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861.
This research examined the effects of structural complexity and sex of stepchild on the quality of stepfather-stepchild relationships. Sixteen simple stepfather families (the wife had custody of a child from a previous marriage, but the stepfather has no biological children) and 16 complex stepfather families (the wife had custody of a child from a previous marriage, and the stepfather was a noncustodial biological parent) with half of each type (N = 8) having a male and half having a female, 9-12-year-old target child participated in a multimethod-multimeasure assessment of the stepfather-stepchild relationship. Families were recruited from marriage license records, and data collection was accomplished in a single three-and-a-half-hour home visit. Dependent variables included: (a) questionnaire measures of love and detachment relationship dimensions independently obtained from parents, stepparents, and (step)children, and (b) proportions of positive and negative stepparent and stepchild communication behaviors derived from videotaped interaction tasks. Findings revealed that simple and complex stepfather families did not differ on any questionnaire or behavioral measures. Girls, however, engaged in a lower proportion of positive verbal and greater proportion of negative problem-solving behaviors toward their stepfathers than boys did. Stepfathers did not differ on proportions of communication behaviors emitted toward boys and girls. No sex-of-child differences were obtained on the questionnaire measures. Directions for future research on structural complexity and stepfather families are discussed.  相似文献   
862.
This paper addresses the controversy in family therapy over basic philosophical issues in terms of a historical opposition between demonstrative and dialectical metatheories. It argues that advances in family therapy are indicative of the growing prominence of dialectical forms of understanding in the social sciences. Several family therapy concepts are explored as representative of the dialectical categories of motion, form, relationship, and transformation.  相似文献   
863.
864.
865.
Effects of new types of reinforcement, alien type and alien combined with external type (double reinforcement), were examined in comparison with a conventional external one. One hundred and twenty children, 6th grade boys and girls, worked on learning discrimination tasks. Under alien reinforcement, upon correct responses of the child the experimenter received reinforcers from him-(or her-) self thus reinforcing the child responses. Under each condition, alien, external or double, children learned the tasks and their learning efficacy increased. Personality characteristics of children, in terms of extraversion and emotionality, differentiated effects of three reinforcement conditions on learning behavior and efficacy. The effect of alien reinforcement was influenced by the personality factors most, and that of double reinforcement least. In addition, personality factors influenced differently between alien and external conditions. Learning occurred differently under three different conditions of reinforcement, depending on the personality type of learners. Underlying mechanisms of alien reinforcement were different from, and its functions were independent of, those of external reinforcement. None of the effects of alien reinforcement on learning and motivation were contaminated by the intellectual faculties of learners.  相似文献   
866.
We investigated the programming of generalization and maintenance of correspondence between verbal and nonverbal behavior in a preschool setting. Four children participated in a series of multiple-baseline designs. In Experiment 1, delayed reinforcement of verbal behavior effectively controlled maintenance of correspondence with previously trained responses and also resulted in generalization of correspondence to one untrained response. As the latter effect was limited, Experiment 2 was a further assessment of the effects of delayed reinforcement of generalization of correspondence to untrained responses, and consistent generalization was shown. Experiment 2 also showed that generalization, if lost, could be recovered through use of "booster training," in which the original contingencies were reinstated for a brief period. Experiment 3 provided replications, with two additional children, of the effects of delayed reinforcement on maintenance of correspondence. Results are discussed in terms of using delayed reinforcement as an indiscriminable contingency.  相似文献   
867.
868.
The effect of informational feedback on the protein and caloric consumption of burn patients was investigated using a multiple-baseline across subjects. The patients were four severely burned adult males who failed to consume sufficient foods to achieve prescribed levels of protein or kilocalories via standard burn unit procedures during recovery. Feedback consisted of informing patients of (a) their prescribed levels of protein and kilocalories, (b) the protein and kilocalorie content of hospital foods and beverages, and (c) their actual intake of protein and kilocalories. Following the provision of feedback, there was an increase in protein and kilocalorie intakes and in the number of days during which prescribed levels for protein and kilocalories were achieved. These results suggest that the informational feedback was effective for improving the oral caloric intake of burn patients.  相似文献   
869.
Two experiments assessed infant sensitivity to figural coherence in point-light displays moving as if attached to the major joints of a walking person. Experiment 1 tested whether 3- and 5-month-old infants could discriminate between upright and inverted versions of the walker in both moving and static displays. Using an infant-control habituation paradigm, it was found that both ages discriminated the moving but not the static displays. Experiment 2 was designed to clarify whether or not structural invariants were extracted from these displays. The results revealed that (1) moving point-light displays with equivalent motions but different topographic relations were discriminated while (2) static versions were not, and (3) arrays that varied in the amount of motion present in different portions of the display were also not discriminated. These results are interpreted as indicating that young infants are sensitive to figural coherence in displays of biomechanical motion.  相似文献   
870.
Five-year-old children were tested for perceptual trading relations between a temporal cue (silence duration) and a spectral cue (F1 onset frequency) for the “say-stay” distinction. Identification functions were obtained for two synthetic “say-stay” continua, each containing systematic variations in the amount of silence following the /s/ noise. In one continuum, the vocalic portion had a lower F1 onset than in the other continuum. Children showed a smaller trading relation than has been found with adults. They did not differ from adults, however, in their perception of an “ay-day” continuum formed by varying F1 onset frequency only. The results of a discrimination task in which the two acoustic cues were made to “cooperate” or “conflict” phonetically supported the notion of perceptual equivalence of the temporal and spectral cues along a single phonetic dimension. The results indicate that young children, like adults, perceptually integrate multiple cues to a speech contrast in a phonetically relevant manner, but that they may not give the same perceptual weights to the various cues as do adults.  相似文献   
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