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801.
Age differences in the acculturation process   总被引:1,自引:0,他引:1  
Age differences were assessed in a conceptual model that seeks to explain how acculturation affects psychological well-being among Mexican Americans. The data were from a national probability sample of 859 persons of Mexican decent. It was hypothesized that low acculturation creates financial stress. Moreover, low acculturation and financial stress were in turn predicted to erode feelings of personal control and self-esteem. Finally, diminished feelings of control and low self-esteem were hypothesized to exert a negative impact on psychological well-being. When data from respondents of all ages was assessed, empirical support was found for all of the hypotheses except the linkage between acculturation and financial stress. However, few age differences emerged in the model. The authors conclude that older Mexican Americans may not be more vulnerable to the stressors associated with acculturation.  相似文献   
802.
Age, exercise, and coding performance   总被引:1,自引:0,他引:1  
We investigated the effects of exercise on the coding performance of young and older subjects. Hypotheses were tested that exercise either facilitates spatial localization or reduces susceptibility to distraction in older subjects. In a balanced design, we administered Digit Symbol and Symbol Digit coding tasks to exercisers and nonexercisers at two age levels under conditions of low or high within-task interference. The findings showed higher performance by the exercisers than by the nonexercisers only at the older age level and only with the Symbol Digit task. These findings support the hypothesis that exercise compensates for a loss of spatial localization skills with age. We found no evidence that susceptibility to distraction either increased with age or was affected by chronic exercise.  相似文献   
803.
Deficits in semantic encoding have been described in patients with frontal lobe disease who also show memory impairments. As a group, patients with multiple sclerosis (MS) exhibit memory impairment, fail to make effective use of semantic encoding to aid memory, and perform poorly on verbal fluency and concept formation tests which are sensitive to frontal lobe damage. In the present study the semantic encoding capacity of MS patients was measured using a modification of Wicken's release from proactive interference (PI) paradigm. Individual patients varied considerably in the severity of their impairments on verbal fluency, verbal recognition memory and on Wisconsin Card Sorting Task, but even patients who evidenced both memory impairment and signs of frontal lobe dysfunction showed normal release from PI after a categorical shift. Memory disturbances in MS are unlikely to result from an incapacity for semantic encoding, which seems preserved in MS, but may arise instead from deficits in processing information rapidly.  相似文献   
804.
This study compared the temporal organization of graphic movements executed either actually or mentally. Six subjects had to perform two tasks, writing a sentence and drawing a cube, either as a real performance or as an imagined one, with either the right or the left hand, and with either a small or a large tracing amplitude. In the same subject, for the same hand, mental and actual movement times were both very stable and very close from trial to trial regardless of the tracing amplitude. Thus, mental movements mimic closely real movements in their temporal organization and are likely to involve the same planning program.  相似文献   
805.
Karl E. Peters 《Zygon》1989,24(4):469-485
Abstract. Developing a scientifically grounded philosophy of cosmic evolution, and using the moral norm of completeness as dynamic harmony, this paper argues that humans are a part of nature in both its conserving and emergent aspects. Humans are both material and cultural, instinctual-emotional and rational, creatures and creators, and carriers of stability and change. To ignore any of the multifaceted aspects of humanity in relation to the rest of nature is to commit one of a number of fallacies that are grounded in a dualistic-conquest mentality. Examples of some new developments in philosophy and theology, metaphorical images, and ritual show how to overcome dualism in favor of a dynamic harmony of humanity within nature.  相似文献   
806.
Prior to assuming the upright crouching posture over their pups during nursing bouts, lactating rats typically engage in several oral behaviors, including nuzzling, licking and rearranging pups. By acutely depriving dams of various aspects of perioral stimulation from pups (with anesthesia of the mystacial pads or of the tongue, with mouth suturing, or with muzzling), we found the following: (1) Distal stimulation from pups maintains proximity-seeking behavior, but is insufficient to stimulate nursing behavior. (2) Lack of tongue feedback decreases pup licking and hastens the onset of crouching. (3) Snout, but not tongue, contact with pups is required for hovering over them. (4) The position of the dam while hovering over her litter enables the pups to gain access to her ventrum, thereby provoking her upright, crouching posture. (5) Older pups are capable of bypassing the dam's perioral attentions and stimulating crouching directly by burrowing under the dam's ventrum.  相似文献   
807.
The physiological effects of racism, as a stressor, were examined as they related to blood pressure (BP) and anger experiences in Black college students. Current research has failed to consider the stressful effects of racism as a factor contributing to the higher incidence of essential hypertension among Blacks. Twenty-seven Black college students viewed three excerpts showing racist situations involving Blacks; anger-provoking, nonracist situations; and neutral situations. After each scene, BP was taken, and a mood checklist was administered. The Framingham Anger Scale and the Anger Expression Scale were administered. Analyses revealed that BP significantly increased during the presentation of racist stimuli but not of anger-provoking or neutral stimuli. Self-reports of state anger, as measured by the mood checklist, were significant for both the anger-provoking and racist stimuli. BP scores were significantly correlated to the two trait anger measures. Exposure to racist stimuli was associated with BP increases among Blacks. Such cumulative exposure to racism may have important implications for the etiology of essential hypertension.  相似文献   
808.
A cross-sex difference on one variable is often hypothesized to be related to a gender difference on a second variable. However, caution should be exercised in making such comparative hypotheses. We gathered the expected and actual examination grades for 168 female and 163 male college students. As in prior research, males had higher expectancies than females (p<.05). But analysis of the intrasex regression equations indicated that the relationship of expectancies to performance was different for women than it was for men. Thus, a cross-sex difference in expectancies did not correspond to a parallel difference in grades. This finding highlights the potential hazards of making certain cross-sex comparisons, and we argue for more caution in their application.  相似文献   
809.
People vary in the extent to which they hold stereotypic beliefs about women. The recently developed Beliefs About Women Scale (BAWS) was used in five investigations to examine the following aspects of people's stereotypic beliefs about women: (Study I) the impact of ethnicity (Hispanics and Anglos) on women's endorsement of traditional beliefs about women; (Study II) the impact of national culture (Mexico and the United States) on women's responses to the BAWS; (Study III) the extent to which U.S. women define women's and men's mental health in terms of stereotypic beliefs about women; (Study IV) the extent to which preferences for counseling orientation influence the beliefs about women attributed to mentally healthy women and men; and (Study V) the impact of national culture (Mexico and the United States) on the beliefs about women ascribed to mentally healthy women and men. The results indicated that (a) U.S. Anglo females disagreed more strongly with traditional beliefs about women than did U.S. Hispanic females; (b) U.S. women expressed greater agreement with traditional stereotypes about women's interpersonal abilities and greater disagreement with traditional stereotypes about women's personal competencies than did women from Mexico; (c) the beliefs about women held by U.S. psychology trainees, and the beliefs about women that they attributed to mentally healthy females, were more nontraditional than those that they attributed to mentally healthy males; (d) particular counseling preferences were associated with the stereotypic beliefs about women that female counseling trainees imputed to mentally healthy males and females; and (e) similarities and differences exist on the beliefs about women that female psychology trainees from the United States and Mexico ascribe to mentally healthy females and males. The discussion focuses on mentally healthy beliefs about women, and the implications of these findings for the delivery of mental health services to women and men from various cultures.  相似文献   
810.
Several theories to account for the origin of tunnel hallucinations and tunnel experiences near death are considered: (1) the idea of a real tunnel; (2) representations of transition; (3) reliving birth memories; (4) imagination; and (5) physiological origins. Three different physiological theories are considered that related the tunnel form to the structure of the visual cortex. All can account for much of the phenomenology of the tunnel experience, and all lead to testable predictions. It is argued that the tunnel experience involves a change in the mental model of the self in the world. Because of this, an experience of purely physiological origin, with no implications for other worlds or for survival, can nevertheless produce lasting changes in the sense of self and reduce the fear of death.  相似文献   
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