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951.
952.
In Experiment 1, rats were trained on either a random-interval or a variable-interval 60-sec schedule of reinforcement, and reinforcement magnitude was varied across conditions between one and four pellets. Although the two schedules maintained different patterns of behaviour, patterns and rates of responding were not systematically affected by the variation in reinforcement magnitude. In Experiment 2, a regulated probability interval schedule that generated similar rates of reinforcement to those of the schedules of Experiment 1 was used, with the pattern of behaviour generated resembling that typical of a random-interval schedule. Changing reinforcement magnitude again produced few systematic changes in behaviour. In Experiment 3, a variable-ratio schedule was used within a procedure that otherwise resembled that of Experiments 1 and 2. Increasing the reinforcement magnitude now decreased the rates of responding, and examination of the patterns of responding showed that this came about because rates of responding were higher early in the interreinforcer interval in the one-pellet condition. These experiments demonstrate the insensitivity of behaviour under interval schedules to changes in reinforcement magnitude and suggest the operation of mechanisms different from those engaged by ratio schedules and discretetrial learning procedures.  相似文献   
953.
C. R. Gallistel   《Cognition》1994,50(1-3):151-170
The self-stimulating rat performs foraging tasks mediated by simple computations that use interreward intervals and subjective reward magnitudes to determine stay durations. This is a simplified preparation in which to study the neurobiology of the elementary computational operations that make cognition possible, because the neural signal specifying the value of a computationally relevant variable is produced by direct electrical stimulation of a neural pathway. Newly developed measurement methods yield functions relating the subjective reward magnitude to the parameters of the neural signal. These measurements also show that the decision process that governs foraging behavior divides the subjective reward magnitude by the most recent interreward interval to determine the preferability of an option (a foraging patch). The decision process sets the parameters that determine stay durations (durations of visits to foraging patches) so that the ratios of the stay durations match the ratios of the preferabilities.  相似文献   
954.
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956.
This paper addresses a problem in reporting scientific research. The problem is how to distinguish between justifiable and unjustifiable data selection. Robert Millikan is notorious for an infamous remark that he used all his data when in fact he had used a selection. On this basis he has been accused of fraud. There is a tension here — historians and his defenders see his selection as understandable and legitimate, while current statements about the Responsible Conduct of Research imply his selection was illegitimate. This paper discusses two main issues that arise in assessing his conduct, whether he was intentionally misleading and whether he actually did mislead the scientific community about some facts of nature. It is argued that he was not intentionally misleading, and that it is unlikely that he misled the scientific community.  相似文献   
957.
The study compared the effect of five persuasive appeals used in AIDS PSAs and condom commercials (fear arousal-no sex/condom theme; fear arousal-sex/condom theme; erotic; humorous; factual) on 122 male and 114 female college students' i]ntentions to use and taking of condoms. Results showed that the two fear appeals were more effective than other appeals in increasing intentions to use condoms with a new partner. The fear appeal–no sex/condom theme was more effective than other appeals for increasing intentions to use condoms with a steady partner. Compared to men, women rated commercials as more effective for increasing intentions to use condoms with a new partner. Persuasive appeals had no effect on the taking of free condoms. The best predictor of commercial effectiveness was the degree to which a commercial evoked a high fear of AIDS. Other significant predictors were subjects' a]ttitude toward condom use and commercial qualities of being humorous, romantic, credible, and factual. Implications are that all five types of appeals are potentially effective for use in AIDS PSAs. Recommendations include combining appeals (e.g. fear with erotic) and emphasizing the positive features of condom use.  相似文献   
958.
Currently, most exposure-based treatments call for clinicians to assess for and remove all safety behaviors during exposure tasks. However, the notion that safety behaviors are detrimental across all scenarios has recently been challenged, and research regarding the effects of safety behaviors on exposure outcomes is limited and inconsistent. In clinical practice, classifying a strategy as a safety behavior can be a complex and challenging endeavor, particularly when distinguishing between harmful safety behaviors and helpful coping behaviors. We outline an approach that emphasizes the pragmatic truth criterion and uses functional outcomes to classify behaviors as serving either safety or coping functions. Our focus on doing what “works” simplifies decision-making for clinicians and maintains the focus of treatment on enhancing functioning. We propose a model for using functional outcomes to distinguish between safety and coping behaviors and illustrate our approach through case examples.  相似文献   
959.
The objective of this study was to use qualitative methodology to tailor and refine an existing smoking cessation intervention for the population of people who use cigarettes and are diagnosed with schizophrenia, schizoaffective, or psychotic disorder. Successive cohort design methodology was used to iteratively modify the treatment in response to qualitative participant, therapist, and consultant feedback on the intervention. Qualitative methodology for participant feedback included analysis of semistructured interviews with participants, visualization of app utilization data, and stakeholder feedback from study therapists and consultants. Using the successive cohort design, a tailored multicomponent mobile health smoking cessation intervention was developed. The intervention included mobile contingency management (i.e., financial compensation for confirmed abstinence from smoking), pharmacotherapy for smoking cessation, cognitive-behavioral counseling sessions, and the Stay Quit app for relapse prevention. Two cohorts (N = 13) were completed in the study; after each cohort, the treatment protocol was revised. The intervention is described, as well as the qualitative findings from each cohort and subsequent changes made to the intervention based upon patient and provider feedback. Metrics of patient engagement included treatment adherence (40% in Cohort 1 and 63% in Cohort 2). Both participants and therapists reported that the intervention was helpful. Over one third of participants self-reported abstinence at posttreatment. Since qualitative methodology is often underutilized in mental health treatment development, this study demonstrates the utility of the successive cohort design for treatment development of behavior change interventions for at-risk, vulnerable populations.  相似文献   
960.
Initially conceived as an alternative to abstinence-based approaches, the initial goal of harm-reduction was to reduce the health consequences of drug use. Applied to all addictive behaviors (with or without use), it aims to reduce the individual and social problems generated by addiction without condemning the behavior. Harm-minimisation remained very poor in the gambling field. However, the legalization of online gambling in France and their specific characteristics, update the need to develop this field, which is still a new and relatively uncommon part of harm-reduction. The aim of this article is to draw up an inventory of existing knowledge, whether it has been tested empirically or not, in an ecological environment or in a laboratory situation, as regards tools allowing the player to remain in control of his gambling behavior. A reflection on future research and other possible tools is envisaged.  相似文献   
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