nervous system during memory formation is a current issue in neurobiology. Several studies in insects provide evidence of the instructive role of biogenic amines during the learning and memory process. In insects it was widely accepted that dopamine (DA) mediates aversive reinforcements. However, the idea of DA being exclusively involved in aversive memory has been challenged in recent studies. Here, we study the involvement of DA during aversive and appetitive memories in the crab Chasmagnathus. We found that DA-receptor antagonists impair aversive memory consolidation, in agreement with previous reports in insects, while administration of DA facilitates memory formation after a weak training protocol. In contrast, DA treatment during appetitive training was found to impair formation of long-term appetitive memory. In addition, as a first step in elucidating the neuroanatomical correlates of DA action on memory, we mapped dopaminergic neurons in the central nervous system of the crab. Results of the current study, together with those obtained in a previous work about the role of octopamine (OA), suggest that both amines (DA and OA) play a dual action in memory processes. On the one hand, DA and OA mediate the aversive and the appetitive signals, respectively, throughout training, while on the other hand, they interfere with the formation of memory of the opposite sign (DA in appetitive and OA in aversive). Our results support a new understanding about the way appetitive and aversive stimuli are processed during memory formation to ensure adaptive behavior. 相似文献
993.
Sepúlveda AR Anastasiadou D del María RA Graell M 《The Spanish journal of psychology》2012,15(2):825-839
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
994.
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
995.
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
996.
de Oliveira IR Hemmany C Powell VB Bonfim TD Duran EP Novais N Velasquez M Di Sarno E Alves GL Cesnik JA 《CNS spectrums》2012,17(1):16-23
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
997.
Osilla KC D'Amico EJ Díaz-Fuentes CM Lara M Watkins KE 《Cultural diversity & ethnic minority psychology》2012,18(2):192-202
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
998.
Since modernity, the concept of subject supposes both an anthropocentric and a dualistic view of life and reality. In this study, we carry out an analytic interpretation of the Descartes’ notion of subject, in order to build a different dimension of the concept of subject. We discuss the activity of computing, as the manner by which the living subject relates with and in-forms the world. We further examine computing in the aging yeast as an example of living subject and we try to comprehend the maturity of the subjectivity in Descartes’ res cogitans and in our proposed res computans. 相似文献
999.
An experiment was conducted using a human instrumental learning task with the goal of evaluating the mechanisms underlying the deleterious effect of context-switching on responding to an unambiguous stimulus when contexts are informative to solve the task. Participants were trained in a context-based reversal discrimination in which two discriminative stimuli (X and Y) interchange their meaning across contexts A and B. In context A, discriminative stimulus Z consistently announced that the relationship between a specific instrumental response (RI) and a specific outcome (O1) was in effect. Performance in the presence of stimulus Z was equally deteriorated when the test was conducted outside the training context, regardless of whether the test context was familiar (context B) or new (context C). This result is consistent with the idea that participants code all the information presented in an informative context as context-specific with the context playing a role akin to an occasion setter. 相似文献
1000.
This review systematically investigates rates of physical intimate partner violence for both sexes in international samples. Surveys that accessed nationally representative samples, used gender inclusive methodology and neutral contexts are reviewed to determine 12-month and lifetime victimization and perpetration rates. Discrepancies between international rates, and the impact that gender equality may have upon these differences is also investigated. Electronic databases were systematically searched to identify surveys that met inclusion criteria. Eleven surveys were reviewed. Of these, Family Violence surveys had the highest methodological quality and showed equal rates for both sexes. Surveys of lesser quality typically showed higher female victimization and male perpetration rates. Countries at the extremes of gender empowerment measure scores differed in their patterns of rates. Gender equality in the US was associated with symmetry for the sexes, and inequality in Uganda associated with higher female victimization. However, as countries tended to use different methods to investigate the problem it was not possible to compare the effects of gender equality on differences in international rates of IPV. It is concluded that survey methodology needs to be consistent across nations, and specifically target family violence if true rates are to be determined and compared across the globe. 相似文献