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851.
Experiments were conducted in which Ss made classification, recognition, and similarity judgments for 34 schematic faces. A multidimensional scaling (MDS) solution for the faces was derived on the basis of the similarity judgments. This MDS solution was then used in conjunction with an exemplar-similarity model to accurately predict Ss' classification and recognition judgments. Evidence was provided that Ss allocated attention to the psychological dimensions differentially for classification and recognition. The distribution of attention came close to the ideal-observer distribution for classification, and some tendencies in that direction were observed for recognition. Evidence was also provided for interactive effects of individual exemplar frequencies and similarities on classification and recognition, in accord with the predictions of the exemplar model. Unexpectedly, however, the frequency effects appeared to be larger for classification than for recognition.  相似文献   
852.
Spontaneously hypertensive (SHR), Wistar-Kyoto (WKY) normotensive, and Sprague-Dawley (SD) normotensive rats were either reared by their natural mothers (controls) or fostered to a mother of one of the other strains. The effects of rearing environment were assessed by measures of body weight at weaning and adult resting mean arterial blood pressure (MAP) and heart rate (HR). At weaning, SHR control rats weighed less than WKY controls which in turn weighed less than SD controls. SHR and WKY rats reared by SD mothers weighed significantly more than their respective controls, whereas SD rats reared by either SHR or WKY mothers weighed less than SD control rats. Manipulation of the maternal environment was attended by a change in adult resting MAP in only one group. SHR rats reared by SD mothers had MAPs which were significantly lower than SHRs reared by their natural mothers. No within-strain adult HR differences were observed between control and cross-fostered groups. These data indicate that the effects of cross-fostering on adult resting MAP previously reported for SHR and WKY animals are generalizable to another normotensive strain. That is, genetically hypertensive (SHR) animals exposed to a normotensive (WKY or SD) maternal environment display a reduction in adult resting MAP, whereas hypertension or an increase in adult MAP is not induced in normotensive rats (WKY or SD) as a consequence of exposure to a hypertensive maternal environment.  相似文献   
853.
The aim of this study was to assess the validity of the notion that anxiety influences maternal style in monkeys. To this end, we investigated the correlations between measures of the quality of mother-infant relationship and scratching, a behavior pattern that reflects a state of anxiety. The subjects were seven group-living macaque mothers and their infants observed during the first 12 weeks postpartum. Postpartum scratching by the mothers was positively correlated with both maternal possessiveness and maternal warmth, two composite measures of the quality of mother-infant relationship that reflect a possessive and attentive maternal style. Evaluation of the correlations between maternal rank and scratching before and after parturition indicated that interactions with their infants, not those with other group companions, were the main source of anxiety for the mothers. These results support the notion that anxiety influences maternal style in monkeys and suggest that studies aimed at investigating physiological and social correlates of maternal emotionality in nonhuman primates could use scratching as a useful and simple behavioral measure.  相似文献   
854.
855.
Previous research has demonstrated greater attention toward disagree arguments and a greater persuasibility during relative right than during relative left hemisphere activation. This experiment was performed to conceptually replicate and extend these findings to memory stages in the processing of persuasive arguments. The experiment used induction of lateral orientation of attention as the means to selectively activate regions of the brain in normal right-handed subjects. The results showed the expected significant interaction for correct recall as a function of agreement with the argument and hemisphere activated. There was greater recall of agree arguments during left hemisphere activation and greater recall of disagree arguments during right hemisphere activation, as predicted. The effect for recognition memory was in the same direction, but was statistically nonsignificant. These findings support previous research on cerebral asymmetries in the processing of persuasive arguments. This phenomenon is discussed as a possible outcome of asymmetries of affect.  相似文献   
856.
The detectability of a target pattern presented briefly with a number of similar nontarget patterns varies as a function of the spatial location of the target. Previous work attributes these detectability gradients to a visual search process--a non-eye movement serial scan--that examines a decaying neural representation of the image. (Heron, 1957; Efron, Yund, & Nichols, 1987, 1990a,b,c; Yund, Efron, & Nichols, 1990a,b,c). The results reported in the companion paper (Ostrosky-Solis, Efron, & Yund, 1991) indicated that literacy did not affect overall performance levels but did influence scanning behavior: "...reading, or learning to read, caused the scanning mechanisms of literate subjects to adopt more consistent scan paths, from subject to subject, than they would have adopted without this reading experience." The purpose of the present experiment was to determine the effect on this scanning mechanism, if any, of an entirely different type of visual experience--the high-speed visual processing required of tennis players. Unlike reading which requires the linguistic interpretation of a highly structured visual input, tennis skill requires rapid target detection and tracking in three-dimensional visual space as well as large scale visual-motor coordination. As in the previous experiments, subjects were required to detect a vertical stripe pattern among a number of similar non-target patterns. The experiment was performed on a group of 52 tennis players and on an age- and sex-matched group of 52 non-tennis players. The overall accuracy of target detection was greater among the tennis players than among the non-tennis players and, of more interest, there was a significant difference in the detectability gradients. The detection advantage of the tennis group seemed to reach its maximum in the first half of the scan and then to deteriorate as the scan proceeded. These results indicate that visual experience other than reading can affect the habitual activity of the scanning mechanism.  相似文献   
857.
Gender differences in health-related quality of life   总被引:1,自引:0,他引:1  
In 1986 the life expectancy at birth was 71.3 years for males and 78.3 years for females--providing a 7-year advantage for women. Although women live longer, it has been reported that they paradoxically experience more physical and psychological illnesses. In this article, we estimate the expected well-years or quality-adjusted life years for men and women in the general population. The data were obtained in a random sample of 1,034 residents of San Diego. The well-life expectancy uses standard life expectancies with adjustments for quality of life. The well-life expectancy for men was 59.8 years; for women, it was 62.7 years. Thus, the quality adjustment had significantly more impact on women (15.6 years) than on men (11.5 years). Age-specific estimates of health-related quality of life suggested a male advantage before age 45 and a female advantage after age 45. The benefits of well-years of life as a public health statistic are discussed.  相似文献   
858.
Symptom schemata in chronic respiratory patients   总被引:1,自引:0,他引:1  
In view of evidence that illness prognoses and adaptive functioning may be influenced by the accuracy of people's knowledge about their physical symptoms, the present study extended these findings to the chronic care population. It was hypothesized that individuals hold beliefs and develop theories about their physical symptoms and that the accuracy of these beliefs is predictive of the individuals' general level of adaptive functioning. A modified version of an instrument designed to measure the accuracy of illness schemata was employed with a sample of 31 chronic respiratory patients. Accuracy rating correlated positively and significantly with ratings of adaptive functioning, whereas no relationship was observed between adaptive functioning and severity of the patients' medical condition. Well-informed patients functioned at a higher level physically, psychologically, and socially than less-informed patients. These findings point to the importance of patient education for prognosis. Possible mediating factors are discussed.  相似文献   
859.
Rapid growth has been observed in recent years in the number of women entering traditionally male blue-collar occupations, yet researchers have paid little attention to this pioneering group. The present study undertook a comparison of the job conditions of two groups of nontraditional women workers, tradeswomen (N=71), and transit workers (N=151); a third group, school secretaries (N=389), was studied as a comparison group of traditionally female workers. Results from a 16-page mail questionnaire revealed that women in traditionally male occupations encountered significantly more adverse working conditions than did their traditional counterparts, and, in addition, reported significantly less satisfaction and more stress at work. Tradeswomen were the most likely to experience sexual harassment and sex discrimination, and black tradeswomen to experience race discrimination. The degree of job satisfaction expressed by the secretaries was unexpected, since most evidence suggests that clerical workers lack autonomy, and encounter boredom and routinization on the job. These findings are discussed in terms of gender segregation and the need to focus future research efforts on specific occupational groups in order to make appropriate policy recommendations as well as to provide help for women in these jobs.This research was supported by grants from the National Institute for Occupational Safety and Health (Grant No. 1 RO1 OH02162-01A1) and the College of Health and Human Development, The Pennsylvania State University. The authors wish to acknowledge the invaluable contributions of Patty Lambert, Ming Qi Wang, Mary Harmon, Joseph Vasey, Gina Jay, Darrell Harvey, and Haleh Rastegary.  相似文献   
860.
Even though in Italy, as in the majority of Mediterranean countries, the increase in suicide rates is not among the highest in Europe, between 1969 and 1989 it showed a sharp upswing (+43% among males and +31% among females). In terms of geographical differences, the regions with the highest suicide rate are the northern ones (up to twice the national average). The age groups with the highest suicide risk are those over 74 years (in 1989 the rate among males over 65 was the highest of all: 31.3 per 100,000). The differences in the between-sexes distribution show that among females over 65 years old the suicide rate rose by 70% between 1974 and 1989, versus 77% for males of the same age. The preliminary epidemiological results of one of two Italian centers are presented. These centers are collaborating with the WHO/EURO Multicenter Study on Parasuicide; parasuicide rates are higher for females than for males (55.9 per 100,000, as against 38.1 for males), while the age group at highest risk is seen to be young women (15-24 years), with a specific rate of 115.6.  相似文献   
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