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991.
Accelerating self-motion displays produce more compelling vection in depth   总被引:1,自引:0,他引:1  
We examined the vection in depth induced when simulated random self-accelerations (jitter) and periodic self-accelerations (oscillation) were added to radial expanding optic flow (simulating constant-velocity forward self-motion). Contrary to the predictions of sensory-conflict theory frontal-plane jitter and oscillation were both found to significantly decrease the onsets and increase the speeds of vection in depth. Depth jitter and oscillation had lesser, but still significant, effects on the speed of vection in depth. A control experiment demonstrated that adding global perspective motion which simulated a constant-velocity frontal-plane self-motion had no significant effect on vection in depth induced by the radial component of the optic flow. These results are incompatible with the notion that constant-velocity displays produce optimal vection. Rather, they indicate that displays simulating self-acceleration can often produce more compelling experiences of self-motion in depth.  相似文献   
992.
Human spatial representations of object locations in a room-sized environment were probed for evidence that the object locations were encoded relative not just to the observer (egocentrically) but also to each other (allocentrically). Participants learned the locations of 4 objects and then were blindfolded and either (a) underwent a succession of 70 degrees and 200 degrees whole-body rotations or (b) were fully disoriented and then underwent a similar sequence of 70 degrees and 200 degrees rotations. After each rotation, participants pointed to the objects without vision. Analyses of the pointing errors suggest that as participants lost orientation, represented object directions generally "drifted" off of their true directions as an ensemble, not in random, unrelated directions. This is interpreted as evidence that object-to-object (allocentric) relationships play a large part in the human spatial updating system. However, there was also some evidence that represented object directions occasionally drifted off of their true directions independently of one another, suggesting a lack of allocentric influence. Implications regarding the interplay of egocentric and allocentric information are considered.  相似文献   
993.
Typically, the phonological similarity between to-be-recalled items and TBI auditory stimuli has no impact if recall in serial order is required. However, in the present study, the authors have shown that the free recall, but not serial recall, of lists of phonologically related to-be-remembered items was disrupted by an irrelevant sound stream (end rhymes) sharing similar phonological content. These findings can be explained by the notion that between-sequence phonological similarity effects emerge when category-cueing processes become an important determinant for recall, such as when shared category information can be used as a retrieval aid to cue list items or plausible list candidates. In this case, the presence of categorically similar irrelevant items impairs the retrieval of list items and leads to intrusion error. Implications of these results for theories of auditory distraction are discussed.  相似文献   
994.
Verbal fluency tests are useful measures of acquired language impairment and cognitive decline of various etiologies. The aim of this study was to provide normative data for the Swedish population on the three verbal fluency tests, FAS, Animals and Verbs. A group of 165 healthy participants ranging from 16 to 89 years of age were assessed with the verbal fluency tests and tests of level of intellectual functioning. The sample was stratified by education, age and gender. Level of education had a substantial influence on the performance on verbal fluency, most clearly so in FAS and Verbs. Intellectual level had a positive and significant correlation with all measures of word fluency. Moreover, there was an interaction between age and gender such that women aged between 30 and 64 years outperformed elderly men on FAS and Verbs. Guidelines for instructions and scoring in Swedish are given in the article.  相似文献   
995.
Two basic approaches to explaining the nature of the mind are the rational and the mechanistic approaches. Rational analyses attempt to characterize the environment and the behavioral outcomes that humans seek to optimize, whereas mechanistic models attempt to simulate human behavior using processes and representations analogous to those used by humans. We compared these approaches with regard to their accounts of how humans learn the variability of categories. The mechanistic model departs in subtle ways from rational principles. In particular, the mechanistic model incrementally updates its estimates of category means and variances through error-driven learning, based on discrepancies between new category members and the current representation of each category. The model yields a prediction, which we verify, regarding the effects of order manipulations that the rational approach does not anticipate. Although both rational and mechanistic models can successfully postdict known findings, we suggest that psychological advances are driven primarily by consideration of process and representation and that rational accounts trail these breakthroughs.  相似文献   
996.
The research reported in the present article investigates whether information is represented the same way in both visual mental imagery and the early phases of visual perception. In Experiment 1, the same participants scanned over patterns of dots in a mental image (with images based on a just-seen pattern), during perception, and in an iconic image. The time to scan increasing distances increased at comparable rates in the three tasks. However, in Experiment 2, when mental images were created from information stored in long-term memory, participants scanned more slowly in the mental image condition. Nevertheless, the rates of scanning in the perceptual tasks were highly correlated with the rates of scanning in the imagery tasks in both experiments. The results provide evidence that mental images and perceived stimuli are represented similarly and can be processed in the same way.  相似文献   
997.
Neo-Darwinian theories of religion include both nonadaptationist and adaptationist versions. Nonadaptationist versions contend that the mental architecture of the brain is wired for religious thinking but that religious concepts have piggybacked on other cognitive adaptations, especially those for agency detection. Religious concepts are not evolved biological adaptations but rather by-products of more general cognitive structures that are adaptations. Adaptationist versions concentrate on the benefits provided by religion, such as increased social cohesion and the individual benefits that stem from it, such as better physical and mental health and greater longevity. After clarifying the meaning of the terms “adaptation” and “adaptationism,” this article presents four lines of evidence in favor of the adaptationist position: (1) in the ancestral environment the role of the shaman was nearly universal and was primarily devoted to the crucial human goals of curing illness and protecting and finding vital resources; (2) religion generally has positive effects on both physical and mental health; (3) religions tend to be pro-natalist and more religious people tend to leave more offspring than less religious or nonreligious people; (4) the major world religions that evolved in the first millennium BCE during a period of major social chaos and disruption emphasized an omnipotent, transcendent God of love and mercy who offered salvation in a heavenly afterlife and released individuals from earthly suffering. None of these facts demonstrate conclusively that cognitive modules specifically oriented to supernatural agents evolved by natural selection, but they are highly suggestive and make a good inferential case.  相似文献   
998.
Community coalitions represent a promising approach for addressing the interrelated and multiply- determined issues affecting urban neighborhoods of concentrated poverty. The literature suggests a number of community processes that may affect coalition efforts to change and improve communities. This study uses an interrupted time-series design to examine the effects of a strategic planning intervention on community change in two urban neighborhoods in the Kansas City metropolitan area. Results showed that strategic planning was associated with increased rates of community change in the two urban neighborhood coalitions. Under appropriate conditions, such as the presence of consistent leadership, strategic planning may be a particularly effective mechanism for stimulating community change and addressing locally-determined goals in urban neighborhoods.  相似文献   
999.
To estimate the prevalence of being well-adjusted in adolescence, boys and girls with (n = 96) and without (n = 126) attention-deficit/hyperactivity disorder (ADHD) were assessed seven times in eight years starting when they were 4–6 years of age. Symptoms of ADHD, ODD/CD, and depression/anxiety in addition to social skills and social preference were gathered using multiple methods and informants. Being well-adjusted was defined by surpassing thresholds in at least four of the five domains. At the 7- and 8-year follow-up, when youth were 11–14 years old, probands were significantly less likely to be well-adjusted relative to age- and ethnicity-matched control children. Only a minority of children with ADHD was well-adjusted in adolescence when emotional, behavioral, and social domains were considered simultaneously. Even when their ADHD symptoms improved over time, most probands exhibited significant impairment 7–8 years after their initial assessment.  相似文献   
1000.
This study examines the role of personality in predicting psychological and physical health among grandmothers who are coping with a non-normative non-traumatic stressor, i.e. serving as primary caregivers for their grandchildren. Using the Life Orientation Test-Revised (LOT-R), a measure of personality disposition, we examine the contributions of both optimism and pessimism to health outcomes. ANOVAs and regression analyses of the LOT-R and self reports of health in 67 African American and Latino grandmothers revealed psychological (obsessive compulsive symptoms, depression, hostility) and physical (sleep disorder, hypertension) health outcomes are differentially predicted by optimism and pessimism among older and younger age-groups of grandmothers. Implications for grandmothers’ response to caregiving stress and for future studies of personality’s relation to health are discussed.  相似文献   
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