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81.
The simultaneous effects of the sex-role appropriateness of the task and the presence or absence of competition upon the attributions made by males and females were studied with 192 college students. Contrary to predictions, males rated themselves as luckier than females in the competitive conditions. However, as predicted, females made fewer self-serving attributions for the male than the female task.  相似文献   
82.
Adoption of a child is an event in which a number of crises have converged. Both the biologic and adoptive families have contributed their failures and crises, and the subsequent interpretations of these by the adopted child can lead to polarized themes of goodness and badness. The absence of the biologic parents and of a coherent history reinforces the tendency to splitting. This paper explores these operations and raises questions about prevailing adoption practices.Paper presented at Spence-Chapin Symposium on Identity Problems of Children in Non-Nuclear Families, April 11, 1981.  相似文献   
83.
Six pigeons were trained to discriminate different light intensities in four experimental procedures. Experiment 1 compared stimulus discriminability in a yes-no signal-detection task with discriminability measures obtained from two free-operant procedures. Discriminability estimates were significantly lower in the detection procedure. Experiment 2 showed this lowered discriminability to be a function of the delay between stimulus presentation and the availability of the choice-response keys in the standard detection task. In addition, reinforcement sensitivity was lowest when correct choice responses were intermittently, rather than continuously, reinforced.  相似文献   
84.
This study evaluated the effectiveness of the Primary Mental Project (PMHP), a program for early detection and prevention of school adjustment problems. Pre- and postprogram assessments were done with 215 primary-grade children seen in PMHP, usig teacher ratings of problem behaviors and competencies, and child-aide ratings of problems. School mental health professionals judged educational and behavioral changes in project children during the year. Significant across-the board improvements were found on all criterion measures. Modest intercorrelations among criterion change estimates suggested that the observed changes were due to program, rather than halo, effects. PMHP children also improved significantly more than matched, retrospective controls.  相似文献   
85.
A microprocessor system can be used both to control aversive conditioning (classical, signaled and Sidman avoidance, and conflict) experiments and to acquire behavioral data in multiple subjects at a fraction of the cost of solid state systems. The software described in this paper can be used to program tones and shocks and count responses, independently, in up to 12 animals simultaneously.  相似文献   
86.
87.
The language development of three 9- and 10-year-old children possessing only a right or a left hemisphere was studied. Surgical removal of one brain half antedated the beginning of speech, so each child has acquired speech and language with only one hemisphere. Different configurations of language skill have developed in the two isolated hemispheres: phonemic and semantic abilities are similarly developed but syntactic competence has been asymmetrically acquired. In relation to the left, the right brain half is deficient in understanding auditory language, especially when meaning is conveyed by syntactic diversity; detecting and correcting errors of surface syntactic structure; repeating stylistically permuted sentences; producing tag questions which match the grammatical features of a heard statement; determining sentence implication; integrating semantic and syntactic information to replace missing pronouns; and performing judgments of word interrelationships in sentences. Language development in an isolated right hemisphere, even under seizure-free conditions, results in incomplete language acquisition.  相似文献   
88.
89.
Genetically informative samples can address hereditary and experiential influences on suicide‐related behaviors. The frequency of suicide‐related behaviors was compared in twins from two survivor groups: (1) those whose co‐twins' deaths were suicides (monozygotic [MZ]: n = 47; dizygotic [DZ]: n = 31), and (2) those whose co‐twins' deaths were nonsuicides (MZ: n = 347; DZ: n = 170). The frequency of suicide attempts among suicide survivors was significantly higher in MZ than DZ twins, while the frequency of suicide attempts among nonsuicide twin survivors did not differ between MZ and DZ twins. Twin concordance for suicide attempts more likely reflects a genetic predisposition than a behavioral reaction to the loss.  相似文献   
90.
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