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221.
222.
Sprague-Dawley (SD) rats were given X-irradiation (150 R) on Day 17 of gestation. After birth, all male pups were pooled once and then assigned randomly to irradiated mothers and control mothers. Offspring were administered an open-field test at about 7 weeks of age. The analysis was performed on the basis of two approaches: In the per subject approach, individual subject data (aggregation across Day 2 through Day 4) were treated as the basic unit of statistical analysis. In the per litter approach, double aggregation (aggregation across Day 2 through Day 4 for each subject and aggregation across subjects within each litter) was used. The per subject approach was slightly more sensitive as to the treatment effect, but it induced a reduction in the magnitude of eta squared. A principal component analysis was performed using eta squared together with those of several reference groups. Results were plotted on a map constructed from component scores. The characteristics of behavior in X-irradiated rats were very similar to those of the earlier stage of trials in terms of the location on the map. The postnatal maternal effect on open-field behavior was not serious and was adequately negligible in practice. A new fostering procedure was proposed and its advantages discussed.  相似文献   
223.
The authors examined age differences in perceived coping resources and satisfaction with life across 3 older-adult age groups (45-64, 65-74, and 75 years and older). The 98 participants represented healthy, socially active, community-residing adults. Group comparisons were made on 12 individual coping scales, and an overall coping resource effectiveness score was computed. No significant differences were found for 11 of the coping resources or for overall coping resource effectiveness. Similar consistencies in life satisfaction were found across the 3 age groups. The findings indicate that (a) for healthy adults, the oldest old cope at least as effectively as their younger counterparts, despite their likelihood of encountering increased levels of stress; and (b) psychologically, old age may be viewed as a time of resilience and fortitude.  相似文献   
224.
This study was performed after the tradition of F. C. Bartlett (1932), who demonstrated that memory reconfigures over time. The authors investigated the memory of young and older adults to examine the degree to which the aging process influences reconfigurative tendencies. From an initial sample of 53 participants, 20 young and 19 older adults completed 6 tests of recall for Bartlett's original text materials over an 84-day period. Consistent with the broad conclusions of Bartlett's study, reconfiguration was observed: Both young and older adults introduced errors into memory. Older adult recall was lower overall than that of young adults, and recall performance diminished over time. However, there was no difference between the performances of young and older adults with respect to incorrectly recalled intrusive elements.  相似文献   
225.
In previous studies of rapid elbow movements in young healthy men, characteristic task-dependent changes in the patterns of muscle activation when movement speed or distance was varied have been reported. In the present study, the authors investigated whether age or gender is associated with changes in the patterns of muscle activity previously reported in young men. Arm movements of 10 healthy older and 10 healthy younger participants (5 men and 5 women in each group) were studied. Surface electromyograms (EMGs) from agonist (biceps) and antagonist (triceps) muscles, kinematic and kinetic parameters, as well as anthropometric and strength measures were recorded. All 4 groups of participants showed similar task- (distance or speed) dependent changes in biphasic EMG activity. Similar modulation of the initial rate of rise of the EMG, integrated agonist and antagonist EMG activity, as well as their relative timing were observed in all 4 groups. Those results suggest that older individuals of both genders retain the control strategies for elbow movements used by young individuals. Despite the qualitative similarities in the patterns of muscle activation, the men moved more quickly than the women, and younger participants moved more quickly than older participants. Those performance differences could not be explained in terms of differences in body size and strength alone.  相似文献   
226.
Body posture, mainly represented by horizontal bed rest, has been found to be associated with cortical inhibition, altered perceptual and cognitive processing. In the present research, the influence of Head Down Bed Rest (HDBR) – a condition also termed simulated microgravity – on emotional responses has been studied. Twenty-two male subjects were randomly assigned to either Sitting Control or HDBR group. After 3-h, subjects attended to a passive viewing emotional task in which 75 IAPS slides, divided into 25 pleasant, 25 neutral and 25 unpleasant, were presented in random order for 6 s each, while EEG was recorded from F7, F8 and Pz locations. Results showed in Sitting Controls the expected greater P300 and Late Positive Potential (LPP) to pleasant and unpleasant compared with neutral slides, an effect which indicates greater processing of emotional arousing stimuli. The HDBR group showed smaller non-significant differences among all emotional conditions in both ERP components. Arousal and valence subjective evaluations, typically less sensitive to experimental manipulation, did not differentiate groups. The observed ability of HDBR to inhibit cortical emotional responses raises an important issue on the risk that astronauts underestimate a dangerous/threatening situation or that long-term bedridden inpatients develop depressive symptoms.  相似文献   
227.
ABSTRACT

This study examines the patterns and relationships between twelve independent variables and the expressed subjective well-being of older adults within that classic community setting of the Lynds' “Middletown.” The twelve variables include measures of church attendance, religious activity, religious conservatism/liberalism, subjective health status, social participation, importance of leisure, participation in physical activity, age, sex, marital status, and level of education.  相似文献   
228.
ABSTRACT

This study examined the association between health status, stress, depression, satisfaction with the relationship with the religious community, alienation from significant persons, racial/cultural identity and “aging in place,” as measured by length of time in the same religious community, for a purposive sample of 72 African American nuns. Aging in place was significantly associated with perceptions of better health status, less stress and depression and greater satisfaction with relationships with the religious community. However, the study also found that the longer the nuns lived in their respective communities, the less racially/culturally identified they became. These findings underscore the need for finding ways to keep nuns in their religious communities as they age and to provide avenues of racial/cultural expression for African American nuns.  相似文献   
229.
Analyses examined both positive emotion (PE) at baseline and change in PE from baseline to follow up as predictors of change in functional status (FS). Initial models examined baseline PE, and change in PE, as predictors of change in FS adjusted for baseline PE, negative emotion (NE), FS, and age and gender. Final models included additional adjustments for frequency of social contact, marital status, body mass index, smoking status, drinking behavior, and comorbidity at baseline. Baseline PE was a predictor of change in FS, adjusted for NE, age, and gender (p?=?0.033). Additional covariates reduced the effect of baseline PE as a predictor of change in FS (p?=?0.115). Change in PE was a significant predictor of change in FS – increases in ratings of PE over time were associated with less decline in FS (p?=?0.001). The association for change in PE remained significant in the fully adjusted model (p?=?0.004). Results replicate our prior findings.  相似文献   
230.
Humour skills programmes are believed to assist in improving emotional well-being by increasing self-efficacy, positive thinking, optimism and perceptions of control, while decreasing negative thinking, perceptions of stress, depression, anxiety and stress. The study aims to evaluate a programme investigating this possibility. Volunteers from the community (37 females and 18 males, aged M?=?38 years) were randomly assigned to a humour group, a social group or a non-intervention control group. The programme, consisting of a manual and a booklet of measures assessing indices of well-being, was administered over an 8-week period. Data were collected at baseline, post programme and at 3-month follow-up. Results revealed that unlike the control and social groups, the humour group demonstrated a significant increase in several indices of emotional well-being. Specifically, increases occurred with self-efficacy, positive affect, optimism and perceptions of control, while decreases were found in perceived stress, depression, anxiety and stress levels.  相似文献   
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