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21.
Effects of pentobarbital on fixed-ratio reinforcement,   总被引:1,自引:1,他引:0       下载免费PDF全文
Certain doses of pentobarbital consistently increased the rate of pecking engendered by a fixed-ratio schedule of 30 responses in a group of 13 pigeons, and still higher doses produced decrements in rate of responding. For individual subjects, the dose-effect functions were qualitatively similar, but differed with respect to the doses producing the maximum increase and subsequent decrease in rate. In general, the maximum occurred at lower doses and the decrement was greater at the highest dose in the birds with the highest control rates. It was also possible to distinguish between the effects of pentobarbital and several other drugs on the behavior maintained by FR 30. The results indicate that changes in rate of responding on FR 30 after drug administration are dose-dependent, drug-specific effects.  相似文献   
22.
Two dogs were maintained on a multiple schedule having both a food reinforced and an avoidance component (Mult VI 1′ SΔ AvoidSS20 RS20 SΔ). The effects of superimposing an Estes-Skinner procedure for delivering unavoidable shocks on all components of the multiple schedule were observed. The buzzer-shock pairing of the Estes-Skinner procedure produced an increased rate of responding on the avoidance component of the schedule and also on the SΔ components. No persistent change in rate was observed on the food component during the pre-shock stimulus. Control performances on all components could be regained by either extinguishing or eliminating the buzzer-shock pairing. Extinction of the avoidance responding had little effect on the increased rates of responding produced by the Estes-Skinner procedure on the SΔ and avoidance extinction components and did not lead to a conditioned suppression of the food reinforced responding. Rate of responding during the pre-shock stimulus was observed to be relatively independent of changes in the maintaining schedules. Responding during the pre-shock stimulus could be conditioned and maintained after an extensive history of avoidance extinction.  相似文献   
23.
Redundancy as a variable in pattern perception   总被引:1,自引:0,他引:1  
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25.
This study examines the factor structure of the Mobility Inventory for Agoraphobia and attempts to validate the inventory, using an Australian sample of agoraphobic patients, by comparison with other scales. One hundred twentyfour panic disorder with agoraphobia patients were studied. Factor analysis showed that a two-factor solution was the most suitable both when subjects were accompanied (accompanied condition) and when alone (alone condition). Factor I represented public, crowded, or social situations including department stores, supermarkets, restaurants, theaters, and panics and social gatherings. Factor II reflected enclosed or riding situations such as elevators, parking garages, enclosed spaces, and riding in subways or airplanes. These two factors accounted for 46.6% and 44.3% of the variance on the accompanied condition and the alone condition, respectively. The Mobility Inventory was significantly correlated with the Agoraphobia factor of the Fear Questionnaire and the Social Avoidance and Distress scale. These results indicated that the Mobility Inventory is a valid instrument to measure agoraphobic behavior.  相似文献   
26.
Three mildly malnourished children with cystic fibrosis and their parents participated in a behavioral group-treatment program that focused on promoting and maintaining increased calorie consumption. Treatment included nutritional education, gradually increasing calorie goals, contingency management, and relaxation training, and was evaluated in a multiple baseline design across four meals. Children's calorie intake increased across meals, and total calorie intake was 32% to 60% above baseline at posttreatment. Increased calorie consumption was maintained at the 96-week follow-up (2 years posttreatment). The children's growth rates in weight and height were greater during the 2 years following treatment than the year prior to treatment. Increases in pace of eating and calories consumed per minute were also observed 1 year posttreatment. These findings replicated and extended earlier research supporting the efficacy of behavioral intervention in the treatment of malnutrition in children with cystic fibrosis.  相似文献   
27.
I would like to thank Jonathan Lee, Terry Pinkard, Steven S. Schwarzschild, Jill Petzall, Bob Gibbs, Bill Hamrick and Jim Bohman for their very helpful criticisms of earlier drafts of this paper.  相似文献   
28.
Ratings during acute and follow-up care by 35 families having members with traumatic brain injury showed none of the medical facilities met families' needs though some aspects of patients' care were rated higher in hospitals. Findings suggest comprehensive surveys are needed.  相似文献   
29.
Given a normal (multi-)modal logic a characterization is given of the finitely presentable algebras A whose logics L A split the lattice of normal extensions of . This is a substantial generalization of Rautenberg [10] and [11] in which is assumed to be weakly transitive and A to be finite. We also obtain as a direct consequence a result by Blok [2] that for all cycle-free and finite A L A splits the lattice of normal extensions of K. Although we firmly believe it to be true, we have not been able to prove that if a logic splits the lattice of extensions of then is the logic of an algebra finitely presentable over ; in this respect our result remains partial.  相似文献   
30.
Kracht  Marcus  Wolter  Frank 《Studia Logica》1997,59(2):149-177
This papers gives a survey of recent results about simulations of one class of modal logics by another class and of the transfer of properties of modal logics under extensions of the underlying modal language. We discuss: the transfer from normal polymodal logics to their fusions, the transfer from normal modal logics to their extensions by adding the universal modality, and the transfer from normal monomodal logics to minimal tense extensions. Likewise, we discuss simulations of normal polymodal logics by normal monomodal logics, of nominals and the difference operator by normal operators, of monotonic monomodal logics by normal bimodal logics, of polyadic normal modal logics by polymodal normal modal logics, and of intuitionistic modal logics by normal bimodal logics.  相似文献   
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