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151.
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   
152.
The purpose of the present study was to analyse the psychometric properties of the 'Questionnaire of Sociocultural Influences on the Aesthetic Body Shape Model' (CIMEC-26) in a Spanish adolescent population. This questionnaire measures the influence of agents and situations that transmit the current aesthetic model, and assesses environmental influences favouring thinness. The CIMEC-26 was administered to a sample of 4031 female primary and secondary school students ranging in age from 10 to 17 years (M?=?14, SD?=?1.34). Results suggested that the CIMEC-26 has acceptable internal consistency (α?=?.93). The oldest group (15-17 years) had the highest scores on all factors and the highest total scores, suggesting greater influence of the aesthetic body shape model and higher vulnerability to social pressure to achieve it. Factor analysis suggested three moderately interrelated components of the scale. Confirmatory factor analysis showed that both the three-factor solution and the original five-factor structure had good fit indices, although the latter showed the best fit. The CIMEC-26 proved to be an effective instrument for research on the social influence on the aesthetic body model in female adolescents.  相似文献   
153.
This study broaches in a novel way the analysis of cognitive impairment characteristic of the early stages of Alzheimer's Disease (AD). Specifically, we attempt to determine the acoustic speech parameters that are sensitive to the onset of the disease, and their association with the language deficit characteristic of AD. Speech analysis was carried out on 21 elderly patients with AD using Praat software, which analyzes the acoustic components of speech. The data obtained were subjected to stepwise regression, using the overall scores obtained in the test as the criterion variable, and the scores on the frequency, amplitude and periodicity variables as predictors of performance. We found that the percentage of voiceless segments explains a significant portion of the variance in the overall scores obtained in the neuropsychological test. This component seems to be related mainly to the patient's ability in phonological fluency. This finding could permit the creation of a diagnostic test for AD through analysis of the acoustic speech parameters at very low cost in terms of both time and resources.  相似文献   
154.
The purpose of this study was to investigate the moderating effect of having vs. not having a and quality of life. In-person interviews were conducted with 55 male and 64 female inmates from the Topas Penitentiary (Spain). Higher levels of social loneliness and lower levels of sexual satisfaction were associated with lower levels of quality of life. In addition, the interaction between sexual satisfaction and romantic partner status was significant. Higher levels of sexual satisfaction were associated with higher levels of quality of life only for the group without a partner. These findings support a "bad is stronger than good" principle and indicate the detrimental aspects that can be associated with not having a satisfactory sexual life while incarcerated.  相似文献   
155.
As a result of studies examining factors involved in the learning process, various structural models have been developed to explain the direct and indirect effects that occur between the variables in these models. The objective was to evaluate a structural model of cognitive and motivational variables predicting academic achievement, including general intelligence, academic self-concept, goal orientations, effort and learning strategies. The sample comprised of 341 Spanish students in the first year of compulsory secondary education. Different tests and questionnaires were used to evaluate each variable, and Structural Equation Modelling (SEM) was applied to contrast the relationships of the initial model. The model proposed had a satisfactory fit, and all the hypothesised relationships were significant. General intelligence was the variable most able to explain academic achievement. Also important was the direct influence of academic self-concept on achievement, goal orientations and effort, as well as the mediating ability of effort and learning strategies between academic goals and final achievement.  相似文献   
156.
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   
157.
The Memory Failures of Everyday Questionnaire (MFE) is one of the most widely-used instruments to assess memory failures in daily life. The original scale has nine response options, making it difficult to apply; we created a three-point scale (0-1-2) with response choices that make it easier to administer. We examined the two versions' equivalence in a sample of 193 participants between 19 and 64 years of age. The test-retest reliability and internal consistency of the version we propose were also computed in a sample of 113 people. Several indicators attest to the two forms' equivalence: the correlation between the items' means (r = .94; p < .001) and the order of the items' frequencies (r = .92; p < .001). However, the correlation between global scores on the two forms was not very high (r = .67; p < .001). The results indicate this new version has adequate reliability and internal consistency (r(xx) = .83; p < .001; alpha = .83; p < .001) equivalent to those of the MFE 1-9. The MFE 0-2 provides a brief, simple evaluation, so we recommend it for use in clinical practice as well as research.  相似文献   
158.
In the last five decades, cognitive scientists and the psychologists of reasoning have dedicated a lot of effort designing usable traffic signs. This study investigated the interference effect produced by the position of the sign elements in traffic signage on response accuracy and reaction time. Sixteen drivers performed a flanker interference reaction time task. Incongruent graphical/space solutions, actually used for the airport stack-type sign, lead to increased reaction time and a reduction in the proportion of correct answers. These results suggest that incongruent visual information should be avoided, as this might impair drivers’ performance. These findings provide important information for the specification of future signage design guidelines and for improving road safety.  相似文献   
159.
The aim of the present investigation was to study the visual communication between humans and dogs in relatively complex situations. In the present research, we have modelled more lifelike situations in contrast to previous studies which often relied on using only two potential hiding locations and direct association between the communicative signal and the signalled object. In Study 1, we have provided the dogs with four potential hiding locations, two on each side of the experimenter to see whether dogs are able to choose the correct location based on the pointing gesture. In Study 2, dogs had to rely on a sequence of pointing gestures displayed by two different experimenters. We have investigated whether dogs are able to recognise an ‘indirect signal’, that is, a pointing toward a pointer. In Study 3, we have examined whether dogs can understand indirect information about a hidden object and direct the owner to the particular location. Study 1 has revealed that dogs are unlikely to rely on extrapolating precise linear vectors along the pointing arm when relying on human pointing gestures. Instead, they rely on a simple rule of following the side of the human gesturing. If there were more targets on the same side of the human, they showed a preference for the targets closer to the human. Study 2 has shown that dogs are able to rely on indirect pointing gestures but the individual performances suggest that this skill may be restricted to a certain level of complexity. In Study 3, we have found that dogs are able to localise the hidden object by utilising indirect human signals, and they are able to convey this information to their owner.  相似文献   
160.
Recent dog-infant comparisons have indicated that the experimenter's communicative signals in object hide-and-search tasks increase the probability of perseverative (A-not-B) errors in both species (Topál et al. 2009). These behaviourally similar results, however, might reflect different mechanisms in dogs and in children. Similar errors may occur if the motor response of retrieving the object during the A trials cannot be inhibited in the B trials or if the experimenter's movements and signals toward the A hiding place in the B trials ('sham-baiting') distract the dogs' attention. In order to test these hypotheses, we tested dogs similarly to Topál et al. (2009) but eliminated the motor search in the A trials and 'sham-baiting' in the B trials. We found that neither an inability to inhibit previously rewarded motor response nor insufficiencies in their working memory and/or attention skills can explain dogs' erroneous choices. Further, we replicated the finding that dogs have a strong tendency to commit the A-not-B error after ostensive-communicative hiding and demonstrated the crucial effect of socio-communicative cues as the A-not-B error diminishes when location B is ostensively enhanced. These findings further support the hypothesis that the dogs' A-not-B error may reflect a special sensitivity to human communicative cues. Such object-hiding and search tasks provide a typical case for how susceptibility to human social signals could (mis)lead domestic dogs.  相似文献   
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