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141.
Faculty members at Canadian business schools were surveyed regarding their ethical perceptions of behaviours related to undergraduate instruction. Fifty-five behavioural statements were listed and respondents were asked to rate the extent to which they felt each behaviour was ethical or unethical. The only item that respondents endorsed as unequivocally unethical (90% indicated it was definitely unethical) was Becoming sexually involved with an undergraduate in one of your classes. We also compared the results of our sample to those of an American sample. Overall, an interesting pattern of differences emerged between the responses obtained in Canada and the U.S. In general, the direction of the significant differences was such that Canadian professors viewed the behaviours in question as less ethical than did their American counterparts.  相似文献   
142.
Previous research on schizophrenia suggests that context-processing disturbances are one of the core cognitive deficits present in schizophia. However, it is not clear whether such deficits are specific to schizophrenia as compared with other psychotic disorders. To address this question, the authors administered a version of the AX Continuous Performance Test designed to assess context processing in a sample of healthy controls, patients with schizophrenia, and patients with other psychotic disorders. Participants were tested at index (when medication naive and experiencing their first contact with psychiatric services) and 4 weeks later, following medication treatment. At index, patients with schizophrenia and the psychotic comparison group demonstrated similar impairments in context processing. However, context-processing deficits improved in the psychotic comparison group at 4 weeks but did not improve in patients with schizophrenia.  相似文献   
143.
Three experiments are reported in which observers judged the three-dimensional (3-D) structures of virtual or real objects defined by various combinations of texture, motion, and binocular disparity under a wide variety of conditions. The tasks employed in these studies involved adjusting the depth of an object to match its width, adjusting the planes of a dihedral angle so that they appeared orthogonal, and adjusting the shape of an object so that it appeared to match another at a different viewing distance. The results obtained on all of these tasks revealed large constant errors and large individual differences among observers. There were also systematic failures of constancy over changes in viewing distance, orientation, or response task. When considered in conjunction with other, similar reports in the literature, these findings provide strong evidence that human observers do not have accurate perceptions of 3-D metric structure.  相似文献   
144.
Biased category payoff matrices engender separate reward- and accuracy-maximizing decision criteria Although instructed to maximize reward, observers use suboptimal decision criteria that place greater emphasis on accuracy than is optimal. In this study, objective classifier feedback (the objectively correct response) was compared with optimal classifier feedback (the optimal classifier's response) at two levels of category discriminability when zero or negative costs accompanied incorrect responses for two payoff matrix multiplication factors. Performance was superior for optimal classifier feedback relative to objective classifier feedback for both zero- and negative-cost conditions, especially when category discriminability was low, but the magnitude of the optimal classifier advantage was approximately equal for zero- and negative-cost conditions. The optimal classifier feedback performance advantage did not interact with the payoff matrix multiplication factor. Model-based analyses suggested that the weight placed on accuracy was reduced for optimal classifier feedback relative to objective classifier feedback and for high category discriminability relative to low category discriminability. In addition, the weight placed on accuracy declined with training when feedback was based on the optimal classifier and remained relatively stable when feedback was based on the objective classifier. These results suggest that feedback based on the optimal classifier leads to superior decision criterion learning across a wide range of experimental conditions.  相似文献   
145.
It has been reported that it is harder to switch to a strong, well-practiced task from a weaker, less-practiced task than vice versa. Three experiments replicated this surprising asymmetry and investigated how it is affected by a reduction in interference between tasks. Experiment 1 progressively delayed the onset of the stimulus attribute associated with the stronger task. Experiments 2 and 3 separated the response sets of the tasks. Both manipulations reduced, without eliminating, interference of the stronger with the weaker task but reversed the asymmetry of switch costs, resulting in a larger cost of switching to the weaker task. The results are interpreted in terms of a model of the interactions between control input, task strength, and task priming.  相似文献   
146.
Although a number of studies have explored the ways that men and women romantically attract mates, almost no research exists on the special tactics people use when already in a relationship and trying to attract someone new--a process known as mate poaching enticement. In Study 1, the authors investigated the tactics people use to entice others into making mate poaching attempts. Enticement tactic effectiveness conformed to evolutionary-predicted patterns across sex and temporal context. In Study 2, the authors examined the tactics men and women use to disguise mate poaching enticement. The most effective camouflage for poaching also varied between sex in evolutionary-predicted ways, regardless of the target of deception (i.e., current partner vs. larger community). Discussion focuses on limitations of this research, future investigative directions, unexpected findings, and the utility of placing mate poaching attraction within the broader context of human sexual strategies.  相似文献   
147.
The Category Test (CT) is a neuropsychological measure that taps into multiple domains of complex reasoning but yields a single error score, limiting the use of the test. In this study, three new CT scales were developed to assess specific aspects of executive dysfunction: Perseveration, Failure to Maintain Cognitive Set, and Inability to Recall and Re-Initiate Past Behavior. The relationship of these scales to well-established neuropsychological measures was examined in head-injured individuals and schizophrenia patients. The CT Perseveration score was correlated with the Wisconsin Card Sorting Test (WCST) Perseverative Responses score, but also with measures from the Wechsler Memory Scale-Revised and the California Verbal Learning Test. The CT Memory score correlated with other memory measures, but also with the WCST Perseveration measure. Although future studies designed to test discriminant and convergent validity are warranted, these scales may be useful in determining specific aspects of impaired CT performance.  相似文献   
148.
Neuroimaging and computational modeling studies have led to the suggestion that response conflict monitoring by the anterior cingulate cortex plays a key role in cognitive control. For example, response conflict is high when a response must be withheld (no-go) in contexts in which there is a prepotent tendency to make an overt (go) response. An event-related brain potential (ERP) component, the N2, is more pronounced on no-go than on go trials and was previously thought to reflect the need to inhibit the go response. However, the N2 may instead reflect the high degree of response conflict on no-go trials. If so, an N2 should also be apparent when subjects make a go response in conditions in which nogo events are more common. To test this hypothesis, we collected high-density ERP data from subjects performing a go/no-go task, in which the relative frequency of go versus no-go stimuli was varied. Consistent with our hypothesis, an N2 was apparent on both go and no-go trials and showed the properties expected of an ERP measure of conflict detection on correct trials: (1) It was enhanced for low-frequency stimuli, irrespective of whether these stimuli were associated with generating or suppressing a response, and (2) it was localized to the anterior cingulate cortex. This suggests that previous conceptions of the no-go N2 as indexing response inhibition may be in need of revision. Instead, the results are consistent with the view that the N2 in go/no-go tasks reflects conflict arising from competition between the execution and the inhibition of a single response.  相似文献   
149.
In modern digital applications, users often interact with virtual representations of themselves or others, called avatars. We examined how these avatars and their perspectives influence stimulus–response compatibility in a Simon task. Participants responded to light/dark blue stimuli with left/right key presses in the presence of a task-irrelevant avatar. Changes in stimulus–response compatibility were used to quantify changes in the mental representation of the task and perspective taking toward this avatar. Experiments 1 and 2 showed that perspective taking for an avatar occurred in orthogonal stimulus–response mappings, causing a compatibility effect from the avatar’s point of view. In the following two experiments we introduced a larger variety of angular disparities between the participant and avatar. In Experiment 3, the Simon effect with lateralized stimulus positions remained largely unaffected by the avatar, pointing toward an absence of perspective taking. In Experiment 4, after avatar hand movements were added in order to strengthen the participants’ sense of agency over the avatar, a spatial compatibility effect from the avatar’s perspective was observed again, and hints of the selective use of perspective taking on a trial-by-trial basis were found. Overall, the results indicate that users can incorporate the perspective of an avatar into their mental representation of a situation, even when this perspective is unnecessary to complete a task, but that certain contextual requirements have to be met.  相似文献   
150.
This paper reviews the current status of research on the phenomenology, etiology, maintenance, assessment, and treatment of childhood and adolescent social anxiety disorder (SAD). Despite being one of the most prevalent disorders of childhood and adolescence, SAD paradoxically stands as one of the least recognized, researched, and treated pediatric disorders. The small treatment outcome literature provides preliminary support to the effectiveness of various forms of cognitive behavior therapy. The majority of studies to date, however, are limited by inadequate control conditions. Other findings include some support for the utility of parental involvement in treatment, significant advancements in outcome measures (e.g., normative comparisons, indices of naturalistic social functioning), and impressive durability of gains for the majority of treatments. Future directions are suggested, including experimental and naturalistic studies of developmental pathways and maintenance factors, the incorporation of positive psychology constructs (e.g., positive emotions, hope, self-control) in treatment and prevention, and the continued delineation of differences between child, adolescent, and adult manifestations of SAD.  相似文献   
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