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201.
In comparison to younger adults, older adults demonstrate deficiencies in cognitive and linguistic abilities. Such cognitive factors that decline with age include working memory capacity and inhibitory abilities. The purpose of the present investigation was to measure differences in time course processing of inference revision abilities, as well as working memory, as they exist relative to adult age differences. Fifteen neurologically intact older adults and 15 younger adults participated in this study. A cross-modal lexical priming paradigm was chosen as the measure of the inference revision task; the listening span task of Tompkins, Bloise, Timko, and Baumgaertner (1994) was selected as the measure of working memory. Both groups demonstrated normal priming effects. No age-related differences were found on the working memory measure. Age-related differences did emerge on inferencing abilities. A significant correlation emerged between the older group's performance on comprehending inference revisions and their working memory capacity. Generally, inhibitory abilities and working memory capacity appeared to adversely affect older participant's performance. 相似文献
202.
Drake RA 《Brain and cognition》2002,50(1):17-24
Converging evidence supports a left hemisphere role in defensive repression and sensation seeking. This led to the hypothesis that students with a relatively active left hemisphere would perform poorly during 8 weeks of a college class. The measure of relative hemispheric activation was the visual line-bisecting task given early in the course. The hypothesis was supported. Previous evidence that activation asymmetry is stable over time was supported because the single measurement of line bisecting was a longitudinal predictor of multiple behaviors. A temporal pattern of increasing correlation between the bisecting and performance measures favors a feedback repression model. Alternative explanations based on sensation seeking, subject-matter repression, and cooperation were considered but not eliminated. 相似文献
203.
In the first part of this paper we review evidence suggesting that there exists a mechanism that selects input on the basis of its similarity to the required action. This response-based input selection differs from the more established space- and object-based input selection in that it is not constrained by the structure of the input. Our evidence suggests that the two-choice Stroop effect is caused by this response-based selection mechanism. By contrast, it is known that the flanker effect is determined by the space- and object- based selection mechanisms. We explore whether the conflict resolution of the Stroop and flanker tasks is different as well by embedding these two tasks in a PRP (Psychological Refractory Period) paradigm. We show that the Stroop and the PRP effects are additive whereas the flanker and the PRP effects are underadditive, suggesting that the processes in charge of the conflict resolution in the Stroop and the flanker tasks are indeed different. We discuss possible reasons for this difference, and discuss possible ways in which the response-based mechanism can be implemented in information processing models. 相似文献
204.
George W. Harris 《Ethical Theory and Moral Practice》2002,5(3):271-286
The problem of pessimism is the secular analogue to the evidential problem of evil facing traditional theism. The traditional theist must argue two things: that the evidence shows that this is on balance a good world and that it is the best possible world. Though the secular optimist who advocates any form of secular moral theory need not argue that the current and future world will likely be the best possible world, she nonetheless must argue that were there a clean solution to the problem of current and future suffering in which all sentient life could be instantly and painlessly eliminated, we would have reasons not to employ the clean solution because the future promises to bring on balance a good world in which the evil of human and animal suffering is outweighed by whatever is good in the world. Pessimism is the view that the evidence argues against secular optimism. It is argued here that it is anything but clear that secular optimism is warranted when viewed from an impersonal point of view. The problem is then evaluated from the personal point of view in which a form of personal optimism is defended even in the face of impersonal pessimism. 相似文献
205.
Numerous previous investigators have explained species differences in spatial memory performance in terms of differences
in foraging ecology. In three experiments we attempted to extend these findings by examining the extent to which the spatial
memory performance of echidnas (or "spiny anteaters") can be understood in terms of the spatio-temporal distribution of their
prey (ants and termites). This is a species and a foraging situation that have not been examined in this way before. Echidnas
were better able to learn to avoid a previously rewarding location (to "win-shift") than to learn to return to a previously
rewarding location (to "win-stay"), at short retention intervals, but were unable to learn either of these strategies at retention
intervals of 90 min. The short retention interval results support the ecological hypothesis, but the long retention interval
results do not.
Electronic Publication 相似文献
206.
The purpose of the current study was to determine whether a standardized peer entry paradigm would produce stress responses in 3- and 4-year-olds and how such stress responses would relate to temperament, observed approach to peers, and self-perceived peer competence. Physiological stress reactions were measured by activity of the hypothalamic-pituitary-adrenal (HPA) system. The 4-year-old group showed significantly less avoidance of the new peers and was rated higher on approach temperament. This older group also showed larger HPA stress responses to the new peer situation. Finally, discrepancy between self-reported peer competence and behavior in the peer entry situation was associated with larger stress responses on average. These findings support the notion that investment in a salient episode plays a role in determining the magnitude of HPA stress responses. The importance of examining discrepancies between self-perception and action in research on stress is discussed. 相似文献
207.
The counter model for word identification (Ratcliff & McKoon, 1997) has been challenged by recent empirical findings that performance on low-frequency words improves as the result of repetition of the words. We show that the model can accommodate this learning effect, and that it can do so without jeopardizing its explanations of the effects on word identification of a large number of other variables. 相似文献
208.
Five hundred one right-handers (150 men, 351 women) and 53 left-handers (15 men, 38 women) were asked to imagine holding a young infant in their arms. Right-handers reported significant left-side biases--in 68% of the men and 73% of the women. For left-handers, side preferences were weaker, the left-side bias dropping to 47% for men and 60% for women, with neither figure different from chance. The results are discussed in the context of theory and research on the functional neuroanatomy of attention, emotional arousal, and the generation, maintenance, and manipulation of mental images. 相似文献
209.
Comparing contrast-modulated and luminance-modulated masking: effects of spatial frequency and phase
The masking of a sinusoidal test grating by contrast-modulated (CM) gratings could, in principle, be attributable to the presence of a distortion product, injected into the stimulus during some nonlinear transformation at an early level of visual processing (e.g. Nachmias, 1989 Vision Research 29 137-142). If so, CM gratings and luminance-modulated (LM) gratings of similar effective contrast and spatial frequency should mask the detection of sinusoids in a similar fashion. We compared the effects of masking by 1 cycle deg-1 CM gratings [both simple beats (8 + 9 cycles deg-1) and amplitude-modulated gratings (8 + 9 + 10 cycles deg-1)], with those of masking by 1 cycle deg-1 LM gratings of low contrast. We found that: (i) CM and low-contrast LM grating masks yielded similar spatial-frequency tuning functions around the modulation frequency of 1 cycle deg-1; (ii) low-contrast LM gratings masked the detection of test sinusoids in a highly phase-dependent fashion, while masking by CM gratings did not vary systematically with relative spatial phase. The results suggest that masking produced by CM gratings cannot simply be explained by the presence of a distortion product at the beat or modulation frequency. 相似文献
210.
Robert E. Lee Kathleen Burns Jager Jason B. Whiting Catherine T. Kwantes 《Contemporary Family Therapy》2000,22(1):81-90
Confirmatory factor analysis and regression analyses of the Beavers Interactional Scales did not appear to support the model offered by its developers, namely, several specified family attributes contributing respectively to two global factors of Family Competence and Family Style. Moreover, regression analysis indicated that only three of 12 items predicted raters' assessments of Global Family Health, and one of seven items predicted Global Family Style. Individuals interested in the family dynamic centripetal/centrifugal might best think of that as a unitary entity and rate it accordingly. 相似文献