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11.
Two experiments were designed to assess whether depriving rats of food would increase the reinforcement effectiveness of wheel running (Experiment 1) and whether satiation for wheel running would decrease the reinforcement effectiveness of food (Experiment 2). In Experiment 1, a progressive-ratio schedule was used to measure the reinforcement effectiveness of wheel running when rats were deprived or not deprived of food. Completion of a fixed number of lever presses released a brake on a running wheel for 60 s, and the response requirement was systematically increased until the rat stopped pressing or until 8 hr had elapsed. The ratio value reached (and the total number of lever presses) was an inverted-U function of food deprivation (percentage body weight). In Experiment 2, when wheel running preceded test sessions, fewer food-reinforced lever presses were maintained by the progressive-ratio schedule, and responding occurred at a lower rate on a variable-interval schedule. An interpretation of these results is that deprivation or satiation with respect to one event (such as food) alters the reinforcement effectiveness of a different event (such as access to wheel running).  相似文献   
12.
Thirty-two children designated as hyperactive (ADD) were compared with an equal number of control subjects who were matched for age, sex, and verbal IQ. The subjects were tested on (1) a component selection task, measuring serial memory and incidental learning and (2) a cancellation task, assessing attentional variables and distractibility. No straightforward group differences were found on the component selection task, whereas hyperactive subjects made more omission and commission errors than controls on the cancellation task. It was concluded that a deficit in sustained attention and impulsivity best described the group differences. Age was also found to influence performance on a number of variables, including incidental learning on the component selection task and response rate and omission errors on the cancellation task. Because subjects in the hyperactive group were rated as extreme on a number of subscales not necessarily related to hyperactivity, the data were reexamined by multiple regression analyses. Subscales considered to be related both to hyperactivity and to conduct disorder were associated with different performance variables, indicating that each of these subscales provided some unique information.This study was supported by a grant from the Medical Research Council of New Zeland to the first author. The authors would like to thank the pupils and staff of Mt. Eden Normal Primary School and Newmarket School for taking part in the study, and the Auckland Education Board for granting approval for the study. We also thank Prof. J. S. Werry, Dr. J. Reeves, and Mrs. G. Elkind for assistance in locating some of the control subjects. Special thanks goes to Gail Elkind for assistance with the statistical analysis.  相似文献   
13.
This research examined the relationship between body size and mass and the performance of 3- to 6-year-old children (n=117) on two categories of swimming tasks: Locomotion: Front and Locomotion: Back. The major hypothesis was that body size and mass measurements would be good predictors of children's swimming performance. The function of age/gender also was examined. Stepwise multiple regression was used to select the best predictors of swimming performance after controlling for amount of aquatic training and child's apprehensiveness about water. Body weight was the best predictor of children's swimming performance on each category of tasks (p<0.01). It accounted for at least 16% of performance variation when entered alone, and it accounted for 5% given age. Age was of little importance after body size and mass were taken into account. The major conclusion was that future research should incorporate more complex research designs to account for the network of influencing factors.  相似文献   
14.
Sarah Brabant  Linda Mooney 《Sex roles》1986,14(3-4):141-148
The present research replicates Brabant's (Sex role stereotyping in the Sunday comics. Sex Roles, 1976, 2(4), 331–337) analysis of sex role stereotyping in family-oriented Sunday comics. Cartoons were collected for the same six-month period and compared to the 1974 data. Females continue to appear less frequently and to remain in the home more often than males. They also continue to be protrayed in stereotypical roles.  相似文献   
15.
This study assessed 13 aphasic subjects' knowledge of the multiple meanings of homographs. The results indicated that the various meanings were less available to aphasic subjects than to normal subjects. In addition, specific meanings became less available as they became less typical although the number of meanings associated with a homograph did not influence performance. Aphasia type also did not influence performance. Performance on the experimental test was significantly correlated with auditory comprehension level and picture naming ability. The results were related to recent findings on semantic organization in aphasia.  相似文献   
16.
A technique comparing first-person singular and first-person plural address modes (based on the Tennessee Self-concept Scale and modifications) was applied. Self-report and sociometric-like techniques were blended into a single method, providing a compound profile of the individual's interaction with his small, cohesive reference group. One hundred and sixteen males aged 18–22 yr participated in this study. The results vary significantly in accordance with the characteristics of the subgroup, and follow trends that may be seen as confirming the rules governing the interpretation of the profile. A set of rules is evolved (in the Discussion) by which the profile can be interpreted. The results distinguish significantly between people with marked leadership and instructional skills, and provide significant correlations with sociometric data concerning leadership propensities. The present technique suggests possible further elaborations for clinical diagnostic purposes and for assessment in personal and social psychological settings.  相似文献   
17.
Elpern  Sarah  Karp  Stephen A. 《Sex roles》1984,10(11-12):987-992
Sex Roles - The incidence of depressive disorders among women in our society is considerably higher than it is for men. Several investigators have suggested that this is due to traditional sex...  相似文献   
18.
In the literature on cotherapy, little attention has been focused on maximizing the effectiveness of two therapists working in tandem with families and couples. While cotherapists may at times share their ideas and feelings with their clients, and after the therapeutic session exchange views between themselves, generally little interaction occurs between them during the session. In this paper, a case is presented for more active interactions between cotherapists during the session, in order to expedite and facilitate change and growth in their clients. Anecdotal examples are provided to illustrate the approach.  相似文献   
19.
African Americans are at significantly greater risk of hypertension and worse cardiovascular outcomes than other racialized groups, yet hypertension intervention effects remain limited. Thus, it is necessary to understand the potential mechanisms whereby interventions may be more effectively targeted to improve health. Supported by prior research evidence and guided by the Biobehavioral Family Model, this study examined associations between family relationship quality, psychological wellbeing, and self-management behaviors for African Americans with hypertension. Data were pooled from three Midlife Development in the U.S. projects, resulting in a sample of 317 African Americans (63.4% female, Mage = 53.32) with self-reported high blood pressure in the past 12 months. We tested four cross-sectional multiple mediator models, with depressed mood and environmental mastery mediating associations between family strain and exercise, smoking, problematic alcohol use, and stress-eating. Environmental mastery mediated the association between greater family strain and decreased odds of achieving recommended exercise levels; greater odds of reporting problematic alcohol use; and greater stress-eating. Though family strain was associated with depressed mood in each model, this variable did not serve as an indirect pathway to self-management behaviors. Family strain, and the potential pathway identified via environmental mastery, may be a meaningful predictor of disease self-management for African Americans with hypertension. Longitudinal studies are needed to examine directionality and to support intervention trials for improving self-management and hypertension outcomes.  相似文献   
20.
Research shows that parents have a strong influence on the party preferences of their children. Yet little is known about how such preferences are transmitted in multiparty systems with weak party identification and high electoral volatility. We propose a model of intergenerational transmission that includes both direct effects of parents' party preferences on those of their children, as well as indirect effects through left–right and issue positions. We test this model with original survey data of Dutch adolescents (14–20 years old) and their parents (N = 751 adolescent-parent pairs). We find two paths through which parents exert influence on the party preferences of their adolescent children. On the first path, parental party preferences function as a direct predictor of adolescent party preferences. On the second path, adolescent left–right and issue positions function as a mediator between parental left–right and issue positions and adolescent party preferences, with the effect of left–right positions being stronger than that of issue positions. The frequency with which adolescents discuss political topics with their parents moderates these effects.  相似文献   
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