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221.
In several mammalian and avian species, females show a higher performance than males in tasks requiring cognitive flexibility such as the discrimination reversal learning. A recent study showed that female guppies are twice as efficient as males in a reversal learning task involving yellow–red discrimination, suggesting a higher cognitive flexibility in female guppies. However, the possibility exists that the superior performance exhibited by females does not reflect a general sex difference in cognitive abilities, but instead, is confined to colour discrimination tasks. To address this issue, we compared male and female guppies in two different discrimination reversal learning tasks and we performed a meta-analysis of these experiments and the previous one involving colour discrimination. In the first experiment of this study, guppies were tested in a task requiring them to learn to select the correct arm of a T-maze in order to rejoin a group of conspecifics. In experiment 2, guppies were observed in a numerical task requiring them to discriminate between 5 and 10 dots in order to obtain a food reward. Although females outperformed males in one condition of the T-maze, we did not find any clear evidence of females’ greater reversal learning performance in either experiment. However, the meta-analysis of the three experiments supported the hypothesis of females’ greater reversal learning ability. Our data do not completely exclude the idea that female guppies have a generally higher cognitive flexibility than males; however, they suggest that the size of this sex difference might depend on the task.  相似文献   
222.
The research on imitation in the animal kingdom has more than a century-long history. A specific kind of imitation, auditory–vocal imitation, is well known in birds, especially among songbirds and parrots, but data for mammals are limited to elephants, marine mammals, and humans. Cetaceans are reported to imitate various signals, including species–specific calls, artificial sounds, and even vocalizations from other species if they share the same habitat. Here we describe the changes in the vocal repertoire of a beluga whale that was housed with a group of bottlenose dolphins. Two months after the beluga’s introduction into a new facility, we found that it began to imitate whistles of the dolphins, whereas one type of its own calls seemed to disappear. The case reported here may be considered as an interesting phenomenon of vocal accommodation to new social companions and cross-species socialization in cetaceans.  相似文献   
223.
In the last decade, visual illusions have been repeatedly used as a tool to compare visual perception among species. Several studies have investigated whether non-human primates perceive visual illusions in a human-like fashion, but little attention has been paid to other mammals, and sensitivity to visual illusions has been never investigated in the dog. Here, we studied whether domestic dogs perceive the Delboeuf illusion. In human and non-human primates, this illusion creates a misperception of item size as a function of its surrounding context. To examine this effect in dogs, we adapted the spontaneous preference paradigm recently used with chimpanzees. Subjects were presented with two plates containing food. In control trials, two different amounts of food were presented in two identical plates. In this circumstance, dogs were expected to select the larger amount. In test trials, equal food portion sizes were presented in two plates differing in size: if dogs perceived the illusion as primates do, they were expected to select the amount of food presented in the smaller plate. Dogs significantly discriminated the two alternatives in control trials, whereas their performance did not differ from chance in test trials with the illusory pattern. The fact that dogs do not seem to be susceptible to the Delboeuf illusion suggests a potential discontinuity in the perceptual biases affecting size judgments between primates and dogs.  相似文献   
224.
Background/Objectives: Motivational Enhancement Treatment in Spanish (METS) is a brief intervention aimed at resolving patient ambivalence towards behavior change that has demonstrated efficacy in substance use disorder treatment to reduce use and increase treatment engagement in different populations. In order to have evidence for its implementation in Mexico, a multi-site, randomized, two-arm, controlled clinical trial was conducted at three outpatient addiction treatment centers in the country to compare the effect of METS with Counseling as Usual (CAU). Method: One hundred and twenty patients were randomized to receive three sessions of METS (n = 54) or CAU (n = 66) during the first four weeks of treatment and were assessed during the following 12 weeks. Primary outcome measures were self-reported days of substance use and of treatment services utilization, which were tested using Generalized Estimating Equations. Results: Results associated both conditions with significant changes in substance use over, whereas there were no differences between conditions in substance use or in service utilization. Conclusions: Findings do not support the hypothesis that METS is more effective than CAU, but suggest that brief interventions at treatment initiation may improve patient outcomes.  相似文献   
225.
The longitudinal study aims to expand what is known about the costs and benefits of narrating stressful experiences by exploring changes in rumination within the narrative process and comparing it to changes in self-reflection. Rumination (e.g., brooding, self-criticism, and negative emotions) and self-reflection were measured in stress narratives of 56 college students. There were several goals: (1) examine changes in narrative rumination and narrative self-reflection over 3 days of writing, (2) examine the relations among the changes in narrative rumination variables and narrative self-reflection and (3) examine how changes in narrative rumination and narrative self-reflection relate to multiple measures of psychological functioning. Overall, individuals increased self-reflection over the 3-day writing task. Individuals who increased ruminative brooding across the 3 days of writing showed lower ego identity development (short term and long term) and self-esteem (short term), while increased self-criticism was positively correlated with identity distress (short term). Implications of the different aspects of narrative rumination, specifically in the context of stressful experiences, are discussed.  相似文献   
226.
We investigated academic and behavioral outcomes of internationally adopted children and the associations between these outcomes and age at adoption, time spent in the adoptive family, and parenting. At two time points (T1 and T2, ~15 months apart), we examined early academic skills (school readiness), and parent-reported behavioral adjustment (internalizing and externalizing behavior) and adaptive functioning of a sample of 75 children (45.9% boys, mean age?=?5.17 years) adopted from Russia into US families. We also collected parents’ self-assessments of their parenting at T1. Children who were adopted at a younger age showed higher levels of early academic skills. Correlations between age at adoption and other outcomes were overall small and mostly non-significant. However, adoptees’ academic and behavioral progress differed notably in several respects. Specifically, adoptees improved in early academic skills over time, whereas, as a group, their adaptive functioning and behavioral adjustment remained stable within the normal range. Early academic skills were not related to behavioral adjustment at each time point and over time. The time spent in the adoptive family was positively related to early academic skills at T2. Whereas outcomes showed little to no relation to parenting as reported by mother and father separately, higher discrepancies between mothers' and fathers' reports of positive parenting were related to higher levels of behavioral symptoms and lower levels of adaptive skills at T2. These differential results may be explained in part by drawing upon the notion of dissociated domains of psychological and sociocultural adaptation and acculturation, outlined in the immigration literature. These results also bring to light the possible importance of between-parent consistency in parenting for adoptees’ behavioral outcomes.  相似文献   
227.
This qualitative study investigated the personal and professional stances of 40 health and social care professionals confronted with assisted suicide of older persons living in nursing homes or supported by social welfare or home care and support services in French-speaking Switzerland. Requests of assisted suicide triggered questions with regard to the professional mission, the quality of accompaniment, values, and ethical principles. Four types of stances emerged from the analysis performed according to the principles of the grounded theory: favorable in principle, professional compromise, personal compromise, and opposed in principle. Each stance results from the combination of several dimensions: personal or professional concordance or compatibility with assisted suicide; implication in, and impact of, the process; appreciation of the process; and satisfaction with the resources at disposal. The differentiated stances adopted by professionals depend largely on their way of interpreting their mission, deontology, and the relationship to the older person.  相似文献   
228.
The present study assesses the psychometric properties and factor structure of the Greek version of the Cardiac Anxiety Questionnaire (CAQ). The questionnaire was administered to 598 healthy individuals from 15 different regions of Greece with a measure of socioeconomic characteristics and the Symptom Checklist-90-Revised (SCL-90-R). The sample was split into two random halves, and exploratory factor analysis indicated a three-factor solution. This solution was tested using a confirmatory factor analysis on the second half of the sample. In terms of latent dimensions, the Greek version retains the three-factor structure as proposed by the initial authors. However, adequate fit was achieved only after omitting eight items. The shorter (10-item) version was submitted to further analysis. The shorter version provided satisfactory internal reliability and evidence indicating the validity of the scale with respect to SCL-90-R subscales. The stability of the questionnaire was verified by a high test-retest reliability over a 3-mo. period (r = .86). Sex and age differences were assessed. The 10-item version appears to be a practical, brief tool for clinical use.  相似文献   
229.
Cognitive deficits in fibromyalgia may be specifically related to controlled processes, such as those measured by working memory or executive function tasks. This hypothesis was tested here by measuring controlled temporal preparation (temporal orienting) during a response inhibition (go no-go) task. Temporal orienting effects (faster reaction times for targets appearing at temporally attended vs. unattended moments) and response inhibition were impaired in fibromyalgia compared to the control group. It is concluded that frontal networks underlying attentional control (temporal orienting and response inhibition) can be a dysfunctional neurocognitive mechanism in fibromyalgia.  相似文献   
230.
The present study investigated a possible connection between speech processing and cochlear function. Twenty-two subjects with age range from 18 to 39, balanced for gender with normal hearing and without any known neurological condition, were tested with the dichotic listening (DL) test, in which listeners were asked to identify CV-syllables in a nonforced, and also attention-right, and attention-left condition. Transient evoked otoacoustic emissions (TEOAEs) were recorded for both ears, with and without the presentation of contralateral broadband noise. The main finding was a strong negative correlation between language laterality as measured with the dichotic listening task and of the TEOAE responses. The findings support a hypothesis of shared variance between central and peripheral auditory lateralities, and contribute to the attentional theory of auditory lateralization. The results have implications for the understanding of the cortico-fugal efferent control of cochlear activity.  相似文献   
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