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901.
Little is known about whether severe psychopathology influences the assessment of self-reported attachment style. Fifty-eight randomly selected adult psychiatric inpatients completed the Experiences in Close Relationship questionnaire (ECR; Brennan, Clark, & Shaver, 1998) and were administered the 24-item Brief Psychiatric Rating Scale (BPRS; Ventura et al., 1993) and the Hamilton Depression Rating Scale (HDRS; Hamilton, 1960) at both admission and discharge. The Structured Clinical Interview for DSM-IV (SCID-I; First, Spitzer, Gibbon, & Williams, 1996) was used to establish Axis I diagnoses. The ECR scales showed good internal consistency and absolute stability both in patients with (n = 24) and without (n = 34) a psychotic disorder. Relative stability was only fair among patients with psychotic disorders but good among patients without psychotic disorders. Neither higher BPRS or HDRS scores, nor the presence of a psychotic disorder, significantly reduced the retest reliability of the ECR scales. These findings suggest that self-report measures might provide a reliable assessment of attachment style in patients with severe psychopathology, except for the most severely impaired patients.  相似文献   
902.
In the presence of several objectives, goal conflict may be avoided via multifinal means, which advance all of the active goals at once. Because such means observe multiple constraints, they are fewer in number than the unconstrained means to a single goal. Five experimental studies investigated the process of choosing or generating such means for multiple goals. We found that the simultaneous activation of multiple goals restricted the set of acceptable means to ones that benefitted (or at least, did not harm) the entire set of active goals. Two moderators of this phenomenon were identified: (a) the feasibility of identifying multifinal means, which was dependent on the relations between the different active goals, and (b) the enhanced importance of the focal goal, which resulted in the inhibition of its alternatives and the consequent relaxation of multifinality constraints.  相似文献   
903.
Research on bystander intervention has produced a great number of studies showing that the presence of other people in a critical situation reduces the likelihood that an individual will help. As the last systematic review of bystander research was published in 1981 and was not a quantitative meta-analysis in the modern sense, the present meta-analysis updates the knowledge about the bystander effect and its potential moderators. The present work (a) integrates the bystander literature from the 1960s to 2010, (b) provides statistical tests of potential moderators, and (c) presents new theoretical and empirical perspectives on the novel finding of non-negative bystander effects in certain dangerous emergencies as well as situations where bystanders are a source of physical support for the potentially intervening individual. In a fixed effects model, data from over 7,700 participants and 105 independent effect sizes revealed an overall effect size of g = -0.35. The bystander effect was attenuated when situations were perceived as dangerous (compared with non-dangerous), perpetrators were present (compared with non-present), and the costs of intervention were physical (compared with non-physical). This pattern of findings is consistent with the arousal-cost-reward model, which proposes that dangerous emergencies are recognized faster and more clearly as real emergencies, thereby inducing higher levels of arousal and hence more helping. We also identified situations where bystanders provide welcome physical support for the potentially intervening individual and thus reduce the bystander effect, such as when the bystanders were exclusively male, when they were naive rather than passive confederates or only virtually present persons, and when the bystanders were not strangers.  相似文献   
904.
Individuals of all ages extract structure from the sequences of patterns they encounter in their environment, an ability that is at the very heart of cognition. Exactly what underlies this ability has been the subject of much debate over the years. A novel mechanism, implicit chunk recognition (ICR), is proposed for sequence segmentation and chunk extraction. The mechanism relies on the recognition of previously encountered subsequences (chunks) in the input rather than on the prediction of upcoming items in the input sequence. A connectionist autoassociator model of ICR, truncated recursive autoassociative chunk extractor (TRACX), is presented in which chunks are extracted by means of truncated recursion. The performance and robustness of the model is demonstrated in a series of 9 simulations of empirical data, covering a wide range of phenomena from the infant statistical learning and adult implicit learning literatures, as well as 2 simulations demonstrating the model's ability to generalize to new input and to develop internal representations whose structure reflects that of the items in the input sequence. TRACX outperforms PARSER (Perruchet & Vintner, 1998) and the simple recurrent network (SRN, Cleeremans & McClelland, 1991) in matching human sequence segmentation on existing data. A new study is presented exploring 8-month-olds' use of backward transitional probabilities to segment auditory sequences.  相似文献   
905.
Wu K  Li C  Johnson DE 《Psychological reports》2011,108(1):239-251
The relations among self-esteem, stress, and ingratiatory behaviors in the workplace were examined. Competing models for moderating and mediating effects of self-esteem on the relationship between stress and ingratiation were presented. Data from a sample of 136 employees at a state lottery organization were used to test the competing models. Support was found for the full mediation model, wherein self-esteem completely mediated the relationship between stress and ingratiation.  相似文献   
906.
Posttraumatic stress disorder (PTSD) is an anxiety disorder in which an individual re-experiences a traumatic event, avoids situations related to it, and shows excessive arousal. The disorder appears after experiencing a life-threatening event, such as a war or a natural disaster. Thus, the validation of tests which assess the disorder after the earthquake on February 27, 2010, in Chile is crucial for its evaluation and subsequent intervention. The present study includes psychometric data for the Posttraumatic Stress Disorder Checklist-Civilian version (PCL-C) on a sample of 509 survivors of the disaster. Values indicate good psychometric properties of the questionnaire.  相似文献   
907.
When people's health is threatened, they generally develop illness perceptions to make sense of their illness. The Illness Perception Questionnaire (IPQ-R), developed by Moss-Morris et al (2002), has been widely used in many countries to measure such representations. However, since studies in this crucial research area are lacking in Sweden a Swedish version of IPQ-R was validated with a focus on the seven subscales: timeline acute/chronic, timeline cyclical, consequences, personal control, treatment control, illness coherence and emotional representations. Using confirmatory factor analysis, the aim of the present study was to validate the internal structure of the Swedish version in a sample of 202 persons (144 men and 58 women) who had been diagnosed with myocardial infarction four months earlier. Additionally, inter-correlations among the seven subscales and external concurrent validity were also investigated. The results of confirmatory factor analysis revealed that, in line with the English version of the IPQ-R, the specified seven-factor model had a satisfactory fit. One item was however not considered reliable and was therefore excluded from the instrument. The internal consistency (Cronbach's alpha coefficients) and the inter-factor correlations were relatively similar to those reported in the validation study of the original English IPQ-R. In tests of concurrent validity, the seven IPQ-R subscales were, as hypothesized, mainly associated with external variables. To conclude, the Swedish version of the IPQ-R's seven dimensions, with one item removed, (total 37 items) was found to be a reliable and valid measure of illness perception.  相似文献   
908.
Individuals display high levels of trust and express feelings of safety when interacting with social ingroup members. Here, we investigated whether cues related to ingroup membership would change perceptions of the safety of alcohol. Participants were exposed to images of beer in either a standard can or a can featuring the colors of their university (i.e., ‘fan cans’). We hypothesized that exposure to fan cans would change perceptions of the risks of beer drinking. Results showed that participants exposed to fan cans rated beer consumption as less dangerous (Experiment 1), were more likely to automatically activate safety-related mental content after unconscious perception of beer cues (Experiment 2), and viewed their ingroup's party practices as less dangerous (Experiment 3). These results provide evidence that ingroup-associated colors can serve as a safety cue for alcohol, which may in theory perpetuate alcohol-related risk-taking, already a cause for concern on college and university campuses.  相似文献   
909.
Twelve rats made repeated choices on an adjusting-delay schedule between a smaller reinforcer (A) that was delivered immediately after a response and a larger reinforcer (B) that was delivered after a delay which increased or decreased by 20% depending on the subject's choices in successive blocks of trials. In two phases of the experiment (100 sessions and 40 sessions), reinforcer sizes were selected which enabled theoretical parameters expressing the rate of delay discounting and sensitivity to reinforcer size to be estimated from the ratio of the indifference delays obtained in the two phases. Indifference delays, calculated from adjusting delays in the last 10 sessions of each phase, were shorter when the sizes of A and B were 14 and 25 μl of a 0.6 M sucrose solution than when they were 25 and 100 μl of the same solution. The ratio of the indifference delays was significantly smaller than that predicted on the basis of an assumed linear relation between reinforcer size and instantaneous reinforcer value, consistent with a previous proposal that this relation may be hyperbolic in form. Estimates of the rate of delay discounting based on the ratio of the two indifference delays (mean, 0.08 s(-1)) were similar to values obtained previously using different intertemporal choice protocols. Estimates of the size-sensitivity parameter (mean 113 μl) were similar to estimates recently derived from performance on progressive-ratio schedules. In both phases of the experiment, adjusting delays in successive blocks of trials were analyzed using the Fourier transform. The power spectrum obtained from individual rats had a dominant frequency that corresponded to a period of oscillation of the adjusting delay between 30 and 100 trial blocks (mean, 78). Power in the dominant frequency band was highest in the early sessions of the first phase and declined with extended training. It is suggested that this experimental protocol may have utility in neurobehavioral studies of intertemporal choice.  相似文献   
910.
Saccadic endpoint variability is often viewed as the outcome of neural noise occurring during sensorimotor processing. However, part of this variability might result from operant learning. We tested this hypothesis by reinforcing dispersions of saccadic amplitude distributions, while maintaining constant their medians. In a first experiment we reinforced the least frequent saccadic amplitudes to increase variability, and then reinforced the central part of the amplitude distributions to reduce variability. The target was placed at a constant distance from the fovea after the saccade to maintain the postsaccadic visual signal constant and an auditory reinforcement was delivered depending on saccadic amplitude. The second experiment tested the effects of the contingency. We reinforced high levels of variability in 4 participants, whereas 4 other participants were assigned to a yoked control group. On average, saccadic amplitude standard deviations were doubled while the medians remained mostly unchanged in the experimental participants in both experiments, and variability returned to baseline level when low variability was reinforced. In the control group no consistent changes in amplitude distributions were observed. These results, showing that variability can be reinforced, challenge the idea of a stochastic neural noise. We instead propose that selection processes constrain saccadic amplitude distributions.  相似文献   
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