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171.
Pigeons were trained to discriminate 5 mg/kg pentobarbital from saline under concurrent variable-ratio (VR) VR schedules, in which responses on the pentobarbital-biased lever were reinforced under the VR schedule with the smaller response requirements when pentobarbital was given before the session, and responses on the saline-biased key were reinforced under the VR schedule with the larger response requirements. When saline was administered before the session, the reinforcement contingencies associated with the two response keys were reversed. When responding stabilized under concurrent VR 20 VR 30, concurrent VR 10 VR 40, or concurrent VR 5 VR 50 schedules, pigeons responded almost exclusively on the key on which fewer responses were required to produce the reinforcer. When other doses of pentobarbital and other drugs were substituted for the training dose, low doses of all drugs produced responding on the saline-biased key. Higher doses of pentobarbital and chlordiazepoxide produced responding only on the pentobarbital-biased key, whereas higher doses of ethanol and phencyclidine produced responding only on this key less often. d-Amphetamine produced responding primarily on the saline-biased key. When drugs generalized to pentobarbital, the shape of the generalization curve under concurrent VR VR schedules was more often graded than quantal in shape. Thus, drug discrimination can be established under concurrent VR VR schedules, but the shapes of drug-discrimination dose-response curves under concurrent VR VR schedules more closely resemble those seen under interval schedules than those seen under fixed-ratio schedules. Graded dose-response curves under concurrent VR VR schedules may relate to probability matching and difficulty in discriminating differences in reinforcement frequency. 相似文献
172.
The formation of a generalized categorization repertoire: effect of training with multiple domains,samples, and comparisons
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Fields L Reeve KF Matneja P Varelas A Belanich J Fitzer A Shamoun K 《Journal of the experimental analysis of behavior》2002,78(3):291-313
The present experiment explored the effects of three variables on the spontaneous categorization of stimuli in perceptually distinct and novel domains. Each of six stimulus domains was created by morphing two images that were the domain endpoints. The endpoints of the domains were male and female faces, two abstract drawings, a car and a truck, two banded-elevation satellite land images, a tree and a cat, and two false-color satellite images. The stimulus variants at each end of a domain defined two potential perceptual classes. Training was conducted in a matching-to-sample format and used stimuli from one or two domains, one or three variants per class as samples, and one or three variants per class as comparisons. The spontaneous categorization of stimuli in the untrained stimulus domains showed the emergence of a generalized categorization repertoire. The proportion of spontaneously categorized stimuli in the new domains was positively related to the number of domains and samples used in training, and was inversely related to the number of comparisons used in training. Differential reaction times demonstrated the discriminability of the stimuli in the emergent classes. This study is among the first to provide an empirical basis for a behavior-analytic model of the development of generalized categorization repertoires in natural settings. 相似文献
173.
Experiments have shown that human and nonhuman subjects are capable of performing new arbitrary stimulus-stimulus relations without error. When subjects that are experienced with matching-to-sample procedures are presented with a novel sample, a novel comparison, and a familiar comparison, most respond by correctly selecting the novel comparison in the presence of the new sample. This exclusion paradigm was expanded with two California sea lions that had previously formed two 10-member equivalence classes in a matching-to-sample procedure. Rather than being presented with a novel sample on a given trial, the sea lions were presented with a randomly selected familiar member of one class as the sample. One of the comparisons was a randomly selected familiar member of the alternative class, and the other was a novel stimulus. When required to choose which comparison matched the sample, the subjects reliably rejected the familiar comparison, and instead selected the unfamiliar one. Next, the sea lions were presented with transfer problems that could not be solved by exclusion; they immediately grouped the new stimuli into the appropriate classes. These findings show that exclusion procedures can rapidly generate new stimulus relations that can be used to expand stimulus classes. 相似文献
174.
Bertram D. Cohen 《Group》2002,26(3):189-204
The group self, an individual's self-perception as a member of a group, is distinguished from the group's self, a personification of the group as a person with a self. The perceived group's self of an opposing other group is often a repository for attributes group members are not ready to recognize in their own group's self. Theoretically, the need for an adversarial other to hold one's own group's unwanted attributes—and thus to complete one's own group's self—contributes, however unconsciously, to the apparent intractability of intergroup disputes. In dealing with these issues, I compare intergroup conflict resolution (ICR) groups with therapy groups, on the one hand, and advocacy groups on the other. All of this sets the stage for a presentation of two ICR projects and their analysis in group-developmental terms. 相似文献
175.
The Dental Subscale of the Children's Fear Survey Schedule: Predictive Value and Clinical Usefulness
M. Ten Berge J. S. J. Veerkamp J. Hoogstraten P. J. M. Prins 《Journal of psychopathology and behavioral assessment》2002,24(2):115-118
This study reports on the predictive value and clinical usefulness of the Dutch parental version of the Dental Subscale of the Children's Fear Survey Schedule (CFSS-DS). Parents of 718 children (4–12 years) completed this CFSS-DS version before or during the child's visit. The dentist rated the child's dental fear during treatment on a 5-point Likert-type Scale from 1 (not afraid at all) to 5 (very afraid). Reliability analysis was performed, and correlation coefficients between the two measures were calculated. The reliability of the scale proved to be high (Cronbach's = .93) and significant correlation coefficients were found (r = .58 and r = .68, p < .01). The negative predictive value of the CFSS-DS was high (.96), whereas its positive predictive value was relatively low (0.41). It was concluded that the CFSS-DS might be of clinical value as a screening device of dental fear, whereas its predictive value of fearful behavior should not be overestimated. 相似文献
176.
Amir Cohen-Shalev 《Journal of Aging and Identity》2002,7(1):17-23
The film She's Been Away tells the story of an old woman who had been locked in a mental asylum while a teenager, for willfully violating repressive sexual codes. Sixty years later her ward is closed and she moves in with her nephew and his wife. Faced with what appears to be a hopeless situation, she manages to forge a sense of a meaningful closure to a misspent life. Through narrative, story structure, and characterization the film throws into focus coping mechanisms and ego strategies deployed by a triple disadvantaged person (woman, old, and mad) in her ascent to a reconstructed selfhood. As the protagonist ties both ends of her life, and faces the abyss in between she makes genuine adaptive use of so-called regressive, late-life development assets (available to a lesser degree to elderly people in normal life circumstances), primarily the abolition of linear time. Through this abolition she makes reminiscing an actual reality while still maintaining a functional separation between the real and the remembered. Her portrayal is a valuable document for gerontologists as it explores, through artistic imagination and intuition, the workings of an aging mind in search for a meaningful sense of closure. 相似文献
177.
178.
Early Developmental Precursors of Externalizing Behavior in Middle Childhood and Adolescence 总被引:1,自引:0,他引:1
This study examined the infancy- and toddler-age precursors of children's later externalizing problem behavior. Risk constructs included suboptimal patterns of observed caregiver-child interaction and the caregiver's perception of child difficultness and resistance to control. In addition, a novel dimension of caregiver-child relationship quality, the caregiver's perception of her toddler's unresponsiveness to her, was examined as a possible precursor of children's externalizing behavior. Externalizing problem outcomes were assessed throughout the school-age period and again at age 17, using multiple informants. As toddlers, children at risk for later externalizing behavior were perceived as difficult and resistant to control, and relationships with their caregivers were relatively low in warmth and affective enjoyment. Finally, the caregiver's perception of her toddler as emotionally unresponsive to her was a consistent predictor of later externalizing behavior, suggesting that negative maternal cognitions associated with child conduct problems may begin in toddlerhood. These predictive patterns were similar for boys and girls, and with minor exceptions, generalized across different subdimensions of externalizing problem behavior. Our findings underscore the importance of the infancy and toddler periods to children's long-term behavioral adjustment, and indicate the desirability of further research into the nature of caregivers' early perceptions of child unresponsiveness. 相似文献
179.
Maglieri KA DeLeon IG Rodriguez-Catter V Sevin BM 《Journal of applied behavior analysis》2000,33(4):615-618
Covert food stealing is common among individuals with Prader-Willi syndrome. We found that verbal reprimands, delivered contingent upon eating prohibited foods, were sufficient to decrease the food stealing of a girl with Prader-Willi syndrome. Warning stimuli were then used to help her discriminate between permitted and prohibited foods during sessions in which food stealing was not directly observed. This procedure resulted in decreases in food stealing from containers labeled with the warning stimuli. 相似文献
180.
Children with attention deficit hyperactivity disorder (ADHD) are often treated with central nervous system stimulants, making the evaluation of medication effects an important topic for applied behavior analysts. Because assessment protocols emphasize informant reports and direct observations of child behavior, little is known about the extent to which children themselves can accurately report medication effects. Double-blind placebo-controlled procedures were used to examine whether 6 children with ADHD could recognize the effects of their medication. The children were given math worksheets to complete for 15 min during each of 14 sessions while on medication and placebo. Children completed a self-evaluation form at the end of each session, and ratings were compared to observed behavior and academic performance. Results indicated that 3 children were able to accurately report their medication status at levels greater than chance, whereas the accuracy of reports by all children was related to dosage level, differences in behavior, and the presence of adverse effects. The implications of these results for placebo-controlled research, self-monitoring of dosage levels, and accuracy training are discussed. 相似文献