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991.
Previous work suggests that there may be fundamental differences between compensatory stepping responses evoked by postural perturbation and visually cued "volitional" stepping (e.g., gait initiation). In contrast to visual cueing, postural destabilization evokes an array of sensory inputs that are intrinsically linked to the mobilization of rapid compensatory responses. The hypothesis examined in this study was that this fundamental difference would lead to distinct changes in the temporal characteristics of the stepping response. Six healthy young adults were instructed to step quickly in response to either visual cueing or anterioposterior platform motion. Both forward and backward stepping responses were characterized, using measures of vertical ground reaction force. A stereotypical temporal patterning of the stepping response occurred in both stimulus conditions and both directions of stepping, and anticipatory postural adjustments were evident in all trials. However, postural destabilization led to a more rapid initiation and execution of the temporal pattern, in comparison with visually cued responses. The most pronounced effect was seen in the duration of the response, which was reduced by a factor of two, with approximately proportional foreshortening of both the preparatory and swing phases. The results suggest that sensory information conveying a state of instability has a distinct influence on the characteristics of a subsequent stepping reaction. The persistence of the anticipatory postural adjustments suggests that the failure to see this element of the response in previous studies may reflect fundamental differences between volitional and unplanned compensatory stepping.  相似文献   
992.
We compared Minnesota Multiphasic Personality Inventory (MMPI-2) results from 2 groups of mildly to moderately disturbed psychiatric outpatients (N=60) answering under either Standard or Cry for Help instructions. Results from previously completed intake MMPI-2 protocols were obtained for each participant. The two groups were comparable on intake MMPI-2 variables and demographic characteristics. Analysis of feedback data from the second, experimental observation indicated that the two groups had equivalent self-estimates of understanding of their role and success in simulating their role. Significant differences were found between the two groups on their experimental MMPI-2 protocols. The Cry for Help group had significantly higher scores on F, F-K, Fb, Ds2, and Fp scales as well as significantly lower scorns on the K scale. The Cry for Help group also had significantly higher scores on all clinical scales with the exception of 5, which was not tested. Cutting scores derived by Rogers, Sewell, and Ustad (1995) for the detection of a Cry for Help in outpatients were cross-validated with fairly positive results. Although these results are promising, particularly in light of the shrinkage expected on cross-validation, further research is needed in this area.  相似文献   
993.
In two experiments, patterns of response error during a timing accuracy task were investigated. In Experiment 1, these patterns were examined across a full range of movement velocities, which provided a test of the hypothesis that as movement velocity increases, constant error (CE) shifts from a negative to a positive response bias, with the zero CE point occurring at approximately 50% of maximum movement velocity (Hancock & Newell, 1985). Additionally, by examining variable error (VE), timing error variability patterns over a full range of movement velocities were established. Subjects (N = 6) performed a series of forearm flexion movements requiring 19 different movement velocities. Results corroborated previous observations that variability of timing error primarily decreased as movement velocity increased from 6 to 42% of maximum velocity. Additionally, CE data across the velocity spectrum did not support the proposed timing error function. In Experiment 2, the effect(s) of responding at 3 movement distances with 6 movement velocities on response timing error were investigated. VE was significantly lower for the 3 high-velocity movements than for the 3 low-velocity movements. Additionally, when MT was mathematically factored out, VE was less at the long movement distance than at the short distance. As in Experiment 1, CE was unaffected by distance or velocity effects and the predicted CE timing error function was not evident.  相似文献   
994.
Relationships among children's affective expression in fantasy play, interpersonal themes in projective stories, and concurrent interpersonal behaviors were investigated in 49 children. Participants completed a play task, a projective storytelling task, and a brief IQ measure. Peer and teacher ratings provided measures of interpersonal functioning. Results found that access to and comfort with affect is related to the ability to think in interpersonal ways. Neither affective expression in play nor interpersonal themes in projective stories were related to actual interpersonal behavior.  相似文献   
995.
Pigeons were trained to peck a key on a variable-interval 2-min schedule of food reinforcement. Prior to each session, either 2.0 mg/kg methadone (n = 3), 3.0 mg/kg cocaine (n = 4), or 5.6 mg/kg cocaine (n = 2) was administered. When each pigeon's rate of pecking was stable, a range of doses of the training drug and saline were administered prior to 20-min extinction sessions separated by at least four training sessions. Rate of pecking during these extinction tests was generally an increasing function of dose, with the lowest rates obtained following saline and low doses and the highest rates obtained following doses near the training doses. Dose functions from pigeons trained with 5.6 mg/kg cocaine were steeper than those from pigeons trained with 3.0 mg/kg cocaine. Pigeons trained with methadone or 3.0 mg/kg cocaine were then given discrimination training, in which food reinforcement followed drug administration and 20-min extinction sessions followed saline administration. Rates of pecking under these conditions quickly diverged until near-zero rates were obtained following saline and high rates were obtained following drug. Discrimination training steepened dose functions for the training drugs, and the effects of several other substituted drugs depended on the pharmacology of the training drug. The pigeons trained with 5.6 mg/kg cocaine were tested with d-amphetamine, methadone, and morphine prior to discrimination training. d-Amphetamine increased rates dose dependently, and methadone and morphine did not. The results suggest that discriminative control by methadone and cocaine was established without explicit discrimination training.  相似文献   
996.
Inappropriate sexual behavior by professionals has been reported in increasing numbers. This article focuses on the cognitive-behavioral treatment of clergy who have acted out sexually. Case studies are used to identify the various issues and facets of treatment. The article concludes with a program designed to return previously offending clergy to active roles within their denominations is described.  相似文献   
997.
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999.
Aristotle's illustrations of the fallacy of Figure of Speech (or Form of Expression) are none too convincing. They are tied to Aristotle's theory of categories and to peculiarities of Greek grammar that fail to hold appeal for a contemporary readership. Yet, upon closer inspection, Figure of Speech shows many points of contact with views and problems that inhabit 20th-century analytical philosophy. In the paper, some Aristotelian examples will be analyzed to gain a better understanding of this fallacy. The case of the Third Man argument and some modern cases lend plausibility to the claim that Figure of Speech is of more interest as a type of fallacy than has generally been assumed. Finally, a case is made for the view that Figure of Speech, though listed among the fallacies dependent upon language, is not properly classified as a fallacy of ambiguity. More likely, it should be looked upon as a type of non sequitur. This has important consequences for the profile of dialogue associated with this fallacy.  相似文献   
1000.
This paper describes the development and validation of a personnel selection instrument designed to predict employee tenure. The instrument was developed using models of employee turnover, psychodynamic theory, and beliefs regarding the optimal way to advance one's career. Four predictive designs were conducted to validate the instrument. Correlation coefficients ranged from .14 (p < .07) to .28 (p < .05) in predicting tenure.  相似文献   
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