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71.
72.
The role that costs, benefits, and perceptions of invulnerability play in condom use was examined in a sample of students ( N = 211) at 4-year and 2-year colleges. In multiple regression analyses, past condom use was related to relative invulnerability, low present risk, and inexperience. Less intended condom use was associated with high perceptions of relative invulnerability and low perceptions of present risk. It appears that many college students feel protected from HIV because they judge their current sexual environment to be safe due to monogamy, sexual history taking, and the ability to tell a partner's HIV status. Independent of that, feelings of relative invulnerability are associated with more condom use—perhaps an accurate judgment of past risky behavior.  相似文献   
73.
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   
74.
We investigate under what conditions contrary-to-duty (CTD) structures lacking temporal and action elements can be given a coherent reading. We argue, contrary to some recent proposals, that CTD is not an instance of defeasible reasoning, and that methods of nonmonotonic logics are inadequate since they are unable to distinguish between defeasibility and violation of primary obligations. We propose a semantic framework based on the idea that primary and CTD obligations are obligations of different kinds: a CTD obligation pertains to, or pre-supposes, a certain context in which a primary obligation is already violated. This framework is presented initially as an extension of Standard Deontic Logic (SDL), a normal modal logic of type KD, and is illustrated by application to a series of examples. The concluding section is concerned with some resemblances between CTD and defeasible reasoning. We show first that the SDL-based framework contains a flaw and must be adjusted. A discussion of possible adjustments, including an alternative treatment in terms of a preference-based semantics, reveals difficulties that are reminiscent of problems in defeasible reasoning and intensional accounts of defeasible conditionals.  相似文献   
75.
In the current investigation, 2 participants with mental retardation displayed property destruction and stereotypy, and both responses involved the same materials (e.g., breaking and tapping plastic objects). Three experiments were conducted (a) to indirectly assess the functions of these two responses, (b) to determine their relation to one another, and (c) to develop a treatment to reduce the more serious behavior, property destruction. In Experiment 1, previously destroyed materials were either present or absent, and their presence reduced property destruction but not stereotypy. In Experiment 2, matched toys (ones that produced sensory stimulation similar to stereotypy) were either present or absent, or were replaced by unmatched toys (for 1 participant). Matched toys produced large reductions and unmatched toys produced small reductions in property destruction and stereotypy. In Experiment 3, attempts to pick up undestroyed objects were either blocked or not blocked while matched toys were continuously available. Response blocking reduced property destruction (and attempts), prevented stereotypy, and increased manipulation of matched toys. These results suggest that the two aberrant responses formed a chain (e.g., breaking and then tapping the object), which was maintained by the sensory consequences (e.g., auditory stimulation) of the terminal response, and that previously destroyed material or matched toys made the initial response (property destruction) unnecessary.  相似文献   
76.
In a time of budgetary shortfalls in the medical industry, an aging population, and an increased emphasis on health care choices, psychologists are being called upon to administer advance medical directive programs to patients. This study reports preliminary findings from a program to assess and facilitate patients' knowledge of advance directives (ADs) by the Psychology Service at the Ann Arbor VA Medical Center. The participant pool included 243 male veteran patients admitted to medical and surgical wards at the hospital. The intervention included the use of a computer-generated prompt for consultation, which was sent to the psychology staff in response to a patient inquiry regarding ADs. It also involved an increased emphasis on the delivery of written material on ADs by the admissions clerks. The intervention appeared to result in a modest increase in patients' knowledge of advance directives. Suggestions are offered for areas that should be emphasized in future attempts to increase patients' knowledge and utilization of advance directives.  相似文献   
77.
Considering the findings that schizophrenics have been found to show relatively slow reaction times (RTs), and often do not benefit from ordinarily helpful information (e.g. a warning signal), the present study investigated the relationship between these variables and psychoticism (P). One hundred and three male Ss were administered a questionnaire which provides a measure of P. In addition, all Ss were tested on an RT task under unsignalled (i.e. no warning signal) and signalled conditions. The results showed that the expected improvement in reaction speed with a warning signal was of a lesser magnitude for those high on P. Furthermore, the difference was due to the faster RTs for high P scorers in the unsignalled condition. The data suggest that high P scorers are like schizophrenics in that they show less benefit from a warning signal, but are dissimilar in terms of reaction speed in an unsignalled task.  相似文献   
78.
Two factors, level of processing (Craik & Lockhart, 1972) and congruity (Schulman, 1974), known to have large effects on the recall of experimenter-provided responses to questions, were examined in a series of five incidental learning experiments using subject-generated responses. The data show that manipulation of level of processing has the same effect on recall of subjectgenerated responses as it does on experimenter-provided responses. However, the effect of congruity is reversed for subject-generated responses. The data suggest that the difficulty of generating unrelated responses (“incongruous“ items) may account, at least in part, for the failure of the “principle of congruity“ with subject-generated responses.  相似文献   
79.
The effect of 25 mg or 75 mg of chlorpromazine on the serial reaction performance of 12 male human subjects was studied. Speed or number of correct responses was reduced by the high dose of chlorpromazine and errors of commission and omission were increased. The adverse effect of the drug upon speed appeared only at the end of the half-hour test. By contrast the adverse effect upon gaps and errors was apparent throughout the test and there was no interaction with test duration.  相似文献   
80.
Children 8, 10, and 13 years of age were either given prior experience constructing seriations or matrices with two-dimensional stimuli, or no prior experience. Knowledge of the separation of variables concept was then assessed by examining children's use of controlled tests of a problem variable's effect (probe questions), and recognition of the inadequacy of confounded variable tests (negative counter-suggestion questions). Although many children either passed both questions or failed both questions, a significant number of children correctly used controlled variable tests, and yet failed to recognize the inadequacy of a confounded test. These results suggest that although a preliminary form of the separation of variables concept is characterized by use of controlled variable tests, subsequent refinement of the concept includes recognition of the inadequacy of confounded tests. Relative to seriation, prior experience constructing matrices facilitated recognition of a confounded test's inadequacy. Constructing matrices may have focused attention on the simultaneous variation of problem elements on multiple dimensions and thus facilitated recognition of the necessary role of both variation of stimuli on test dimensions and equality of stimuli on nontest dimensions, e.g., a controlled test.  相似文献   
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