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181.
I used longitudinal data to examine relationships between sibling variables and young adults' status attainment at different levels, based on earlier measures of adolescents' educational and occupational aspirations. My analyses involved 21-year-old Australians from Anglo-Australian, Greek, and Southern Italian families. Regression surfaces were plotted from models that included terms to test for possible linear, interaction, and curvilinear associations among the variables. My study showed that the number of children in a family and birth order continue to be significantly associated with young adults' status attainment, even after incorporating the mediating influences of adolescents' aspirations. The investigation also suggested ethnic group differences among sibling variables, adolescents' aspirations, and young adults' status attainment.  相似文献   
182.
Previous studies have demonstrated that effortful attempts to secure positive outcomes or avoid negative outcomes produce significant increases in systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR). Although these effects of active coping on cardiovascular reactivity are central in current psychosomatic theories, virtually all of the research to date has used impersonal, asocial tasks. Our two studies examined the cardiovascular effects of effortful attempts to influence other people. In Study 1, male subjects attempting to influence the opinions of their discussion partner to improve their own chances of winning money displayed significantly greater SBP, DBP, and HR reactivity. In Study 2, we obtained similar effects on SBP and DBP reactivity in men and women, while both preparing an influence attempt and making that attempt. Furthermore, reactivity levels were larger as the magnitude of incentive for successful persuasion increased. Implications of this interpersonal equivalent of active coping for the development of cardiovascular disease are discussed.  相似文献   
183.
Previous psychophysiological research has demonstrated that both anger expression and anger suppression are related to cardiovascular responses, but in an inconsistent fashion. The present study tested the following hypotheses: (a) that the influence of anger expression style on psychophysiological responses would be limited to Ss exposed to an anger instigation, and (b) that the specific pattern of psychophysiological responses would vary as a function of whether Ss were induced to use their preferred vs. nonpreferred mode of anger expression style in response to the instigation. Seventy-eight male college undergraduates were randomly assigned to work on a task with either an annoying or a pleasant confederate and subsequently to write either a negative or a positive evaluation of the confederate. Blood pressure was measured intermittently and heart rate continuously throughout task performance and a subsequent 15-min rest period. Ss' preferred method of anger expression had been previously assessed by a self-report questionnaire. Systolic blood pressure results generally were consistent with the hypotheses. Implications of the findings for the etiology of cardiovascular diseases are discussed.  相似文献   
184.
185.
The peak procedure was used in two experiments to study pigeons' ability to time multimodal events. In the first experiment, birds were trained to time a single event consisting of a 9-s tone or light followed by a 21-s fixed interval associated with a signal of light or tone (signal of the other modality). On occasional empty trials, different lengths of the first signal were followed by a long period of the second signal. Peak response times as a function of the duration of the first signal were linear and had a slope of close to one in all birds. This indicates that the birds were timing only the second signal. In a second experiment, two complex events were used in training. One consisted of a 9-s tone or light followed by a 21-s fixed interval associated with a light or tone. The other consisted of a 21-s tone or light followed by a 9-s fixed interval associated with a light or tone. Different durations of the first signal were again used on empty trials. Peak response times as a function of the duration of the first signal were again linear in all birds. The slope of the function was less than one but greater than zero for 3 birds. This indicates that these birds were partly timing the entire complex event of 30-s duration and partly timing only the second signal of the event. A model is proposed in which the bird takes as a criterion for timing a weighted average of different target criteria. Comparisons with the performance of rats are made.  相似文献   
186.
The stability limits of erect stance are described as a geometrical structure in a movement space. Mechanical properties and response latency, a neural property, are determining factors for the stability limits. Standing stability limits of adults and young children are compared, and a simple scheme is suggested by means of which infants can discover the stability limits as they learn to stand. The mechanics of different standing movements are discussed because their spatial temporal properties relate directly to their different stability limits. The combination of the stability limits for different movements gives a total set of stability limits, a different structure for adults than for children.  相似文献   
187.
One of the significant limitations of the motor control and skill acquisition domain is that the theories, models, and hypotheses are, in most cases, task specific. Many lines of theorizing fail to hold up under even small changes in task constraints, although clearly the field does have some robust phenomena. It is proposed that a broader consideration of the role of task constraints, which is grounded in the methodology of nonlinear dynamics, may help to formulate a more general action theory of coordination and control.  相似文献   
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189.
Two groups of American undergraduates (moderate and heavy social drinkers) completed a matrix task and received either positive or negative feedback on their performance. Following this they were given a maze task, which was designed so that cheating could be detected. Heavy drinkers cheated more than moderate drinkers under success conditions (positive feedback). Heavy drinkers who received positive feedback also cheated more than heavy drinkers who received negative feedback. The results are interpreted in terms of self-handicapping theory.  相似文献   
190.
There is increased evidence that infants who receive poor quality social stimulation from their primary caregiver are at risk for later developmental difficulties. This paper describes a preventive intervention for mother-infant dyads exhibiting impaired patterns of social interaction. An impaired relationship with the primary caregiver has been found to be associated with social and emotional deficits in early childhood as well as with significant psychopathology in adulthood. The intervention consisted of group treatment of mothers and their infants. Each group session has 4 subsections which, together, were directed towards improving the mothers' ability to relate in a stimulating and nurturant manner to their children. Types of intervention included didactic instruction, modeling, and interpretation of the infant's behavior. Qualitative data suggested that the group intervention has positive effects on the mother-infant dyads.  相似文献   
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