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121.
I examined preweanling rats' (Rattus norvegicus) expression of ultrasounds and secretion of ACTH when exposed to unfamiliar adult male rats or to their mothers. Pups at 7 days of age produced similar levels of ultrasonic vocalization near both unfamiliar males and mothers. However, these pups could discriminate familiar from unfamiliar adults because ACTH was significantly higher in pups near adult males than in those near mothers. At 14 days of age, pups avoided adult males but not their mothers; therefore, adult males represented a significant threat. Importantly, 14-day-old rats significantly reduced ultrasound production only when near adult males. Pups at 21 days of age no longer emitted ultrasounds when socially isolated or when near conspecific adults. In addition, 14- and 21-day-old rats produced similar elevated ACTH levels across stimulus conditions. Results show significant changes in preweanling rats' responses to conspecific adults. 相似文献
122.
This study sought to investigate the effects of mild head injury on a particular type of cognitive ability, verbal analogical
reasoning. The performance of 19 individuals with head injuries was compared to a group of 30 control subjects matched for
age, education, and gender on 100 verbal analogies. Solution times and error rates were modeled. Unstandardized regression
weights for individual subjects were correlated with subjects’ performance on a number of standardized ability tests. Results
showed that compared to the control subjects, the head injured subjects: (a) were significantly slower to solve the analogies,
and were particularly slow to perform certain processes: encoding/inference and comparison; (b) tended to show greater variability
in performance; and (c) had data that had a poorer componential model fit. The data suggest that analogical reasoning is affected
by a head injury, and that certain information processes may be responsible for performance deficits. 相似文献
123.
Measures of spatial cognition, neighborhood knowledge, and neighborhood use from the research described by Walsh, Krauss, and Regnier (1981) were examined to determine if laboratory tests of spatial cognition were significant predictors of older adults' use of their neighborhoods. The overall results show that laboratory-based measures of spatial cognition and subjects' knowledge of their neighborhoods are both significant predictors of their use of neighborhood goods and services. The ability to learn and remember the location and orientation of objects, when contextual cues were not provided at test, was more predictive of the participants' neighborhood use than either the participants' number of years in the neighborhood or their mobility. Spatial memory as measured by the Educational Testing Service Building Memory task predicted neighborhood knowledge, which was predictive of neighborhood use. 相似文献
124.
The construct accessibility model (CAM) holds that constructs are most likely to influence behavior when they are accessible in memory. While the theory of reasoned action sees intention as an important determinant of behavior, the CAM predicts that the intention to act upon a given health behavior is not likely to be acted upon unless the intention is in an accessible state. Therefore, people who frequently talk about or think about using condoms are likely to have condom related constructs available and use them when needed. This paper reports findings from the pilot phase of a project to identify beliefs which influence condom use in Hispanic and African-American youth living in Detroit. 15 male and 15 female Hispanics and 17 male and 17 female African-Americans aged 15-21 years of mean and median age 18.5, were interviewed face-to-face in 1989 with the goal of identifying condom beliefs which may influence their condom use. 80-82% of male participants, 53% of Hispanic females, and 100% of Black females had experienced sexual intercourse, with age at first intercourse ranging between 13.1 and 16.5 years. 88% of Black women and 7% of Hispanic women were pregnant at the interview. Regarding participants' level of preventive knowledge, all but 1 recently immigrated Hispanic female knew HIV was transmitted by needles and sexual intercourse. 87% of Hispanics and 94% of African-Americans responded that condoms protect against AIDS, but only 13% of Hispanics and 47% of African-Americans knew that nonlatex condoms do not. Some participants expressed concern that condoms reduce sensitivity and/or break during intercourse. Controlling for sexual activity, 25% of Hispanic females, 83% of Hispanic males, 71% of African-American females, and 80% of African-American males had ever used a condom; no Hispanic and 14% of Blacks reported using them consistently in the 12 month period preceding the interview. With 100% of African-American males and 97% of Black females reporting thinking about using condoms compared to 80% of Hispanics, the study findings suggest that condom intentions are more accessible in African-Americans than among Hispanics. 相似文献
125.
Mikawa JK Morones PA Gomez A Case HL Olsen D Gonzales-huss MJ 《Hispanic journal of behavioral sciences》1992,14(4):421-433
Hispanic Americans have one of the highest rates of HIV seroprevalence among all ethnics groups in the US, with high rates being especially noticeable among women and children. Were it known which cultural factors have the most influence on whether Hispanics engage in high-risk behavior for HIV transmission, prevention interventions could be targeted accordingly. To that end, this study was mounted to identify which Hispanic cultural factors relate to condom use. 117 males and 73 females aged 17-56 years of mean age 25.67 were surveyed in Washoe county, Nevada. These mostly young adults had recently immigrated to the western US. It was initially posited that fate orientation, male- female relationships, family relationships, machismo behavior, and religion would have equal influence with respect to condom use. Analysis found that condom use was largely associated with and determined by men who are the principal buyers of condoms. A machismo attitude toward protecting women by using condoms was also associated with condom use. Neither fate orientation with respect to AIDS, nor religion were important determinants of condom use, even though 86.5% of the respondents were Catholic. The degree to which respondents adhered to traditional Hispanic cultural values was influenced by the degree of education and acculturation. On the basis of these findings, the authors suggest targeting AIDS prevention messages to males, while emphasizing the protection of women through condom use. They also suggest that both education and acculturation levels be assessed before implementing prevention programs. 相似文献
126.
127.
This study examined whether chronic physical exercise activity is associated with better neurocognitive performance in older adults. One hundred five men participated in 1 of 3 age groups (18-28, 35-45, and 60-73). For each age group, subjects were classified as high or low in fitness on the basis of self-reported activity levels and the results of a submaximal bicycle ergometer test. A comprehensive battery of neuropsychological tests was administered to each subject, and older subjects scored significantly lower than the younger groups on most tests. Significant differences between high- and low-fit subjects were found only on tasks with heavy visuospatial demands, and these differences were most notable in the older adult group. These findings suggest that participation in aerobic exercise activity selectively preserves some cognitive functions that normally decline with age. The benefits of activity appear to be most evident on tasks that require visuospatial processing. 相似文献
128.
Older adults' life satisfaction can be better understood in light of their personal goals. This study of 179 elders examined (a) how goals correlate with satisfaction, (b) whether elders maintain satisfaction by accommodating goals to past losses, and (c) how correlations between satisfaction and key predictors differ among groups with different goals. Satisfaction was related positively to social maintenance and energetic life-style goals and negatively to concerns for improvement, disengagement, stability, and reduced activity. Past losses were correlated with current goals but not with satisfaction, consistent with the notion of accommodation. A cluster analysis identified 5 patterns of goals: high demand, age prescribed, self-focused, socially engaged, and low demand. Correlations between satisfaction and other predictors differed by cluster, suggesting that the determinants of elders' satisfaction depend on personal goals. 相似文献
129.
Gerontologists have long been concerned with the impact of individual-difference factors on memory. This study used a large sample (N = 2,495) of adult volunteers aged 18 to 90 years to determine if a set of individual-difference variables--vocabulary, education, depression, gender, marital status, and employment status--mediates the effects of aging on a wide range of laboratory-analogue tests of everyday memory. The data indicated that age was consistently the most significant predictor of memory performance, followed by vocabulary and gender. Vocabulary totally mediated age effects on a prose memory measure, and partial mediation of aging effects--primarily by vocabulary and gender--was observed on 5 other memory tests. These data suggest that when health samples of volunteers serve as research subjects, these individual differences can affect some memory test scores, but age remains the best overall predictor of memory performance. 相似文献
130.
Short-term memory for actions was investigated for young adult and elderly adult subjects with the Brown-Peterson procedure at retention intervals of 0 and 15 s. The short-term memory trials were followed by the long-term recall of the prior to-be-remembered actions. The 15-s retention interval was filled either with no activity or with 1 of 3 different interfering activities. Verbal interference had little effect on short-term memory at either age level. Actions performed in the interval either by the subjects or by the experimenter produced significantly lower recall scores at each age level, with the decrement being more pronounced for the elderly than for the young subjects. The long-term memory results indicated that successful short-term recall enhanced later long-term recall, regardless of age level. 相似文献