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51.
This work examined the effect of age on the ability to learn multiplicative combination rules. Participants learned the multiplicative relationship between daily tobacco intake, daily alcohol intake, and risk of esophageal cancer. The hypothesis was that younger adults would learn to implement a multiplicative combination rule and older adults would not, despite feedback. Among the younger adults, complete rule learning took place. Before receiving feedback, they used an underadditive rule, a result consistent with previous studies. After only a limited amount of feedback, they learned to use a multiplicative rule. Even after receiving feedback, however, the older adults still showed difficulties in using the multiplicative rule. These results strengthen the proposition by Chasseigne, Mullet, and Stewart (1997) that the differences between younger and older adults in function learning are related mainly to flexibility of functioning.  相似文献   
52.
Although the effect of low socioeconomic status on the health of adolescents has been documented, the mechanism by which this occurs is not well understood. Furthermore, improving adolescent health through public health policy typically requires the presence of one or more modifiable risk factors which can be targeted for intervention. In spite of the well-documented negative associations between poverty and health, few modifiable risk factors have been identified. This study used the Evans-Stoddart Model of Health and Well-Being as a framework to examine data on 1,759 adolescents, aged 12 to 19, collected as part of the 1994 National Population Health Survey. Results not only confirm the relationship between income and health, but suggest how the pathway operates through the social environment, lifestyle differences, access to health care, and a reduced sense of self-esteem and self-mastery. Bivariate and multivariate analyses found positive associations between physical activity levels and self-esteem and mastery. We interpret these findings as preliminary evidence that it might be possible to buffer the impact of poverty on health through policies which increase physical activity levels among those living in poverty. Such policies could also include a secondary goal of increasing the activity levels among inactive adolescents who are not living in poverty, as they will derive benefits from this increase, both psychologically and physiologically.  相似文献   
53.
Cognitive biases and cognitive distortions have been implicated as important factors in the development and maintenance of many disorders. The concept of thought-shape fusion (TSF) in eating disorders was developed by Shafran, Teachman, Kerry, and Rachman (British Journal of Clinical Psychology 38 (1999) 167) as a variant of thought-action fusion, described by Shafran, Thordarson and Rachman (Journal of Anxiety Disorders 10 (1996) 379). TSF occurs when thinking about eating certain types of food increases a person's estimate of their shape and/or weight, elicits a perception of moral wrongdoing, and/or makes the person feel fat. Shafran et al. (1999) examined both the psychometric and experimental properties of TSF in an undergraduate sample. This paper reports an extension of this work to a clinical group (N=20) of patients with anorexia nervosa. After completing a set of relevant questionnaires, participants were asked to think about a food which they considered extremely fattening. They were then asked to write out the sentence, "I am eating--.", inserting the name of the fattening food in the blank. After being asked to rate their anxiety, guilt, feelings about their weight, morality, etc., participants were given the opportunity to neutralize their statement in any way they chose. The majority of the participants neutralized in ways consistent with the findings of Shafran et al. (1999). The results are discussed in terms of cognitive-behavioural formulations of eating disorders, and of the influence of cognitive biases and cognitive distortions on the processing of information relevant to food, weight and shape in anorexia nervosa.  相似文献   
54.
Normal language development was studied in 310 pairs of 4-year-old twins born in the United Kingdom in 1994. Twins were assessed individually in their homes on a diverse battery of language and nonverbal measures. Rotated factor analyses indicated the presence of a general Language factor (L) as well as a general Nonverbal (NV) factor. Moderate genetic influence was found for both L and NV abilities. Bivariate genetic analysis estimated a genetic correlation of .63 between L and NV abilities, implying that over half of the genetic influence on L overlaps with genetic influence on NV. These results suggest that at age 4, genetic influences on individual differences in language overlap substantially with genetic influences on individual differences in other cognitive abilities, although perhaps less so than later in development.  相似文献   
55.
The attachment and social rank systems are biological-evolutionary systems that can serve as models for conceptualizing family interaction. By exploring both their unique and interrelated impact on affect regulation, we can differentiate between processes that foster healthy growth and those leading to individual psychopathology. This perspective facilitates the integration of biological and psychological models, and has therapeutic implications. It also integrates well with other family therapy models.  相似文献   
56.
The observation of women's groups in Italy has made it possible to outline specific developmental processes. Clinical illustration also suggests the emergence of specific group areas such as "interchangeability," which are not seen in mixed-gender groups. The safe and confident atmosphere of interchangeability stimulates the relaxation of defences and self boundaries. As a consequence, it allows profound exchanges, which have an immediate impact in enhancing the sense of value and self-esteem of group members. Further therapeutic potentialities of "interchangeability" are described. Women in the here and now acquire the strength necessary for reexamining and psychoanalytically working through unconscious unresolved gender identifications and consequent problems in present relationships.  相似文献   
57.
Dyads of 4- and 5-year-old friends and nonfriends attending preschools in central Italy were identified by friendship nominations. The 217 dyads of friends and non-friends participated in 2 closed-field tasks designed to simulate real-life situations of potential conflict. In the 4-year-old cohort, there were no significant differences in the behavior of the partners in either of the situations. However, at age 5 years, friends respected the rules of a fast-paced competitive game significantly more than did nonfriends. In discussing how to share a single object (a chocolate egg with a toy inside), 5-year-old friends were more likely to reach agreement than were nonfriends. The results suggest important developmental changes in the processes of negotiation and sharing within the preschool years.  相似文献   
58.
Olivopontocerebellar atrophy (OPCA) is a still debated condition, of which motor disruption is the most common feature. A high incidence of associated mood disorders may exist, but there are few studies on concomitant cognitive impairment. Our aim was to assess whether there is reading and writing disruption in olivopontocerebellar atrophy (OPCA). 6 patients were administered different reading and writing tasks. Scores were then compared to those obtained by healthy volunteers. There was an evident impairment in reading and writing execution in our patients compared to those of the control group. On the contrary, no difference could be found in abstraction, problem-solving, and memory tasks. We discuss the results, debating the role of the cerebellum in the conscious process of cognition or in ocular movement control (necessary for reading and writing fluidity and effective execution) and in the dynamic activation of all the cerebral cortex mediated by the diffuse projection to the reticular system.  相似文献   
59.
In karate, performance also depends on a correct body shape, and the repeatability of standardized movements conditions the effectiveness of techniques. The execution of mae-geri-keage (frontal snap kick) was studied in 13 karateka (1st-5th dan). The 3D trajectories of 13 body landmarks were analyzed by an optoelectronic instrument while each karateka performed 10 repetitions of the movement. For each karateka and repetition, the standard deviations of the spatial coordinates x, y, z for each landmark were computed. A total standard deviation of the single participant was also calculated. Two experienced karateka performed with the best repeatability (smaller standard deviation) while executing the studied kick. Generally, the best repeatability was observed in the horizontal plane. The lower variability was observed in hips and head. Ankle and knee of the dominant limb had the worse. The method could detect athletes particularly gifted for the discipline. Moreover, it could help in the identification of those parts of body that do not repeat the movement with the desired precision.  相似文献   
60.
The present study describes a preferential tongue movement in cats, suggesting a so-called "tonguedness" also in animals. 8 cats (66.7%) showed right-tonguedness and 3 left-tonguedness.  相似文献   
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