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311.
Induction of lucid dreams: A systematic review of evidence 总被引:1,自引:0,他引:1
In lucid dreams the dreamer is aware of dreaming and often able to influence the ongoing dream content. Lucid dreaming is a learnable skill and a variety of techniques is suggested for lucid dreaming induction. This systematic review evaluated the evidence for the effectiveness of induction techniques. A comprehensive literature search was carried out in biomedical databases and specific resources. Thirty-five studies were included in the analysis (11 sleep laboratory and 24 field studies), of which 26 employed cognitive techniques, 11 external stimulation and one drug application. The methodological quality of the included studies was relatively low. None of the induction techniques were verified to induce lucid dreams reliably and consistently, although some of them look promising. On the basis of the reviewed studies, a taxonomy of lucid dream induction methods is presented. Several methodological issues are discussed and further directions for future studies are proposed. 相似文献
312.
Rodrigues CS de Oliveira VZ Camargo G Osório CM de Castilhos RM Saraiva-Pereira ML Schuler-Faccini L Jardim LB 《Journal of genetic counseling》2012,21(1):101-112
Diagnostic tests are available to detect several mutations related to adult-onset, autosomal dominant, neurodegenerative diseases.
We aimed to describe our experience in a presymptomatic testing program run by the Brazilian Public Health System from 1999
to 2009. A total of 184 individuals were eligible for presymptomatic testing due to a risk for spinocerebellar ataxia (SCA)
- SCA3 (80%), Huntington’s disease (11.9%), familial amyloidotic neuropathy (4.3%), SCA1, SCA2, SCA6, or SCA7. Most were women
(70%), married (54%), and had children prior to presymptomatic testing (67%). Their mean age at entrance was 34 (SD = 11 years).
Educational level was above the average Brazilian standard. After receipt of genetic counseling, 100 individuals (54%) decided
to undergo testing; of these, 51 were carriers. Since no individual returned for post-test psychological evaluation, we conducted
a subsequent survey, unrelated to test disclosures. We contacted 57 individuals of whom 31 agreed to participate (24 had been
tested, 7 had not). Several ascertainment concerns relating to these numerous losses prevented us from generalizing our results
from this second survey. We concluded that: decision-making regarding presymptomatic testing seems to be genuinely autonomous,
since after genetic counseling half the individuals who asked for presymptomatic testing decided in favor and half decided
against it; general characteristics of Brazilians who sought presymptomatic testing were similar to many European samples
studied previously; and individuals at risk for SCA3 may be at greater risk of depression. Although no clear-cut reason emerged
for rejection of follow-up psychological sessions after presymptomatic testing, this finding suggests adjustments to our presymptomatic
testing program are necessary. 相似文献
313.
Using two clinical samples of patients, the presented studies examined the construct validity of the recently revised Anxiety Sensitivity Index-3 (ASI-3). Confirmatory factor analyses established a clear three-factor structure that corresponds to the postulated subdivision of the construct into correlated somatic, social, and cognitive components. Participants with different primary clinical diagnoses differed from each other on the ASI-3 subscales in theoretically meaningful ways. Specifically, the ASI-3 successfully discriminated patients with anxiety disorders from patients with nonanxiety disorders. Moreover, patients with panic disorder or agoraphobia manifested more somatic concerns than patients with other anxiety disorders and patients with nonanxiety disorders. Finally, correlations of the ASI-3 scales with other measures of clinical symptoms and negative affect substantiated convergent and discriminant validity. Substantial positive correlations were found between the ASI-3 Somatic Concerns and body vigilance, between Social Concerns and fear of negative evaluation and socially inhibited behavior, and between Cognitive Concerns and depression symptoms, anxiety, fear of negative evaluation, and subjective complaints. Moreover, Social Concerns correlated negatively with dominant and intrusive behavior. Results are discussed with respect to the contribution of the ASI-3 to the assessment of anxiety-related disorders. 相似文献
314.
The factor structure, internal consistency, construct validity, and predictive validity of the Dutch version of the Five Facet Mindfulness Questionnaire (FFMQ-NL) were studied in a sample of meditators (n = 288) and nonmeditators (n = 451). A five-factor structure was demonstrated in both samples, and the FFMQ-NL and its subscales were shown to have good internal consistencies. Meditators scored higher on all facets of the FFMQ-NL than the participants in the nonmeditating sample. For both samples, expected negative correlations between most mindfulness facets (all except for the Observing facet) and the constructs of alexithymia, thought suppression, rumination, worry, and dissociation were found. The Observing facet of the FFMQ-NL showed an unexpected positive correlation with thought suppression in the nonmeditating sample. Furthermore, as expected, mindfulness facets were negatively related to psychological symptoms, and all mindfulness facets except for Observing and Describing significantly predicted psychological symptoms. Overall, the Dutch FFMQ demonstrated favorable psychometric properties, commensurate with its (original) English language version. 相似文献
315.
Major brain functions depend on neuronal processes that favor the plasticity of neuronal circuits while at the same time maintaining their stability. The mechanisms that regulate brain plasticity are complex and engage multiple cascades of molecular components that modulate synaptic efficacy. Protein kinases (PKs) and phosphatases (PPs) are among the most important of these components that act as positive and negative regulators of neuronal signaling and plasticity, respectively. In these cascades, the PP protein phosphatase 2B or calcineurin (CaN) is of particular interest because it is the only Ca(2+)-activated PP in the brain and a major regulator of key proteins essential for synaptic transmission and neuronal excitability. This review describes the primary properties of CaN and illustrates its functions and modes of action by focusing on several representative targets, in particular glutamate receptors, striatal enriched protein phosphatase (STEP), and neuromodulin (GAP43), and their functional significance for synaptic plasticity and memory. 相似文献
316.
Adolescence is characterized by major developmental changes that may render the individual vulnerable to stress and the development of psychopathologies in a sex-specific manner. Earlier we reported lower anxiety-like behavior and higher risk-taking and novelty seeking in rats previously exposed to peri-pubertal stress. Here we studied whether peri-pubertal stress affected the acquisition and extinction of fear memories and/or the associated functional engagement of various brain regions, as assessed with 2-deoxyglucose. We showed that while peri-pubertal stress reduced freezing during the acquisition of fear memories (training) in both sexes, it had a sex-specific effect on extinction of these memories. Moreover hippocampus, basal amygdala and cingulate and motor cortices showed higher metabolic rates during extinction in rats exposed to peri-pubertal stress. Interestingly, activation of the infralimbic cortex was negatively correlated with freezing during extinction only in control males, while only males stressed during puberty showed a significant correlation between behavior during extinction and metabolic activation of hippocampus, amygdala and paraventricular nucleus. No correlations between brain activation and behavior during extinction were observed in females (control or stress). These results indicate that exposure to peri-pubertal stress affects behavior and brain metabolism when the individual is exposed to an additional stressful challenge. Some of these effects are sex-specific. 相似文献
317.
We propose 2 related models for the meta-analysis of diagnostic tests. Both models are based on the bivariate normal distribution for transformed sensitivities and false-positive rates. Instead of using the logit as a transformation for these proportions, we employ the tα family of transformations that contains the log, logit, and (approximately) the complementary log. A likelihood ratio test for the cutoff value problem is developed, and summary receiver operating characteristic (SROC) curves are discussed. Worked examples showcase the methodology. We compare the models to the hierarchical SROC model, which in contrast employs a logit transformation. Data from various meta-analyses are reanalyzed, and the reanalysis indicates a better performance of the models based on the tα transformation. (PsycINFO Database Record (c) 2012 APA, all rights reserved). 相似文献
318.
Prior research has found that perceived discrimination is associated with adverse mental health outcomes among Latinos. However, the process by which this relationship occurs remains an understudied area. The present study investigated the role of acculturative stress in underlying the relationship between perceived discrimination and Latino psychological distress. Also examined was the ability of acculturation to serve as a moderator between perceived discrimination and acculturative stress. Among a sample of Latino adults (N = 669), moderated mediational analyses revealed that acculturative stress mediated the perceived discrimination-psychological distress relationship, and that the link between perceived discrimination and acculturative stress was moderated by Anglo behavioral orientation but not Latino behavioral orientation. The findings are discussed within a stress and coping perspective that identifies the psychological consequences associated with perceived discrimination and acculturative stress. 相似文献
319.
The current study sets out to explore test anxiety in adolescent students. The effect of sociodemographic variables on test anxiety was controlled for and the relationship between test anxiety and other psychological constructs, such as self-criticism, social anxiety, acceptance and mindfulness, was examined. In addition, the predictive effect/power of these variables was analyzed and a comparative study between high and low test anxiety adolescents was conducted. Participants in this study were 449 high school students, 211 boys and 238 girls, with a mean age of 16.28 years. These participants completed a battery of self-report questionnaires composed by the Portuguese versions of Test Anxiety Inventory (TAI), Child Acceptance and Mindfulness Measure (CAMM), Forms of Self-Criticizing/Attacking and Self-Reassuring Scale (FSCRS), and the Social Anxiety and Avoidance Scale for Adolescents (SAASA). Results showed that gender, self-criticism and competencies for acceptance and mindfulness had a significant and an independent contribution on the prediction of test anxiety. The comparative study revealed that adolescents with high test anxiety score significantly higher in negative forms of self-criticism, social anxiety and lower in self-reassurance, acceptance and mindfulness, when compared to those with low test anxiety. Despite its exploratory nature, the current study adds to the existing knowledge on the influence of psychological processes, such as self-criticism and acceptance, on test anxiety. These findings might constitute a relevant contribution to psychological intervention with adolescents. 相似文献
320.
Losada A de los Angeles Villareal M Nuevo R Márquez-González M Salazar BC Romero-Moreno R Carrillo AL Fernáñdez-Fernández V 《The Spanish journal of psychology》2012,15(2):783-792
The Center for Epidemiologic Studies-Depression Scale (CES-D) is the most frequently used scale for measuring depressive symptomatology in caregiving research. The aim of this study is to test its construct structure and measurement equivalence between caregivers from two Spanish-speaking countries. Face-to-face interviews were carried out with 595 female dementia caregivers from Madrid, Spain, and from Coahuila, Mexico. The structure of the CES-D was analyzed using exploratory and confirmatory factor analysis (EFA and CFA, respectively). Measurement invariance across samples was analyzed comparing a baseline model with a more restrictive model. Significant differences between means were found for 7 items. The results of the EFA clearly supported a four-factor solution. The CFA for the whole sample with the four factors revealed high and statistically significant loading coefficients for all items (except item number 4). When equality constraints were imposed to test for the invariance between countries, the change in chi-square was significant, indicating that complete invariance could not be assumed. Significant between-countries differences were found for three of the four latent factor mean scores. Although the results provide general support for the original four-factor structure, caution should be exercised on reporting comparisons of depression scores between Spanish-speaking countries. 相似文献