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991.
It is widely recognized that abdominal pain and discomfort are common problems in the United States and are often associated with negative quality of life. The prevalence of anxiety/depression elevations and disorders among persons with gastrointestinal disturbances (GI) is estimated to be at least two to three times the rate in the general population. Visceral sensitivity reflects anxiety about GI sensations and its accompanying contexts and often leads to worsening of sensations (e.g. bloating, upset stomach, diarrhea). Among individuals with GI symptoms, visceral sensitivity may be associated with interpreting common sensations as catastrophic which may be related to greater difficulties with emotion dysregulation (e.g. severe anxiety and depression). The current study evaluated the indirect association of visceral sensitivity via emotion dysregulation in relation to depression, anxious arousal, and social anxiety symptoms among 344 young adults with a current history of GI symptoms and problems. Results indicated an indirect effect of visceral sensitivity via emotion dysregulation. These findings provide novel empirical support for the association of visceral sensitivity with emotional distress symptoms among young adults with GI symptoms. Based on the results, targeting emotion dysregulation may be a promising health promotion tactic among young adults with GI symptoms and disorders.  相似文献   
992.
The development of cognitive models involves the creative scientific formalization of assumptions, based on theory, observation, and other relevant information. In the Bayesian approach to implementing, testing, and using cognitive models, assumptions can influence both the likelihood function of the model, usually corresponding to assumptions about psychological processes, and the prior distribution over model parameters, usually corresponding to assumptions about the psychological variables that influence those processes. The specification of the prior is unique to the Bayesian context, but often raises concerns that lead to the use of vague or non-informative priors in cognitive modeling. Sometimes the concerns stem from philosophical objections, but more often practical difficulties with how priors should be determined are the stumbling block. We survey several sources of information that can help to specify priors for cognitive models, discuss some of the methods by which this information can be formalized in a prior distribution, and identify a number of benefits of including informative priors in cognitive modeling. Our discussion is based on three illustrative cognitive models, involving memory retention, categorization, and decision making.  相似文献   
993.
Yoga contains sub-components related to its physical postures (asana), breathing methods (pranayama), and meditation (dhyana). To test the hypothesis that specific yoga practices are associated with reduced psychological distress, 186 adults completed questionnaires assessing life stressors, symptom severity, and experience with each of these aspects of yoga. Each yoga sub-component was found to be negatively correlated with psychological distress indices. However, differing patterns of relationship to psychological distress symptoms were found for each yoga sub-component. Experience with asana was negatively correlated with global psychological distress (r = ?.21, p < .01), and symptoms of anxiety (r = ?.18, p = .01) and depression (r = ?.17, p = .02). These relationships remained statistically significant after accounting for variance attributable to Social Readjustment Rating Scale scores (GSI: r = ?.19, p = .01; BSI Anxiety: r = ?.16, p = .04; BSI Depression: r = ?.14, p = .05). By contrast, the correlations between other yoga sub-components and symptom subscales became non-significant after accounting for exposure to life stressors. Moreover, stressful life events moderated the predictive relationship between amount of asana experience and depressive symptoms. Asana was not related to depressive symptoms at low levels of life stressors, but became associated at mean (t[182] = ?2.73, p < .01) and high levels (t[182] = ?3.56, p < .001). Findings suggest asana may possess depressive symptom reduction benefits, particularly as life stressors increase. Additional research is needed to differentiate whether asana has an effect on psychological distress, and to better understand potential psychophysiological mechanisms of action.  相似文献   
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996.
The purpose of the present study was to examine whether rhesus monkeys remember information about their own agency—along with spatial, temporal and contextual properties—from a previously experienced event. In Experiment 1, rhesus monkeys (n = 4) used symbols to reliably indicate whether they had performed or observed an event on a computer screen. In Experiment 2, naïve and experienced monkeys (n = 8) reported agency information when stringent controls for perceptual and proprioceptive cues were included. In Experiment 3, five of the monkeys completed a task in which they reported agency information along with spatial and temporal features of events. Two monkeys performed this agency discrimination when they could not anticipate which memory test they would receive. There was also evidence that these features were integrated in memory. Implications of this research are discussed in relation to working memory, episodic memory and self-awareness in nonhuman animals.  相似文献   
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Examining how animals direct social learning during skill acquisition under natural conditions, generates data for examining hypotheses regarding how transmission biases influence cultural change in animal populations. We studied a population of macaques on Koram Island, Thailand, and examined model-based biases during interactions by unskilled individuals with tool-using group members. We first compared the prevalence of interactions (watching, obtaining food, object exploration) and proximity to tool users during interactions, in developing individuals (infants, juveniles) versus mature non-learners (adolescents, adults), to provide evidence that developing individuals are actively seeking information about tool use from social partners. All infants and juveniles, but only 49% of mature individuals carried out interacted with tool users. Macaques predominantly obtained food by scrounging or stealing, suggesting maximizing scrounging opportunities motivates interactions with tool users. However, while interactions by adults was limited to obtaining food, young macaques and particularly infants also watched tool users and explored objects, indicating additional interest in tool use itself. We then ran matrix correlations to identify interaction biases, and what attributes of tool users influenced these. Biases correlated with social affiliation, but macaques also preferentially targeted tool users that potentially increase scrounging and learning opportunities. Results suggest that social structure may constrain social learning, but the motivation to bias interactions towards tool users to maximize feeding opportunities may also socially modulate learning by facilitating close proximity to better tool users, and further interest in tool-use actions and materials, especially during development.  相似文献   
999.
1000.
Psychopathy is a personality disorder accompanied by abnormalities in emotional processing and attention. Recent theoretical applications of network-based models of cognition have been used to explain the diverse range of abnormalities apparent in psychopathy. Still, the physiological basis for these abnormalities is not well understood. A significant body of work has examined psychopathy-related abnormalities in simple attention-based tasks, but these studies have largely been performed using electrocortical measures, such as event-related potentials (ERPs), and they often have been carried out among individuals with low levels of psychopathic traits. In this study, we examined neural activity during an auditory oddball task using functional magnetic resonance imaging (fMRI) during a simple auditory target detection (oddball) task among 168 incarcerated adult males, with psychopathic traits assessed via the Hare Psychopathy Checklist-Revised (PCL-R). Event-related contrasts demonstrated that the largest psychopathy-related effects were apparent between the frequent standard stimulus condition and a task-off, implicit baseline. Negative correlations with interpersonal-affective dimensions (Factor 1) of the PCL-R were apparent in regions comprising default mode and salience networks. These findings support models of psychopathy describing impaired integration across functional networks. They additionally corroborate reports which have implicated failures of efficient transition between default mode and task-positive networks. Finally, they demonstrate a neurophysiological basis for abnormal mobilization of attention and reduced engagement with stimuli that have little motivational significance among those with high psychopathic traits.  相似文献   
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