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301.
This study compared Piagetian cognitive development in normal achieving children and two groups of children with learning disabilities designated as either auditory-linguistic or visual-spatial on the basis of Verbal-Performance IQ differences on the Wechsler Intelligence Scale for Children-Revised (WISC-R; 1974). The two groups with learning disabilities were matched with normal achieving controls on intelligence, socioeconomic status, sex, race, and age. Piagetian tasks measuring conservation, seriation, and classification were administered to each child to determine level of operative thought. The auditory-linguistic group scored significantly below normal controls in operativity, and significantly fewer were at a concrete operational level on a conservation of length task than were normal achieving children. The visual-spatial group did not differ significantly from normal controls. These results suggest that auditory-linguistic disabilities may be more detrimental than visual-spatial disabilities to development of operativity. 相似文献
302.
We demonstrated the efficacy of using early memory (EM) data to distinguish postdictively criminally dangerous from nondangerous psychiatric patients. Dangerous patients (n = 30) had been adjudicated not criminally responsible (NCR) for felonies, whereas nondangerous psychiatric patients (n = 30) had no convictions for aggressive offenses. Groups were comparable in age, IQ, socioeconomic status (SES), marital status, and diagnoses. Group racial compositions, however, were significantly different. Statistical analyses were thus performed to clarify the potential effect of this racial confound. Overall, 73% of the dangerous and nondangerous patients were accurately classified via a newly developed EM scoring system, the Early Memory Aggressiveness Potential Score System (EMAPSS). Of those classified as dangerous, 15 of 16 (94%) were actually dangerous. The false-positive rate was an impressively low 6%, suggesting EM aggression is highly predictive of dangerousness postdictively. 相似文献
303.
304.
The effectiveness of AIDS education may depend on the development of models that predict and explain HIV prevention behavior. In this study, the aim was to test Fishbein and Ajzen's theory of reasoned action model in predicting women's capacity to tell their partner to use condoms. The basic theory pertains to the relationship of 1) attitude toward behavior and 2) the subjective norms to behavior; further refinements reflect factors such as 3) perceived behavioral control or self-efficacy, 4) and perceived barriers. A sample was drawn of 123 female first-year teacher trainees in Harare, Zimbabwe, in late 1990; a self-administered questionnaire was distributed and returned. 72% of the respondents were sexually experienced. The mean age of the entire sample was 24 years. The results of the multiple linear regression indicated that the model was able to predict were F(2,74)=32.81, p.0001. 47% of the variance was explained by this Fishbein model. Attitude toward behavior was significantly associated with the intention to tell one's partner to use condoms (beta = .60, p .05). Subjective norms were not significant (beta = .15, p .05). Perceived behavioral control and perceived barriers were also not significantly associated with the intention to tell one's partner to use condoms. A caveat was that the subjective norm was measured by only one item, and an improved conceptualization and measurement of this construct might have changed the relationship. The suggestion is that health educators should address women's underlying beliefs and attitudes about the benefits of telling their partners to use condoms. Future prospective studies will better delineate the relationship between attitude and behavior. 相似文献
305.
Choice with delayed and probabilistic reinforcers: effects of variability, time between trials, and conditioned reinforcers.
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In a discrete-trials procedure with pigeons, a response on a green key led to a 4-s delay (during which green houselights were lit) and then a reinforcer might or might not be delivered. A response on a red key led to a delay of adjustable duration (during which red houselights were lit) and then a certain reinforcer. The delay was adjusted so as to estimate an indifference point--a duration for which the two alternatives were equally preferred. Once the green key was chosen, a subject had to continue to respond on the green key until a reinforcer was delivered. Each response on the green key, plus the 4-s delay that followed every response, was called one "link" of the green-key schedule. Subjects showed much greater preference for the green key when the number of links before reinforcement was variable (averaging four) than when it was fixed (always exactly four). These findings are consistent with the view that probabilistic reinforcers are analogous to reinforcers delivered after variable delays. When successive links were separated by 4-s or 8-s "interlink intervals" with white houselights, preference for the probabilistic alternative decreased somewhat for 2 subjects but was unaffected for the other 2 subjects. When the interlink intervals had the same green houselights that were present during the 4-s delays, preference for the green key decreased substantially for all subjects. These results provided mixed support for the view that preference for a probabilistic reinforcer is inversely related to the duration of conditioned reinforcers that precede the delivery of food. 相似文献
306.
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
307.
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
308.
C A Peterson 《Journal of personality assessment》1992,58(3):464-479
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
309.
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
310.
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