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91.
Influence of animation on dynamical judgments.   总被引:3,自引:0,他引:3  
The motions of objects in the environment reflect underlying dynamical constraints and regularities. The conditions under which people are sensitive to natural dynamics are considered. In particular, the article considers what determines whether observers can distinguish canonical and anomalous dynamics when viewing ongoing events. The extent to which such perceptual appreciations are integrated with and influence common-sense reasoning about mechanical events is examined. It is concluded that animation evokes accurate dynamical intuitions when there is only 1 dimension of information that is of dynamical relevance. This advantage is lost when the observed motion reflects higher dimension dynamics or when the kinematic information is removed or degraded.  相似文献   
92.
We measured subjective-tone identification thresholds evoked by acoustically filtered complex tones and compared them to Mandarin-Chinese tone-phoneme identification thresholds previously measured under the same filtering conditions. Tone phonemes were identified at intensities below subjective-tone identification thresholds, suggesting subjective tone is not necessary for tone-phoneme identification. Lower subjective-tone thresholds evoked by resolved harmonics rather than unresolved harmonics were consistent with pattern recognition theories of pitch perception.The authors thank Donald Gans and Richard Klich for all their help.  相似文献   
93.
A short-term longitudinal study was conducted to determine whether self-regulation at 4 years could be predicted from child and maternal measures obtained when the children were age 24 months. The subjects were 69 children and their mothers drawn from the general community. Criterion behaviors assessed at 4 years were those suggestive of attention-deficit hyperactivity disorder. Of the 24-month child measures, maternal ratings of the child's impulsivity and attention span, plus an objective measure of delay ability, were the most effective predictors. Maternal negativity, as assessed in mother-child interaction, predicted the criterion behaviors, even after the child's behavior as an elicitor of maternal behavior was controlled. Maternal child-rearing attitudes on the dimensions of warmth and aggravation were also effective predictors, even after controlling for the child's emotionality as a possible determinant of maternal attitudes. It is argued that the results with the maternal attitude measures provide support for the hypothesis that maternal behavior is a contributor to the development of self-regulation.This research was supported by a State of Ohio Academic Challenge Grant to the Bowling Green State University Clinical Psychology Program, and by a Basic Grant awarded to the first author by the Bowling Green State University Faculty Research Committee. The authors are grateful to Eric Dubow, Douglas Ullman, and two anonymous reviewers for their helpful comments and criticisms on previous versions of this article.  相似文献   
94.
Reports that the dihydropyridine Ca2+ channel antagonists may facilitate memory led to the present study of the behavioral effects of nifedipine. Ninety-two 4-day-old male chicks received 0, 100 nM, 100 microM, or 10 mM nifedipine. Drugs were administered in volumes of 2 microliters into the fourth cerebral ventricle 5 min before training on a visual discrimination task. Nifedipine did not produce any detectable changes in behavior during acquisition trials. Retention, however, was impaired 24 h after training in the 100 nM and 100 microM nifedipine-treated chicks, which made significantly more errors than controls. Nifedipine did not affect the amount of time required to complete the task. No effects on body weight gain were detected, suggesting that the memory impairment was not due to a change in feeding behavior. These data are discussed in terms of the role of calcium-dependent processes in memory.  相似文献   
95.
The hypothesis that representation of projective shape is preattentive whereas representation of objective shape in three-dimensional space requires allocation of attention was tested in 2 visual search and 2 precuing experiments. In the visual search experiments, the slope for projective shape search was expected to approach 0 and that for objective shape search was expected to be a positive monotonic function of set size. In the precuing experiments, the effects of precuing were expected to be largely limited to the task requiring representation of objective shape. The overall pattern of results conformed to expectations. The findings are interpreted in the context of a model of shape-at-a-slant processing set out by Epstein and Lovitts (1985) and Epstein and Babler (1989, 1990).  相似文献   
96.
Cerella (1991) has argued that the performance of older adults in the Fisk and Rogers (1991) study is a linear function of the performance of younger adults that is independent of task-specific cognitive requirements. We demonstrate that this is not the case. First, we show that the scatter plot analyses used by Cerella can hide the very task-specific age-related slowing they were designed to reveal. Second, we demonstrate that the percentage of variance explained by such analyses can be misleading. Third, we show that there are reliable differences across tasks in the parameters relating younger and older adults' performance. Finally, we argue that the general, task-independent proportionate slowing that Cerella suggested explains so much of the variance in age-related performance is actually an average slowing that is a function of a relatively small task-independent and a relatively large task-dependent factor.  相似文献   
97.
Little is known about the conditions that encourage animals to learn to use configural associations to guide their behavior or the consequences of such learning for transfer. This study provided some information about these issues by examining how rats solve the transverse-patterning problem, which requires a configural solution (Spence, 1952). Animals had to concurrently solve 3 simultaneous visual discriminations, represented abstractly as A+ versus B-, B+ versus C-, and C+ versus A-. Experiment 1 indicated that rats use a configural solution even when the problems have an elemental solution, provided that the significance of 1 element (e.g., B) shared by 2 problems is ambiguous (e.g., A+/B-; and B+/C-). Experiments 2 and 3 suggested that, when stimulated to use a configural solution by solving the A+/B- and B+/C- problems, rats transfer the configural solution to problems that have no ambiguous elements.  相似文献   
98.
A multivariate hierarchical model of specific cognitive abilities was fitted to data from 7-year-old adopted and nonadopted sibling pairs in the Colorado Adoption Project in order to assess differential genetic influence on specific mental abilities. Model fitting results and Schmid-Leiman (Schmid & Leiman, 1957) transformations reveal significant heritable variation for verbal, spatial, and memory factors independent of general cognitive ability for the eight ability tests examined. In contrast, environmental influences are primarily measure-specific. The results suggest genetic effects in middle childhood that differentially influence mental ability scores.  相似文献   
99.
Reminder treatments have been shown to facilitate the retrieval of a variety of conditioned responses. Whether or not similar results would occur with an experimental paradigm which involves primarily memory for a stimulus, i.e., where no particular response is specified, is unclear. Accordingly, using Sprague-Dawley rats, we employed a latent inhibition paradigm with a long (10 days) retention interval between sucrose (CS) preexposure and sucrose-illness pairing (training). The results demonstrated a loss of latent inhibition following the 10-day retention interval suggesting "forgetting" of the CS preexposure. However, placing a single reminder exposure to the CS within the preexposure-to-training interval reinstated the preexposure effect. Controls indicated that in the absence of the initial preexposure the reminder per se did not produce latent inhibition. Thus, a reminder can reinstate a stimulus attribute (flavor representation) and explicit conditioned responses.  相似文献   
100.
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