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991.
992.
Essential hypertension is a chronic disorder having many potential physical and behavioral sequelae. This article evaluates the impact of hypertension on neuropsychological test performance. First, cross-sectional and longitudinal studies that examine the neuropsychological correlates of hypertension are reviewed. In general, hypertensives are found to perform more poorly than normotensives, particularly on tests of memory, attention, and abstract reasoning, and less consistently on tests of perception, constructional ability, mental flexibility, and psychomotor speed. Next, the influence of variables that may moderate relationships between hypertension and neuropsychological performance--such as age, education, and medication usage--are examined. Finally, potential mechanisms, both physiological and psychological, underlying associations between hypertension and neuropsychological performance are discussed.  相似文献   
993.
Videocassettes have become the dominant medium for pornography. One previous content analysis examined the prevalence of violence in such videos. The Attorney General's Commission on Pornography (1986) has asserted that nonviolent pornography depicting degradation produces harm similar to that from violent pornography. Content analysis of a 10% random sample (n = 50) of the videos displayed in the "adult" section of a video store showed that 13.6% of the scenes in the videos contained violent acts and 18.2% contained degrading acts.  相似文献   
994.
Categories and particulars: prototype effects in estimating spatial location   总被引:12,自引:0,他引:12  
A model of category effects on reports from memory is presented. The model holds that stimuli are represented at 2 levels of detail: a fine-grain value and a category. When memory is inexact but people must report an exact value, they use estimation processes that combine the remembered stimulus value with category information. The proposed estimation processes include truncation at category boundaries and weighting with a central (prototypic) category value. These processes introduce bias in reporting even when memory is unbiased, but nevertheless may improve overall accuracy (by decreasing the variability of reports). Four experiments are presented in which people report the location of a dot in a circle. Subjects spontaneously impose horizontal and vertical boundaries that divide the circle into quadrants. They misplace dots toward a central (prototypic) location in each quadrant, as predicted by the model. The proposed model has broad implications; notably, it has the potential to explain biases of the sort described in psychophysics (contraction bias and the bias captured by Weber's law) as well as symmetries in similarity judgments, without positing distorted representations of physical scales.  相似文献   
995.
This study examined three factors affecting college students' attributions of blame for an AIDS patient's disease: sexual orientation of the patient, mode of HIV transmission, and the sex of the subject. 148 subjects read one of six vignettes describing an hypothetical AIDS patient who was described as either an heterosexual or an homosexual man who contracted HIV through one of three avenues: blood transfusion, sexual contact, or IV drug use. The homosexual AIDS patient was considered more to blame for his illness than the heterosexual AIDS patient, but only when mode of transmission was sexual contact. In addition, mode of HIV transmission was a significant factor in attributions of responsibility, as the patient who contracted HIV through a blood transfusion was rated as less responsible than the patient who contracted HIV through sexual behavior or IV drug use. Women consistently rated the AIDS patient as less responsible than did men.  相似文献   
996.
Some clarifications of the CANDECOMP algorithm applied to INDSCAL   总被引:2,自引:0,他引:2  
Carroll and Chang have claimed that CANDECOMP applied to symmetric matrices yields equivalent coordinate matrices, as needed for INDSCAL. Although this claim has appeared to be valid for all practical purposes, it has gone without a rigorous mathematical footing. The purpose of the present paper is to clarify CANDECOMP in this respect. It is shown that equivalent coordinate matrices are not granted at global minima when the symmetric matrices are not Gramian, or when these matrices are Gramian but the solution not globally optimal.Part of this research has been supported by The Netherlands Organization for Scientific Research (NWO), PSYCHON-grant (560-267-011).  相似文献   
997.
An analysis is provided detailing the conditions for the appropriate theoretical study of the object of educational science: pedagogy.  相似文献   
998.
999.
Treiman (1983) and others have argued that spoken syllables are best characterized not as linear strings of phonemes, but as hierarchically organized units consisting of an onset (initial consonant or consonant cluster) and a rime (the vowel and any following consonants) and that the rime is further divided into a peak or nucleus (the vowel) and a coda (the final consonants). It has also been argued that the sonority (or vowel-likeness) of the consonant closest to the peak, which is a function of its phonetic class, may have an effect on the strength of boundaries determined by the hierarchical division of the syllable (e.g., Treiman, 1984). We examined the evidence for syllable-internal structure and for sonority in two experiments that employed visually presented stimuli and lexical decision, naming, and reading tasks. Our results provide support for the breakdown of the rime into a peak and a coda and for an effect of the sonority of the postvocalic consonant on that break. This pattern occurred only in our lexical decision tasks, so the effect is assumed to be postlexical. We did not find an effect of the onset-rime boundary, perhaps because of an unanticipated effect of word frequency. Our results are discussed in terms of phonological coding in short-term memory.  相似文献   
1000.
The developmental course of rhythmic motor behavior was followed longitudinally for three groups of preambulatory children — normally developing, Down syndrome, and those with profound motor impairment. The groups differed in chronological age but were comparable with respect to motor age. The motor impaired subjects displayed significantly less rhythmic motor behavior than the nondisabled and Down syndrome groups. In comparing particular subtypes of rhythmic motor behavior, differences were found in both the average number of bouts and duration of subtypes among the groups. Longitudinal analyses of the data over the entire observation period revealed that the rhythmic motor behavior of the children with Down syndrome was more similar to that exhibited by the nondisabled children than was the rhythmic motor behavior of the children with motor impairment. However, there was considerable variability among the groups in several particular subtypes.This research was supported by grants from the National Institute of Child Health and Human Development (HD 17650 and HD 07226).The authors acknowledge the assistance of Robert E. Arendt, Grant Youngquist, Michael Hohn, and Charles Lowitzer in obtaining the observational data and thank the families of the subjects for their enthusiasm and dedication to the project.This study was presented at the 23rd Annual Gatlinburg Conference on Research and Theory in Mental Retardation and Developmental Disabilities, April 21, 1990.  相似文献   
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