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Assessment and treatment of covert self-injurious behavior are complicated because it is difficult to quantify and apply differential consequences to covert responses. In this study, both tangible and social reinforcers were identified using reinforcer assessment methods. These reinforcers were then provided contingent upon the absence of tissue damage identified during physical examinations, resulting in near 100% success in physical assessment checks that was maintained over 10 months.  相似文献   
114.
This study assessed the applicability of Tyler and Lind's (1992) relational model of authority to the context of local government policies on solid waste management. Tests of the hypothesized relations proposed by Tyler and Lind, accomplished through structural equation modeling, revealed that our data supported the relations between the various constructs of the model. Perceptions of both process control and relational process were found to be positively related to procedural fairness judgments, while procedural fairness judgments were weakly related to evaluations of government entities. Contrary to our expectations, a similar structural equation model test of an extension of the Tyler and Lind model showed that the model constructs were unrelated to respondents' opinions of public policies. The results also indicated that respondents living in communities with different infrastructures and political climates differed slightly in their perceptions of procedural justice and related constructs, but did not differ in their endorsement of the various solid waste management policies.  相似文献   
115.
Residence time and choice in concurrent foraging schedules   总被引:2,自引:2,他引:0       下载免费PDF全文
Five pigeons were trained on a concurrent-schedule analogue of the “some patches are empty” procedure. Two concurrently available alternatives were arranged on a single response key and were signaled by red and green keylights. A subject could travel between these alternatives by responding on a second yellow “switching” key. Following a changeover to a patch, there was a probability (p) that a single reinforcer would be available on that alternative for a response after a time determined by the value of λ, a probability of reinforcement per second. The overall scheduling of reinforcers on the two alternatives was arranged nonindependently, and the available alternative was switched after each reinforcer. In Part 1 of the experiment, the probabilities of reinforcement, ρred and ρgreen, were equal on the two alternatives, and the arranged arrival rates of reinforcers, λred and λgreen, were varied across conditions. In Part 2, the reinforcer arrival times were arranged to be equal, and the reinforcer probabilities were varied across conditions. In Part 3, both parameters were varied. The results replicated those seen in studies that have investigated time allocation in a single patch: Both response and time allocation to an alternative increased with decreasing values of λ and with increasing values of ρ, and residence times were consistently greater than those that would maximize obtained reinforcer rates. Furthermore, both response- and time-allocation ratios undermatched mean reinforcer-arrival time and reinforcer-frequency ratios.  相似文献   
116.
In previous experiments on event-related potentials (ERPs) during linguistic judgments, the subjects' decisions have been categorical (e.g., true vs false). In this experiment, more realistic variations in truth value and subject certainty were used. Thirty-eight naive undergraduates read a story about a fictional murder. ERPs were recorded as the subjects rated the strength of their beliefs about statements relating to suspects in the crime. Because no subject was sure which of the suspects was guilty of committing the crime, binary (true–false) category judgments were inappropriate. Three components of the ERP waveforms were affected by the experimental manipulations. An early positive component was largest to sentences concerning the suspect considered most likely to have committed the crime. A subsequent broad posterior positivity (LPC) also showed significant sentence-type differences, but it was larger to sentences considered probable—whether they were true or false—than to more ambiguous sentences. A third ERP component (N400) was negative at midline electrode sites and peaked at approximately 420 ms. Subjects' truth-value judgments had no effect on the N400. N400 was, however, affected by the subject's task. It was more negative when subjects made graded judgments about truth value than when they made binary true–false judgments. Overall, naturalistic judgments of sentence validity produced a variety of brain responses that reflected different aspects of linguistic decision making.  相似文献   
117.
Developmental stuttering (DS) may be related to the extrapyramidal motor system and shares many clinical similarities with Tourette's syndrome (TS), which is widely believed to be associated with extrapyramidal dysfunction. Twenty-two stutterers were examined for neuropsychiatric features commonly seen in TS, including tics, obsessive-compulsive behaviors (OCB), and attention deficit disorders. Eleven stutterers displayed motor tics, and symptoms of OCB were observed at rates similar to those seen in persons with TS. Few stutterers demonstrated significant attentional deficits. Findings are consistent with models suggesting extrapyramidal involvement in DS and raise the possibility that DS and TS are pathogenetically related.  相似文献   
118.
How similar are the meanings of facial expressions of emotion and the emotion terms frequently used to label them? In three studies, subjects made similarity judgments and emotion self-report ratings in response to six emotion categories represented in Ekman and Friesen's Pictures of Facial Affect, and their associated labels. Results were analyzed with respect to the constituent facial movements using the Facial Action Coding System, and using consensus analysis, multidimensional scaling, and inferential statistics. Shared interpretation of meaning was found between individuals and the group, with congruence between the meaning in facial expressions, labeling using basic emotion terms, and subjects' reported emotional responses. The data suggest that (1) the general labels used by Ekman and Friesen are appropriate but may not be optimal, (2) certain facial movements contribute more to the perception of emotion than do others, and (3) perception of emotion may be categorical rather than dimensional.  相似文献   
119.
In light of information uncovered about human radiation experiments conducted during the Cold War, an important charge for the Advisory Committee on Human Radiation Experiments was to assess the current state of protections for human research subjects. This assessment was designed to enhance the Committee's ability to make informed recommendations for the improvement of future policies and practices for the protection of research subjects. The Committee's examination of current protections revealed great improvement over those from the past, yet some problems remain. Although the data collected by the Committee highlight specific areas in need of attention, the Committee's work should be viewed in part as the beginning of a series of ongoing assessments of the adequacy and effectiveness of the protections afforded to human subjects.  相似文献   
120.
The available literature indicates that: (a) experiences of childhood violence are associated with mediator variables, including antisocial behaviors and depressive symptomatology, that are themselves associated with development of alcohol problems and perpetration of partner violence for men in adulthood; (b) experiences of childhood violence and, more strongly, observation of interparental violence during childhood predict perpetration of partner violence in adulthood for males; (c) presence of partner violence is associated with certain types of alcohol problems for men; and (d) both partner violence and alcohol problems are associated with marital conflict. However, available research has often excluded important moderator variables, such as history of familial and parental alcohol problems and history of parental psychiatric disorders. Based on the available research, two indirect pathways between childhood violence and adulthood problems (i.e., alcohol problems and partner violence) are proposed as guides for future research in the areas of family violence and alcohol problems for men. Further, bidirectional associations between alcohol problems and partner violence are proposed. Finally, inclusion of important moderator and mediator variables in multivariate research designs is suggested.  相似文献   
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