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321.
Maximization and matching predictions were examined for a time-based analogue of the concurrent variable-interval variable-ratio schedule. One alternative was a variable interval whose time base operated relatively independent of the schedule chosen, and the other was a discontinuous variable interval for which timing progressed only when selected. Pigeons switched between schedules by pecking a changeover key. The maximization hypothesis predicts that subjects will show a bias toward the discontinuous variable interval and undermatching; however the obtained results conformed closely to the predictions of the matching law. Finally, a quantitative comparison was made of the bias and sensitivity estimates obtained in published concurrent variable-interval variable-ratio analogue studies. Results indicated that only the ratio-based analogue of the concurrent variable interval variable ratio studied by Green, Rachlin, and Hanson (1983) produced significant bias toward the variable-ratio alternative and undermatching, as predicted by reinforcement maximization.  相似文献   
322.
In two experiments, key pecking of pigeons was maintained by a variable-interval 180-s schedule of food presentation. Conjointly, a second schedule delivered response-dependent electric shock. In the first experiment, shocks were presented according to either a variable-interval or a nondifferential interval-percentile schedule. The variable-interval shock schedule differentially delivered shocks following long interresponse times. Although the nondifferential shock schedules delivered shocks less differentially with respect to interresponse times, the two shock schedules equally reduced the relative frequency of long interresponse times. The second experiment differentially shocked long or short interresponse times in different conditions, with resulting decreases in the relative frequency of the targeted interresponse times. These experiments highlight the importance of selecting the appropriate level of analysis for the interaction of behavior and environment. Orderly relations present at one level of analysis (e.g., interresponse times) may not be revealed at other levels of analysis (e.g., overall response rate).  相似文献   
323.
Nomothetic and idiographic content analytic approaches to the Rorschach are used in complementary fashion to explore the psychotic personality structure and primitive interpersonal models in a 37-year-old biologically normal male, who was a gynemimetic, that is, a transvestite who aspired to have the genetalia of a woman. The Rorschach was riddled with psychotic verbalizations and imagery suggesting inadequate differentiation from the original symbiosis, inadequate symbiosis anxiety, and significant separation anxiety--a constellation culminating in the transsexual fantasy of fusion with the mother.  相似文献   
324.
There is usually a long period of time between infection with the AIDS virus and manifestation of symptoms. Asymptomatic patients often would benefit from elective surgery for diseases such as arthritis which are unrelated to their infection. The surgeons' decisions to accept the risks to themselves, their spouses, and their operating teams in order to relieve pain and suffering appear to be based upon two covenants; one concerns their role within the doctor-patient relationship, and the other concerns their relationship to what they see as the ultimate meaning in life.  相似文献   
325.
In Phase 1 of this study, we asked 23 parents between the ages of 30 and 52 years and 26 children between the ages of 10 and 19 years to list effects of television and video games on children. A questionnaire was developed using the most frequently given responses (e.g., television influences children's aggressive behavior, verbal abilities, or time with friends). In Phase 2, this questionnaire was administered to different groups of parents and children and a control group of adults without offspring (N = 204) who were asked to rate the influence of each item on the questionnaire. Multivariate analyses of variance indicated that there were similarities and differences among the groups. For example, parents and other adults held similar beliefs about the influence of television, but parents held more positive beliefs about the influence of video games than the other adults. Children held more positive beliefs about the influence of television than parents, but parents and children held similar beliefs about the influence of video games.  相似文献   
326.
In the first experiment, 4 pigeons were each presented with a recurring sequence of four key colors followed by the delivery of grain (block clock). Once the rate of pecking had stabilized, three of the colors were replaced, during different series of sessions, by a darkening of the key. The rate of pecking was reduced within those segments of the interval between deliveries of food during which the key was dark; when the key was dark during the final portion of the interval, rates were reduced throughout the entire interval. In the second experiment, 3 new pigeons were exposed to a different sequence of colors, and the final stimulus was replaced in successive conditions by a novel color, a darkened key, and a restoration of the original color. The data indicated that darkening the key had a more severe, more extensive, and more persistent effect than did a mere change in color. These results suggest that it may be fruitful to conceptualize the autoshaping procedure as a special version of the block clock in which pecking is suppressed throughout the greater part of the interval by darkening the key. In the final condition, the same stimulus appeared in each of the last three portions of the interval. The rate of pecking was lower during the last two portions than when distinctive colors were presented, with the peak rate now appearing in the fifth of seven equal temporal components.  相似文献   
327.
In Part 1 of this paper, topics germane to the projective assessment of autobiographical memory were discussed. In Part 2, the cognitive-perceptual method will be used to interpret several early memories and a slightly abridged Early Memories Procedure (EMP).  相似文献   
328.
177 respondents attending a midwestern state university reported greater alienation from the wider society when they held more positive attitudes than negative ones toward women and homosexuals. Alienation and attitudes toward African-Americans, women, and homosexuals were not influenced by gender or religiosity.  相似文献   
329.
A capacity theory of comprehension: individual differences in working memory.   总被引:77,自引:0,他引:77  
A theory of the way working memory capacity constrains comprehension is proposed. The theory proposes that both processing and storage are mediated by activation and that the total amount of activation available in working memory varies among individuals. Individual differences in working memory capacity for language can account for qualitative and quantitative differences among college-age adults in several aspects of language comprehension. One aspect is syntactic modularity: The larger capacity of some individuals permits interaction among syntactic and pragmatic information, so that their syntactic processes are not informationally encapsulated. Another aspect is syntactic ambiguity: The larger capacity of some individuals permits them to maintain multiple interpretations. The theory is instantiated as a production system model in which the amount of activation available to the model affects how it adapts to the transient computational and storage demands that occur in comprehension.  相似文献   
330.
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