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131.
Time-use diaries were collected over a 3-year period for 2 cohorts of 2- and 4-year-old children. TV viewing declined with age. Time spent in reading and educational activities increased with age on weekdays but declined on weekends. Time-use patterns were sex-stereotyped, and sex differences increased with age. As individuals' time in educational activities, social interaction, and video games increased, their time watching entertainment TV declined, but time spent playing covaried positively with entertainment TV. Educational TV viewing was not related to time spent in non-TV activities. Maternal education and home environment quality predicted frequent viewing of educational TV programs and infrequent viewing of entertainment TV. The results do not support a simple displacement hypothesis; the relations of TV viewing to other activities depend on the program content, the nature of the competing activity, and the environmental context.  相似文献   
132.
We investigated the psychological impact of an organized visit to Polish concentration camps on Jewish-American adolescents. Eighty-seven adolescents who participated in a B'nai B'rith memorial visit to concentration camps in Poland completed measures of general psychological adjustment and posttraumatic stress disorder (PTSD) at four time-points: pretest, posttest, 6-month follow-up and 12-month follow-up. Measures included the SCL-90-R, the Mississippi Scale for PTSD, and the Impact of Events Scale (IES) for PTSD. On the SCL-90-R, changes in somatization, interpersonal sensitivity, obsessive-compulsive tendencies, depression, anxiety, and phobic anxiety were observed over time, with peak symptom scores at posttest and 6-month follow-up. Scores on the Mississippi Scale for PTSD and the IES Intrusion subscale also increased at 6-months. Predictors of PTSD symptoms on the Mississippi Scale included previous psychiatric treatment and SCL-90-R symptoms of paranoia, depression, and psychosis. Elevated psychotic symptoms on the SCL-90-R predicted PTSD symptoms on the IES. Jewish adolescents with preexisting symptoms of generalized distress or psychoticism appeared at increased risk for PTSD symptoms following exposure to Holocaust stimuli. This study contributes a prospective, multi-measure assessment of trauma reactions in adolescents.  相似文献   
133.
African American and White mother/adolescent pairs were examined for familial associations in body size and weight concerns. Mothers' and adolescents' estimates of adolescents' body mass index (BMI) were significantly correlated. Compared to boys, girls had greater body dissatisfaction, higher weight concerns, and perceived higher family/friend weight concerns. By race, White adolescents had more body dissatisfaction and greater concern about weight than African American adolescents. Four items explained 70.4% of the variance in adolescents' weight concern scores: adolescents' weight management practices, mothers' reports of adolescents' saying they were too fat, adolescents' perceptions of family/friends' weight concerns, and adolescents' body dissatisfaction. Our study suggests White girls are more concerned about their weight and perceive greater weight and dieting concerns among family/friends than African American girls.  相似文献   
134.
Depression is a serious problem among older adults and there is limited research on the most effective way to implement and evaluate the effects of expressive touch, either alone or in combination with verbalization, on levels of depression. A convenience sample of 24 institutionalized depressed older adult subjects (15 females and 9 males), ages 67 to 91 years was used for this study. An interrupted time series with multiple replications design was employed with four measurements: Geriatric Depression Scale (GDS), Life-Satisfaction-A-Scale, Rosenburg Self-Esteem Scale, and Locus of Control Scale. Four interventions were implemented: expressive touch only, verbalization only, a combination of expressive touch and verbalization, and a control (presence). Significant differences were found between pretest and posttest scores on the GDS for the expressive touch/verbal intervention. The most comfortable locations to implement the expressive touch and combination interventions were in the dining room or at the subject's bedside. The most comfortable areas of the subjects' bodies touched were the arms, hands, shoulders, and back. Results of this study support an important link between depression, self-esteem, locus of control, and life satisfaction and expressive touch either alone or when combined with talk. Touch as a mode of effective social support may have a therapeutic effect for depressed older adults.  相似文献   
135.
Conduct Disorder in Girls: A Review of the Literature   总被引:8,自引:0,他引:8  
The study of Conduct Disorder (CD) has primarily been limited to boys. The lack of research resulted from a premise that CD in girls was rare. However, CD in girls is a relatively common psychiatric diagnosis, and appears to be associated with several serious outcomes, such as Antisocial Personality Disorder and early pregnancy. Understanding gender differences in the course and severity of CD may lead to important information about etiology. Empirical studies on precursors, developmental course, risk factors and treatment for CD in girls are reviewed, while highlighting similarities and differences between girls and boys. Generally, CD symptoms in girls are stable. Precursors to CD in girls probably include Oppositional Defiant Disorder and temperamental factors, but also may include certain negative cognitions. What distinguishes CD in girls is the high risk they have to develop comorbid conditions, especially internalizing disorders. Risk factors for CD in girls partly overlap with those known for boys, but some factors appear to be highly salient for girls. Finally, there may be some significant effects of gender on treatment efficacy. Implications of these findings for future etiologic research are discussed.  相似文献   
136.
Experiments designed to establish stimulus equivalence classes frequently produce differential outcomes that may be attributable to training structure, defined as the order and arrangement of baseline conditional discrimination training trials. Several possible explanations for these differences have been suggested. Here we develop a hypothesis based on an analysis of the simple simultaneous and successive discriminations embedded in conditional discrimination training and testing within each of the training structures that are typically used in stimulus equivalence experiments. Our analysis shows that only the comparison-as-node (many-to-one) structure presents all the simple discriminations in training that are subsequently required for consistently positive outcomes on all tests for the properties of equivalence. The sample-as-node (one-to-many) training structure does not present all the simple discriminations required for positive outcomes on either the symmetry or combined transitivity and symmetry (equivalence) tests. The linear-series training structure presents all the simple discriminations required for consistently positive outcomes on tests for symmetry, but not for symmetry and transitivity combined (equivalence) or transitivity alone. Further, the difference in the number of simple discriminations presented in comparison-as-node training versus the other training structures is larger when the intended class size is greater than three or the number of classes is larger than two. We discuss the relevance of this analysis to interpretations of stimulus equivalence research, as well as some methodological and theoretical implications.  相似文献   
137.
In a series of experiments on immediate probed recognition for eight 3-digit numbers, it was shown that if the target modality involved auditory components and the effect of the similarity of the modality of the probe to that of the targets was controlled, unequivocal evidence was obtained for an auditory superiority effect (modality effect) for hit rates for the final items of the list. Moreover, false-alarm rates were significantly lower following targets with an auditory component than they were following silently seen targets. It is argued that this pattern of hits and false alarms is consistent with the idea that targets that have an auditory component yield memory representations that are better grouped as units than are those for targets that are only silently seen; in particular, if a new probe has a first digit that accidentally matches the first digit of a target item, it is more likely that the subject will mistakenly identify this new probe as old (give a false alarm) if the target has only been partially encoded because it was only silently seen.  相似文献   
138.
A highly popular method for examining the stability of a data clustering is to split the data into two parts, cluster the observations in Part A, assign the objects in Part B to their nearest centroid in Part A, and then independently cluster the Part B objects. One then examines how close the two partitions are (say, by the Rand measure). Another proposal is to split the data into k parts, and see how their centroids cluster. By means of synthetic data analyses, we demonstrate that these approaches fail to identify the appropriate number of clusters, particularly as sample size becomes large and the variables exhibit higher correlations.The authors express their thanks to the Sol C. Snider Entrepreneurial Center, Wharton School, for support of this project.  相似文献   
139.
Previous research has shown that the value of large future rewards is discounted less steeply than is the value of small future rewards. These experiments extended this line of research to probabilistic rewards. Two experiments replicated the standard findings for delayed rewards but demonstrated that amount has an opposite effect on the discounting of probabilistic rewards. That is, large probabilistic amounts were discounted at the same or higher rates than small amounts. Although amount had opposite effects on the discounting of delayed and probabilistic rewards, nevertheless, the same form of mathematical function accurately described discounting of both types of reward. The findings suggest that fundamentally similar, but not identical, processes are involved in decision making regarding delayed and probabilistic rewards. The implications of these findings for impulsivity and self-control are discussed.  相似文献   
140.
A program was developed to reduce indices of unhappiness that accompanied therapeutic exercise routines among people with profound multiple disabilities. Indices of unhappiness were recorded, using an observation system that had been validated through previous research involving happiness-related variables, while support personnel conducted exercises with 3 participants. A multicomponent program was then implemented that involved presenting highly preferred stimuli before, during, and after each exercise session. Results indicated that the program was accompanied by reduced indices of unhappiness for each participant relative to the traditional method of conducting the exercises, although changes in the preferred stimuli used with 1 participant were required before consistent reductions occurred. Results are discussed regarding the importance of reducing unhappiness indices as a means of enhancing aspects of the daily quality of life for people with profound multiple disabilities. Areas for future research are also discussed, focusing on expanding the unhappiness-reduction procedures to other routine events that may occasion indices of unhappiness.  相似文献   
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