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971.
Electroencephalographically oriented research on vigilance needs valid measures for assessing the level of vigilance between wakefulness and sleep. When studying different psychologically, psychopathologically, and pharmacologically induced states, special attention has to be paid to minor alterations of the level of vigilance which are reflected, essentially, in topographical changes of alpha-activity (Stage A). Since vigilance is a dynamic process, brief fluctuations in the range of a few seconds must also be recorded. In our opinion existing methods of quantification do not fully meet these demands. We have, therefore, developed a relatively simple procedure which can be characterized as an attempt quantitatively to reconstruct visually, i.e., spatiotemporally defined patterns of vigilance. The usefulness of this method, which also has certain limitations, has been demonstrated in psychopharmacological studies.  相似文献   
972.
9 stutterers and 9 nonstutterers were administered a dichotic digits test under conditions of free recall and directed attention. Analysis indicated right-ear preference for both groups and no differences between the free recall and directed listening conditions. Results are discussed in relation to previous studies in which dichotic digit-stimuli were presented to stutterers.  相似文献   
973.
6 adult subjects (3 men, 3 women) produced highly similar spontaneous speech utterances in quiet and with 90-dB SPL white noise. The frequency of occurrence of perceptual judgments of primary stressing in an utterance was not affected by the masking noise. This finding supplements our previous report that variability for stress production of fundamental frequency (fo) during spontaneous speech was preserved under short-term auditory disruption. Also, it adds further support to the contention that fo is under open-loop regulation.  相似文献   
974.
Children's perception of parental exercise: influence of sex and age   总被引:1,自引:0,他引:1  
The purpose of the study was to document children's perception of parental exercise, relating these perceptions to (1) the self-reported parents' habits of exercise, and (2) the children's own activity patterns. The subjects were 198 students of both sexes, aged 12 to 14 yr. and enrolled in school Grades 7 to 9. A standard questionnaire assessed their perceptions of parental and personal physical activity. Both parents of each subject also reported their respective levels of habitual physical activity. Congruence between the children's perceptions and the self-reported exercise habits of the opposite-sex parent differed for boys and girls, increasing for boys and decreasing for girls between Grades 7 and 9. No significant associations were observed between the children's perception of parental exercise patterns and their own like habits. This suggests that during adolescence parental influences are minimized by other factors, personal or environmental.  相似文献   
975.
A task requiring the mental rotation of letters was performed either alone or during the retention interval of two short-term memory tasks. The retention of eight digits or random configurations of eight dots slowed overall reaction time on the mental-rotation task, but did not significantly alter the estimated rate of mental rotation. Conversely, performance on the memory tasks did not vary with the angle of mental rotation. These results support the view that attentional control is required to set up the mental structures required in mental rotation, but that the actual execution of the mental-rotation component can be relegated to subordinate systems that do not compete for attentional resources.  相似文献   
976.
In two experiments, we investigated the factors that influence the perceived similarity of speech sounds at two developmental levels. Kindergartners and second graders were asked to classify nonsense words, which were related by syllable and phoneme correspondences. The results support the existence of a developmental trend toward increased attention to individual phonemic segments. Moreover, one significant factor in determining the perceived similarity of speech sounds appears to be the position of the component correspondences; attention to the beginning of utterances may have developmental priority. An unexpected finding was that the linguistic status of the unit involved in a correspondence (whether it was a syllable or a phoneme) did not seem particularly important. Apparently, the factors which contribute to the perceived similarity of speech sounds in the classification task are not identical to those which underlie performance in explicit segmentation and manipulation tasks, since in the latter sort of task, syllables are more accessible than phonemes for young children. The present task may tap a level of processing that is closer to the one entailed in word recognition and lexical access.  相似文献   
977.
The lexical decision task has been employed to investigate the effects of semantic context on word recognition. A frequent finding from the task is that “word” responses are slower when the target is preceded by an unrelated word than when it is preceded by a neutral stimulus. This inhibition effect has been interpreted as indicating that the unrelated prime interferes with word-recognition processes operating on the target. In three experiments, the effects of unrelated primes were compared for a lexical decision and word naming task. Although large inhibition effects were found for the lexical decision task in all experiments, no inhibition effects were observed for the naming task. The results are interpreted as demonstrating that inhibition effects in the lexical decision task are not on recognition processes; rather they are located at processes operating after recognition of the target has occurred.  相似文献   
978.
To investigate the properties that make a word easy to recall, we added to existing norms for 925 nouns measures of availability, goodness, emotionality, pronunciability, and probability of recall in multiple-trial free recall. Availability, imagery, and emotionality were found to be the best predictors of which words were recalled. This result, which is stable across recall data collected in three separate laboratories, argues for the importance of availability as a predictor of recall and questions the role of the correlated variables of word frequency and meaningfulness. Consistent with earlier work on a smaller sample of words, six factors describe the numerous properties of words studied by psychologists. The six factors are composed of variables based on orthography, imagery and meaning, word frequency, recall, emotionality, and goodness.  相似文献   
979.
Punctuation in 20 radio homilies by four speakers accounted for 76% of pause time and 64% of pause number. Pause duration varied systematically according to punctuation type. Commas accounted for 82% of punctuated positionsnot used for pausing.RRelevance for theories of text unitization is discussed. Both typographical and temporal measures are compared with a similar corpus of German homilies.  相似文献   
980.
Santosh C. Panda 《Synthese》1986,67(2):259-271
The axioms adopted by Packard (1981) and Heiner and Packard (1983) for plausibility ranking of sets of statements are critically examined. It is shown that the informational requirement of the Heiner-Packard (1983) framework is much stronger than Packard's (1981) framework and hence both axiomatic setups are examined separately. A characterization of the leximin rule is provided in Packard's framework and the nonintuitive implications of the Heiner-Packard (1983) axioms are discussed. It is also demonstrated that in both frameworks, minor variations of some of the axioms convert the characterization results into logical impossibilities.I am grateful to Prof. P. K. Pattanaik for many helpful suggestions.  相似文献   
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