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891.
The aim of the study was to investigate the utility of the Tower of London-Drexel (TOLDX) in assessing the executive deficits associated with Parkinson's disease (PD). We sought to determine whether the TOLDX would differentiate between (a) patients with PD and healthy control participants (HCP), (b) demented and nondemented patients, and (c) depressed and nondepressed patients. A new TOLDX score, stimulus bound, was introduced to assess utilization behaviors. Furthermore, the convergent and divergent validity of the TOLDX was examined. The TOLDX total move, rule and time violation, and stimulus-bound scores of patients with PD significantly differed from the HCP. Demented and nondemented patients also differed significantly in their TOLDX performance, with the stimulus-bound score being the most significantly differentiating score. However, the depressed and nondepressed patients did not differ in their TOLDX performance. Support was found for the convergent and divergent validity of the TOLDX. The clinical and theoretical implications of the findings are discussed. 相似文献
892.
There is a high prevalence of psychological disorders among adolescents in detention facilities. The need for a simple, effective screening tool led to the development of the Massachusetts Youth Screening Instrument (MAYSI) and its successor, the MAYSI-2. This study evaluated the MAYSI-2 psychometric properties based on the records of 704 youths evaluated at intake to detention facilities. In addition to factor structure, the study evaluated test-retest reliability and concurrent external validity. Results were generally encouraging in terms of the use of MAYSI-2 in detention facilities, and directions for future research are discussed. 相似文献
893.
Forge J 《Science and engineering ethics》2004,10(3):531-542
I ask whether weapons research is ever justified. Weapons research is identified as the business of the engineer. It is argued
that the engineer has responsibility for the uses to which the tools that he designs can be put, and that responsibility extends
to the use of weapons. It is maintained that there are no inherently defensive weapons, and hence there is no such thing as
‘defensive’ weapons research. The issue then is what responsibilities as a professional the engineer has in regard to such
research. An account is given to ground the injunction not to provide the means to harm as a duty for the engineers. This
account is not, however, absolutist, and as such it allows justifiable exceptions. The answer to my question is thus not that
weapons research is never justified but there must be a strong assurance that the results will only be used as a just means
in a just cause. 相似文献
894.
Hale LR Goldstein DS Abramowitz CS Calamari JE Kosson DS 《Behaviour research and therapy》2004,42(6):697-710
Although the hypothesis that psychopathic individuals are characterized by a reduced capacity for experiencing anxiety is central to many theories of psychopathy, most prior studies have examined anxiety and fear measures generally considered outdated in the literature. Moreover, prior findings are mixed, with several studies reporting no relationships between psychopathy and anxiety, and others suggesting negative relationships for the affective, interpersonal aspects of the disorder and positive relationships for the antisocial behavior dimension. To examine whether psychopathy dimensions are associated with contemporary measures of anxiety, the Anxiety Sensitivity Index and State Trait Anxiety Inventory-Trait scale were administered to 157 male inmates. Participants also completed the MMPI-derived Welsh Anxiety Scale (WAS), commonly used in psychopathy studies. Analyses provide no evidence for a negative relationship between psychopathy's affective, interpersonal factor and anxiety sensitivity after controlling for trait anxiety. Trait anxiety and WAS scores were positively associated with the antisocial behavior dimension of psychopathy. Findings do replicate prior relationships between the WAS and psychopathy, suggesting the WAS may measure aspects of negative affectivity that differ from anxiety. 相似文献
895.
Plucker JA Robinson NM Greenspon TS Feldhusen JF McCoach DB Subotnik RF 《The American psychologist》2004,59(4):268-9; author reply 269-71
896.
The authors investigate a previously overlooked yet important objective for employee job search--seeking leverage against the current employer. They explore the outcomes and correlates of leverage-seeking search and how it may differ from the more traditional objective for engaging in job search--to change jobs. Results show that leverage-seeking and separation-seeking search objectives associate with different outcomes. The authors also find that characteristics of the work situation and individual differences associate with leverage-seeking search and relate differently with the 2 job search objectives. Implications for practice and the advancement of job search research are discussed. 相似文献
897.
Effects of anorectic drugs on food intake under progressive-ratio and free-access conditions in rats
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The effects of two anorectic drugs, dexfenfluramine and phentermine, on food intake under different food-access conditions were examined. Experiment 1 compared the effects of these drugs on food intake under a progressive-ratio (PR) schedule and free-access conditions. Dexfenfluramine decreased food intake under both conditions, but the doses required to decrease intake under free-access conditions were higher than those required to reduce intake under the PR condition. Intermediate doses of phentermine sometimes increased breaking points, and higher doses decreased them. Phentermine decreased food intake at the same doses under both access conditions. Thus the potency of dexfenfluramine, but not phentermine, to decrease food-maintained behavior depended upon the food-access condition. Experiment 2 used a novel mixed progressive-ratio schedule of food delivery to study the duration of drug effects. Sessions consisted of five components separated by 3-hr timeouts. The ratio requirement reset at the beginning of each component and a new breaking point was obtained. Both dexfenfluramine and phentermine dose-dependently decreased breaking points early in the session. In some rats, compensatory increases in breaking point were observed. That is, breaking points later in the session increased over control levels, resulting in no change in the total number of food pellets earned for the session compared to control. The present findings suggest that the effects of some anorectic drugs depend upon the access conditions for food; increasing the effort to obtain food may enhance their ability to decrease food-maintained behavior. 相似文献
898.
Choice typically is studied by exposing organisms to concurrent variable-interval schedules in which not only responses controlled by stimuli on the key are acquired but also switching responses and likely other operants as well. In the present research, discriminated key-pecking responses in pigeons were first acquired using a multiple schedule that minimized the reinforcement of switching operants. Then, choice was assessed during concurrent-probe periods in which pairs of discriminative stimuli were presented concurrently. Upon initial exposure to concurrently presented stimuli, choice approximated exclusive preference for the alternative associated with the higher reinforcement frequency. Concurrent schedules were then implemented that gave increasingly greater opportunities for switching operants to be conditioned. As these operants were acquired, the relation of relative response frequency to relative reinforcement frequency converged toward a matching relation. An account of matching with concurrent schedules is proposed in which responding exclusively to the discriminative stimulus associated with the higher reinforcement frequency declines as the concurrent stimuli become more similar and other operants-notably switching-are acquired and generalize to stimuli from both alternatives. The concerted effect of these processes fosters an approximate matching relation in commonly used concurrent procedures. 相似文献
899.
In a change detection paradigm, the global orientation of a natural scene was incrementally changed in 1 degree intervals. In Experiments 1 and 2, participants demonstrated sustained change blindness to incremental rotation, often coming to consider a significantly different scene viewpoint as an unchanged continuation of the original view. Experiment 3 showed that participants who failed to detect the incremental rotation nevertheless reliably detected a single-step rotation back to the initial view. Together, these results demonstrate an important dissociation between explicit change detection and visual memory. Following a change, visual memory is updated to reflect the changed state of the environment, even if the change was not detected. 相似文献
900.
Observers can sight a target 20 m away or more and then walk to it accurately without vision. In contrast to this good performance, this article shows that walked indications of the exocentric separation of two locations exceed the required values by over 70% when vision is obscured. Significantly, these large errors are coupled with a robust lack of depth foreshortening, even under conditions in which visual matches and verbal estimates of extent exhibit strong evidence of depth compression. This article presents evidence that the overshooting errors are due largely to recalibration of locomotor control produced by prolonged exposure to nonvisual walking. The robust lack of depth foreshortening, meanwhile, could reflect a corresponding isotropy in the spatial representation controlling the walking response. More research is needed to confirm this interpretation, however. 相似文献