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81.
Sandström A Säll R Peterson J Salami A Larsson A Olsson T Nyberg L 《Stress (Amsterdam, Netherlands)》2012,15(5):503-513
Deficits in executive functioning and working memory associated with frontal lobe dysfunction are prominent in depression and work-related long-term sick leave (LTSL). This study used functional magnetic resonance imaging (fMRI) to investigate potential differences in brain activation patterns in these conditions. In addition, the function of the hypothalamic-pituitary-adrenal (HPA) axis was examined and compared between groups. Since there is a clear overrepresentation of women in these diagnostic groups, and to ensure a more homogenous sample population, only women were included. To examine the neural correlates of relevant cognitive processes in patients on sick leave >90 days due to work-related LTSL, recently diagnosed patients with major depression Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV criteria, untreated), and healthy controls (n?=?10, each group), a 2-back working memory task and a visual long-term memory task were administered during fMRI scanning. HPA axis functioning was investigated using a diurnal curve of saliva cortisol and a dexamethasone suppression test. Task performance was comparable among the three groups. Multivariate image analysis revealed that both memory tasks engaged a similar brain network in all three groups, including the prefrontal and parietal cortex. During the 2-back task, LTSL patients had significant frontal hypoactivation compared to controls and patients with depression. Saliva cortisol measurements showed a flattening of the diurnal rythmicity in LTSL patients compared to patients with depression and healthy contols. Taken together, these findings indicate that work stress-related LTSL and major depression are dissociable in terms of frontal activation and diurnal cortisol rhythmicity. 相似文献
82.
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
83.
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
84.
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
85.
Some children’s social activities are structured by joint goals. In previous research, the criterion used to determine this was relatively weak: if the partner stopped interacting, did the child attempt to re‐engage her? But re‐engagement attempts could easily result from the child simply realizing that she needs the partner to reach her own goal in the activity (social tool explanation). In two experiments, 21‐ and 27‐month‐old children interacted with an adult in games in which they either did or did not physically need the partner to reach a concrete goal. Moreover, when the partner stopped interacting, she did so because she was either unwilling to continue (breaking off from the joint goal) or unable to continue (presumably still maintaining the joint goal). Children of both age groups encouraged the recalcitrant partner equally often whether she was or was not physically needed for goal attainment. In addition, they did so more often when the partner was unable to continue than when she was unwilling to continue. These findings suggest that young children do not just view their collaborative partners as mindless social tools, but rather as intentional, cooperative agents with whom they must coordinate intentional states. 相似文献
86.
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
87.
It is well established that humans and other animals may treat two perceptually different cues alike, if the cues have been
individually paired with a common antecedent or a common consequence. Recently, Molet et al. (Psychon Bull Rev 18:618–623,
2011) reported evidence for a new form of acquired equivalence in human conditional discrimination, namely context-mediated equivalence.
In the present research, using a flavor conditioning procedure, we asked whether rats would show similar context-mediated
equivalence to demonstrate that this new form of acquired equivalence is a general phenomenon. Rats experienced two flavor
cues A and B each presented either in the same context, X, or each in its own distinctive context, X or Y. Subsequently, the
rats experienced B with sucrose in a third context, Z, and then the generalization of conditioning to A was assessed. When
tested in Context Z, consumption of A was more marked when A and B had both been presented in the same context than when they
had been presented in two different contexts. Thus, importantly, in the absence of the training context, cues that shared
a common context at different times came to be treated as equivalent. This represents the first evidence of context-mediated
equivalence in a nonhuman species. 相似文献
88.
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
89.
90.
Thomas Schäfer Arun Tipandjan Peter Sedlmeier 《International journal of psychology》2012,47(5):370-380
Is the use of music in everyday life a culturally universal phenomenon? And do the functions served by music contribute to the development of music preferences regardless of the listener's cultural background? The present study explored similarities and dissimilarities in the functions of music listening and their relationship to music preferences in two countries with different cultural backgrounds: India as an example of a collectivistic society and Germany as an example of an individualistic society. Respondents were asked to what degree their favorite music serves several functions in their life. The functions were summarized in seven main groups: background entertainment, prompt for memories, diversion, emotion regulation, self‐regulation, self‐reflection, and social bonding. Results indicate a strong similarity of the functions of people's favorite music for Indian and German listeners. Among the Indians, all of the seven functions were rated as meaningful; among the Germans, this was the case for all functions except emotion regulation. However, a pronounced dissimilarity was found in the predictive power of the functions of music for the strength of music preference, which was much stronger for Germans than for Indians. In India, the functions of music most predictive for music preference were diversion, self‐reflection, and social bonding. In Germany, the most predictive functions were emotion regulation, diversion, self‐reflection, prompt for memories, and social bonding. It is concluded that potential cultural differences hardly apply to the functional use of music in everyday life, but they do so with respect to the impact of the functions on the development of music preference. The present results are consistent with the assumption that members of a collectivistic society tend to set a higher value on their social and societal integration and their connectedness to each other than do members of individualistic societies. 相似文献