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21.
For over 20 years the medical literature has carefully documented the undertreatment of all types of pain by physicians. During this same period, as the field of bioethics came of age, the phenomenon of undertreated pain received almost no attention from the bioethics literature. This article takes bioethicists to task for failing to recognize the undertreatment of pain as a major ethical, and not merely a clinical, failing of the medical profession. The nature and extent of the problem of undertreated pain is examined, as well as possible reasons for its disregard by bioethicists. The factors contributing to undertreated pain in the clinical setting are considered, as well as the hazards posed by recent failures to address ethically questionable clinical practices. Finally, suggestions are offered for refocusing the attention of bioethicists to this significant problem.  相似文献   
22.
Traditional studies of deterrence have focused on punishment with less regard for the rewards of both crime and noncrime. Influenced by work in economics and behavioral psychology, more recent studies have departed from tradition by incorporating rewards for crime. To this extent, they should be regarded as advances over the more traditional approaches. Notwithstanding these advances, variations in both the probability and magnitude of reward for noncrime have not been systematically included in these more recent theories of choice. In an attempt to determine whether opportunities for noncrime are either central or trivial to the criminal decision-making process, the present study fitted two alternative models to experimental data involving risk-taking: (a) the economic utility model employed by Piliavin, Gartner, Thornton, and Matsueda (1986) in their study of criminal choice; and (b) the satisfaction balance model developed by Gray and Tallman (1984). Results showed that while both models explained significant amounts of variation in the dependent variable, the Gray-Tallman model provided a substantially better fit of the data. Despite limitations inherent in experimental studies as, for example, limitations surrounding the issue of external validity, the findings strongly suggest that opportunities for noncrime are as important as rewards and costs for crime in the process by which criminal decisions are made.  相似文献   
23.
Methodological difficulties are identified in the assessment of children's comprehension of relative clauses (RCs) by means of the standard acting-out procedure. An alternative experimental task is proposed which attempts to minimize these difficulties while exploring the advantages of the acting-out technique. An experiment is reported in which Portuguese-speaking 3- to 6-year olds were tested by means of this alternative task. The results show children being affected by both the position and the focus of the RC in the same way adults have been reported to be and an error analysis suggests that most of children's difficulties can be ascribed to memory overload while RCs are processed as noun modifier sentences. These results contradict the view that there are developmental differences with regard to the way sentences with RCs are parsed and that processing load induces errors particularly manifested in right-branching subject focus sentences. Developmental changes taking place between the ages of 3 and 6 are considered and questions are raised concerning development from the age of 5.The research reported here was carried out while the author read for the PhD degree at the University of London. The writing up of this paper was financially supported by a postdoctoral grant from the Brazilian Research Council (CNPq: 302103-86.4).  相似文献   
24.
Mental models constitute an alternative to the rule-based systems in the explanation of human reasoning (Johnson-Laird, 1983). In this paper, we claim that the concept of believability generally used to categorize content and context effects is of little use within a semantic theory. Thus, we propose the use of categories that are directly extracted from subjective relations among concepts within the reasoning problem. We demonstrate that manipulations based on this kind of categorization produce predictable patterns of responses in reasoning problems. We present two experiments to test our predictions, using conditional and syllogistic reasoning problems, and in both cases, we demonstrate the influence of conceptual knowledge not only in natural contexts, but also in experimentally created artificial contexts.  相似文献   
25.
Rats were trained on an appetitive discriminated operant procedure according to a blocking design, in which training with a compound stimulus (A + B) was given with or without prior training with A alone. Stimulus B was then presented in compound with a new stimulus (B + C compound). The ability of Stimulus B to block acquisition of control by Stimulus C was decreased by B having itself been blocked by A during the prior training. The results imply that the mechanism of blocking during the initial blocking procedure was a reduced association between Stimulus B and the reinforcer, and not a performance deficit such as that postulated by comparator models of learning.  相似文献   
26.
In the experiment reported here the primary hypothesis proposed, which was supported by the data, was that subjects performing a two-choice self-paced serial RT task would learn to change their strategy of perceptual analysis of signals presented to them as they became progressively more practised. Early in practice each signal is identified as a particular state of the display and an appropriate response is then made. Well practised subjects, however, select their responses by reference to the change or constancy between successive displays. This strategy implies that the assumptions made by the generally accepted simple S-R connectionist model of two-choice serial RT may be quite misleading, since the choice of any particular response must be determined not only by the display state but also by what the previous response had been.  相似文献   
27.
The Hatfield Polytechnic, Hatfield, Herts ALIO 9AB, England The experiment utilized a serial choice reaction time (RT) paradigm in which only one alphanumeric stimulus was presented per trial, and the target set consisted of a single identified item. The categorical relationship between the target and nontarget items was varied as a property of blocks of trials. Target and nontarget RTs were smaller when the specified target item (e.g., the number 6) was categorically distinct from the nontargets (e.g., letters) than when it was from the same category (e.g., digits). The processing of catch-trial stimuli (items from the alternate category to the nontargets) and homographie category-ambiguous items was inhibited only in the former, between-category, condition. The results are contrasted with those obtained in visual search tasks. They suggest that a “locational-cue” explanation of alphanumeric category effects is inadequate.  相似文献   
28.
A single-subject experimental design was used to investigate the feasibility of applying non-invasive laboratory instrumentation for examining speech physiology to assessment and biofeedback-based remediation of stuttering. Physiologic assessment facilitated the development of behavioral goals directed at changing respiratory and phonatory behaviors for this subject. Visual biofeedback therapy produced reduction in respiratory discontinuities and increased phonatory continuity, concomitant with reduced perceivable molar dysfluency. Methods used in this case illustrate a variety of options and problems related to clinical use of instrumentation. Results suggest that signals which represent respiratory, phonatory, and articulatory physiologic events may be clinically practical for evaluating and altering perceivable dysfluency.  相似文献   
29.
Two experiments examined the effects of several types of repetition on state-dependent memory for conceptually categorized words. In both experiments, compatibility between pharmacological states at encoding and at retrieval facilitated the uncued recall of nonrepeated categories but had no appreciable effect on the recall of words within recalled categories. In both experiments, compatibility between encoding/retrieval states failed to facilitate the uncued recall of repeated categories li.e., categories whose names and/or exemplars were presented at least twice, in a constant or variable order, and with substantial spacing between successive presentations). And again, in both experiments, the level of uncued recall was higher for repeated than for nonrepeated categories, irrespective of the compatibility or incompatibility of encoding/retrieval states. These findings, together with other relevant observations reported in the literature, suggest that repetition in general, and repetition of category names in particular, influences recall in much the same ways as does explicit cuing with category names: It enhances the accessibility of higher order units, as reflected in uncued category recall, and it diminishes to the extent to which access to these units is state dependent.  相似文献   
30.
The correlation between short-term retention of the outcome of the preceding response and overall learning proficiency was investigated for serial reversal learning. Pigeons were trained to asymptote on a serial reversal problem and then were presented a percentage reinforcement schedule where only some correct trials were rewarded. Nonrewarded correct trials were treated exactly as incorrect trials. The difference in error probability following the two types of correct trials was then used as a measure of short-term retention. When intertrial intervals (ITI) were short (6 sec), substantial differences occurred. When the ITI's were increased, the difference in accuracy declined regularly to no difference at an ITI of 60 sec. This demonstration of a short-term retention gradient, coupled with the finding that overall reversal learning was much better with the shorter ITI's, suggests that a primary mechanism of improvement in serial reversal learning is the acquisition of a conditional discrimination based on the outcome of the preceding response.  相似文献   
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