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961.
In the present experiments, we examined whether shifts of attention selectively interfere with the maintenance of both verbal
and spatial information in working memory and whether the interference produced by eye movements is due to the attention shifts
that accompany them. In Experiment 1, subjects performed either a spatial or a verbal working memory task, along with a secondary
task requiring fixation or a secondary task requiring shifts of attention. The results indicated that attention shifts interfered
with spatial, butnot with verbal, working memory, suggesting that the interference is specific to processes within the visuospatial sketchpad.
In Experiment 2, subjects performed a primary spatial working memory task, along with a secondary task requiring fixation,
an eye movement, or an attention shift executed in the absence of an eye movement. The results indicated that both eye movements
and attention shifts interfered with spatial working memory. Eye movements interfered to a much greater extent than shifts
of attention, however, suggesting that eye movements may contribute a unique source of interference, over and above the interference
produced by the attention shifts that accompany them. 相似文献
962.
How rapidly can attention move from one object to the next? Previous studies in which the dwell time paradigm was used have estimated attentional switch times of 200–500 msec, results incompatible with the search rate estimates of 25–50 msec shown in numerous visual search studies. It has been argued that dwell times are so long in the dwell time paradigm because the attentional shifts measured are unlike those used in visual search. In the present experiment, a variation of a visual search task was used, in which serial endogenous (volitional) deployments of attention were measured directly by means of a probe reaction time task. The experiment revealed a dwell time of about 250 msec, consistent with the faster estimates from other dwell time studies. This result suggests that endogenous shifts of attention may be relatively slow and that the faster attentional shifts estimated from visual search tasks may be due to the involvement of bottom-up processes. 相似文献
963.
McNulty, Harkness, Ben-Porath and Williams recently developed Personality Psychopathology Five (PSY-5) scales for the Minnesota Multiphasic Personality Inventory-A (MMPI-A). This study examined these new scales in a sample of 545 adolescents receiving inpatient psychiatric treatment. Item-level principal components analyses were employed to determine the internal structure of each PSY-5 scale and to aid in the creation of facet subscales for each PSY-5 scale. Results suggest that the MMPI-A PSY-5 scales display adequate internal consistency and our findings generally replicate the original work of McNulty et al. but also extend this work by showing that several of the PSY-5 scales may also be subdivided into meaningful lower level dimensions. These facet subscales for each of the MMPI-A PSY-5 scales are offered for further study. 相似文献
964.
The MMPI-2 Superlative (S) scale was developed by Butcher and Han (1995) to assess individuals' tendencies to present themselves in an unrealistically positive light. The current study examined the performance of the L, K, and S scales in accurately distinguishing the MMPI-2 profiles of 379 psychiatric inpatients who produced one or more elevations on the basic scale profiles, from 82 psychiatric inpatients who produced no clinical range elevation on any of the eight basic clinical scales (excluding scales 5 and 0). The findings from the present study indicate that the S scale appears to be effective in the identification of defensiveness among psychiatric inpatients, with mean effect sizes in the moderate to large range. The optimal T-score cutoff for identifying defensive responders was 70 for both men and women. Further, results of hierarchical regression analyses showed that the S scale added incrementally to the prediction levels achieved by the optimal combination of the L and K scales. 相似文献
965.
Substantial evidence suggests that alterations in noradrenergic function contribute to the cognitive impairments of schizophrenia. Activation of post-junctional alpha 2a-adrenergic receptors in the prefrontal cortex by the alpha 2a-selective agonist guanfacine has demonstrated some preliminary benefit in subjects with schizophrenia treated with atypical antipsychotics. alpha 1-adrenergic receptor activity may be less important in mediating the cognitive impairments of schizophrenia. beta-adrenergic receptors may serve as another potential target for cognitive remediation in schizophrenia. However, the potential increase in memory consolidation in schizophrenia patients produced by beta-adrenergic agonists may be outweighed by the impairment in cognitive flexibility and executive functioning produced by beta-adrenergic agonists. Finally, norepinephrine reuptake inhibitors, such as atomoxetine, hold promise as potential cognitive enhancers in schizophrenia because of their ability to indirectly but selectively increase extracellular dopamine concentrations in the prefrontal cortex. 相似文献
966.
Sauser WI 《Science and engineering ethics》2004,10(2):337-342
Without question “business ethics” is one of the hot topics of the day. Over the past months we have seen business after business
charged with improper practices that violate commonly-accepted ethical norms. This has led to a loss of confidence in corporate
management, and has had severe economic consequences. From many quarters business educators have heard the call to put more
emphasis on ethical practices in their business courses and curricula. Engineering educators are also heeding this call, since
the practice of engineering usually involves working for (or leading) a business and/or engaging in business transactions.
In the summer of 2002, Auburn University’s Engineering Professional Development program made the decision to produce—based
on the author’s Executive MBA course in Business Ethics—a distance-delivered continuing education program for professional
engineers and surveyors. Participants across the USA now may use the course to satisfy continuing education requirements with
respect to professional licensing and certification. This paper outlines the purpose and content of the course and describes
its production, distribution, application, and evaluation.
An earlier version of this paper was presented at the “Ethics and Social Responsibility in Engineering and Technology” meeting,
New Orleans, 2003. 相似文献
967.
Switching between spatial stimulus-response mappings: a developmental study of cognitive flexibility
Four different age groups (8-9-year-olds, 11-12-year-olds, 13-15-year-olds and young adults) performed a spatial rule-switch task in which the sorting rule had to be detected on the basis of feedback or on the basis of switch cues. Performance errors were examined on the basis of a recently introduced method of error scoring for the Wisconsin Card Sorting Task (WCST; Barcelo & Knight, 2002). This method allowed us to differentiate between errors due to failure-to-maintain-set (distraction errors) and errors due to failure-to-switch-set (perseverative errors). The anticipated age differences in performance errors were most pronounced for perseverative errors between 8-9 years and 11-12 years, but for distraction errors adult levels were not reached until 13-15 years. These findings were interpreted to support the notion that set switching and set maintenance follow distinct developmental trajectories. 相似文献
968.
Fischer H Fransson P Wright CI Bäckman L 《Cognitive, affective & behavioral neuroscience》2004,4(3):326-334
Blood-oxygenation-level-dependent signal was measured with functional magnetic resonance imaging in 24 healthy young subjects
(12 men and 12 women) during viewing of angry, fearful, and neutral male and female face pictures. Exposure to angry male
as opposed to angry female faces activated the visual cortex and the anterior cingulate gyrus significantly more in men than
in women. A similar sex-differential brain activation pattern was present during exposure to fearful but not neutral faces.
Previous behavioral studies indicate enhanced physiological arousal in men but not in women during exposure to angry male
as opposed to female faces, and brain imaging studies have shown that the occipital cortex and the anterior cingulate gyrus
are influenced by activity in the autonomic nervous system as well as by visual attention. Hence, we suggest that the elevated
occipital and anterior cingulate activation in men during confrontation with other angry and fearful males may reflect enhanced
vigilance in a potentially dangerous situation. 相似文献
969.
970.
DeShon RP Kozlowski SW Schmidt AM Milner KR Wiechmann D 《The Journal of applied psychology》2004,89(6):1035-1056
When working as a member of a team, individuals must make decisions concerning the allocation of resources (e.g., effort) toward individual goals and team goals. As a result, individual and team goals, and feedback related to progress toward these goals, should be potent levers for affecting resource allocation decisions. This research develops a multilevel, multiple-goal model of individual and team regulatory processes that affect the allocation of resources across individual and team goals resulting in individual and team performance. On the basis of this model, predictions concerning the impact of individual and team performance feedback are examined empirically to evaluate the model and to understand the influence of feedback on regulatory processes and resource allocation. Two hundred thirty-seven participants were randomly formed into 79 teams of 3 that performed a simulated radar task that required teamwork. Results support the model and the predicted role of feedback in affecting the allocation of resources when individuals strive to accomplish both individual and team goals. 相似文献