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91.
The authors used a correlated motion paradigm to investigate the effects of aging and gender on motion sensitivity. In 2 experiments with a total of 50 elderly and 50 young subjects, motion thresholds were significantly higher for elderly women. The correlated motion signal, which was embedded in random motion, may have been coherent to subjects in much the same way a form is in Witkin's Embedded Figures Test (EFT). In Experiment 2, EFT scores were obtained. A significant positive relationship between motion thresholds and EFT performance was found within each age group. Although gender-related perceptual style differences may contribute to motion perception effects, the authors argue that a common neural factor contributes to performance on both the EFT and the correlated motion task.  相似文献   
92.
Counselors' vulnerability to inferential bias during the counseling process may result in misdiagnosis and improper interventions. This article provides readers with information regarding inferential bias. The inferential biases discussed include (a) availability and representativeness heuristics; (b) fundamental attribution error; (c) anchoring, prior knowledge, and labeling; (d) confirmatory hypothesis testing; and (e) reconstructive memory. Each bias is described and illustrated through fictitious case vignettes, and suggestions concerning what precautions counselors may do to avoid each type of bias are presented.  相似文献   
93.
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   
94.
This study investigated the relationship between intergenerational family relationships and Frankl's concept of meaning in life. Intergenerational family relationships were measured by the Personal Authority in the Family System Questionnaire (PAFS-QE) by Bray, Williamson, and Malone. The meaning in life variables were measured by the Life Attitude Profile-Revised (LAP-R) by Reker. This quantitative study, using the BMDP Statistical Package (Dixon, 1990), correlated the scores on various subscales from both instruments, resulting in seven statistically significant relationships. The findings, although modest, suggest the existence of a relationship between these two theoretical areas.This article is based in part on the first author's doctoral dissertation at Texas Woman's University.A copy of the PAFS-Q may be obtained from: James H. Bray, PhD, 5510 Greenbriar, Houston, TX 77005. A copy of the LAP-R may be obtained from: Gary Reker, PhD, Trent University, Psychology Department, Peterborough, Ontario Canada K9J 7B8.  相似文献   
95.
This study of 20 ‘white-collar’ workers aged 20–30 measured motivation, enjoyment and access to various categories of experience in both work and leisure, and examined their relationship with psychological well-being on a number of dimensions. The method used a short questionnaire, psychological scales and the innovatory ‘experience sampling methodology’ (ESM) where respondents answer questions in a diary on the receipt of a signal from a pre-programmed watch or radio pager eight times a day for 1 week. The results show, in line with other studies, that intrinsic motivation in daily life is correlated with happiness but that, not previously reported, when motivation at work is examined both extrinsic motivation and instances where a person had to do the activity but did not wish to be doing something else, i.e. ‘positive motivational change’, are correlated with positive aspects of psychological well-being, while instances where a person wanted to do the activity but wished to be doing something else, i.e. ‘negative motivational change’, correlated with negative aspects. The results also show that enjoyment in both work and leisure correlates with aspects of psychological wellbeing; and that macro ‘flow’ experiences, where high skills and high challenges are perceived as equal, are enjoyable and interesting and come primarily from work. The study also shows that categories of experience considered important for psychological well-being and deemed to come primarily from work can be obtained in leisure. The results are discussed in the context of person—situation interactions and processes, and it is advocated that these should be studied in a variety of samples.  相似文献   
96.
Three commentaries are offered on the following case: George, age 57, is a previously healthy man who recently underwent surgery for removal of a low-grade malignant thymoma. At the time of admission to the hospital, George stressed to the staff that he had long ago signed a "living will," which he renewed immediately after he learned of his cancer diagnosis. At the time of surgery, the tumor was found to extend into his mediastinum; although it was removable, this required revision of part of the sternum and grafting of the vessels feeding the heart chambers. Because of the resultant tissue damage and neuronal hyperactivity, George experienced postoperative episodes of cardiac arrhythmia and bronchospasm. Unanimous medical opinion was that this situation was a temporary problem that would resolve itself as the tissues healed. Until that time, however, it will be difficult to wean him from ventilatory support. When his stay in the intensive care unit became prolonged, George and his family began to insist that his status be changed to "do not resuscitate" and reminded the staff about his longstanding living will. All of this is happening despite the fact that the patient and family seemingly comprehend that although the short-term interventions are invasive, there is a high probability of a successful outcome. George's cancer prognosis is excellent, and, although he may well have an episode of life-threatening arrhythmia, he is likely to respond to resuscitation interventions. Once the immediate postoperative period is over, his potential for a long and productive life with full capacities is excellent. Consider the following questions: (a) Should George's expressed wishes be respected, or should the staff take additional steps to help him survive the postoperative period, even if that means violating his stated wishes? and (b) What steps might the staff follow in sorting through this problem?  相似文献   
97.
We examined whether the orientation-contingent color aftereffect (the McCollough effect) could be mediated by subjective horizontal and vertical structure induced by the perception of transparency. In our experiments, red vertical bars and green horizontal bars were alternated as an adapting stimulus. After adaptation, subjects (n=6) were asked to adjust the green and red saturation of a test pattern until they obtained a neutral gray. Horizontal and vertical stripes were combined in the test pattern in three different ways: (1) overlapping with a luminance combination that gave rise to a perception of transparent overlays of horizontal and vertical stripes (valid transparency condition), (2) overlapping with luminance combinations that did not induce a perception of transparency (invalid transparency condition) and that appeased more as a patchwork of checks, and (3) presented in adjacent, nonoverlapping areas. Our results showed that the McCollough effect was significantly greater in the valid transparency condition than in the invalid transparency conditions. The effect in the valid transparency condition was nevertheless less strong than was the effect seen with the standard test stimulus made up of nonoverlapping vertical and horizontal stripes, Our results suggest that the McCollough effect can be mediated by the subjective spatial organization (inner representation of vertical and horizontal stripes) that accompanies the perception of transparency in our stimulus.  相似文献   
98.
The caudal portion of the hypoglossal nucleus (nXIIts) contains the motor neurons that control the syrinx in songbirds. In canaries, song occurs seasonally, is principally produced by males, and appears to be produced predominantly by muscles on the left side of the syrinx. The present study measures the effect of seasonal change and manipulation of testosterone levels on synapse number and morphology in nXIIts in adult female canaries. We find that synapse density is lower in testosterone-treated birds than in control birds and lower in fall than in spring. The number of vesicles per presynaptic profile increases in the spring as a result of a general increase in this measure in all synapses. The number of vesicles per presynaptic profile also increases with testosterone treatment, primarily due to an increase in the proportion of synapses associated with unusually high vesicle counts. Together, these changes suggest that large reserves of neurotransmitter may be necessary to sustain singing. Several ultrastructural differences between hemispheres are found. Postsynaptic thickenings are longer, and postsynaptic processes are larger on the left side than on the right side. In the spring, there are more vesicles per synapse on the left than on the right, but this lateralization is reversed in the fall. Thus, lateralization of song production is associated with lateral asymmetries in synapse morphology. These hemispheric differences are relatively small, like those seen at the light microscope level, encouraging further consideration of peripheral as well as CNS sources of functional lateralization. The seasonal and testosterone-induced changes in synapse number and morphology may be components of the periodic reorganization of canary vocalization.  相似文献   
99.
This study examined the relations among physical fitness, body image, and locus of control. The Hall-Physical Fitness Test Profile, the Winstead and Cash Body Self-relations Questionnaire (BSRQ) and the Nowicki-Strickland Locus of Control Scale were administered to 243 freshmen. Women were significantly more positive about their physical appearance than men. Men were more positive about their physical fitness than women. Men were more physically fit than women. Men and women scoring in the internal direction viewed the physical fitness domain of their body image positively. Unlike men, internally oriented women had more positive perceptions of the health aspect of their body image. Physically fit men and women had positive attitudes toward the physical fitness component of their body image. Physically fit men differed from physically fit women in that men were more internal and held more positive attitudes toward the physical health dimension of their body images.  相似文献   
100.
This study compared normal developing children, aged 34 to 51 mo., on comprehension and production of relative dimensional adjectives using object manipulations in a close elicitation procedure and on Piagetian operational tests of conservation of continuous quantity, length, reversibility and seriation. Analysis indicated a significant difference on the expressive language performance of the transitional and the concrete operational children over the preoperational children, but no significant differences occurred between the first two groups. Children who performed better on seriation were significantly better on expressive language performance. Children classified as operational for length performed better on all language measures than those classified as nonoperational. Reversibility and conservation of a continuous quantity did not differentiate children.  相似文献   
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