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981.
Vladimir A. Smirnov 《Studia Logica》1987,46(1):1-15
There is given the proof of strict embedding of Leniewski's elementary ontology into monadic second-order calculus of predicates providing a formalization of the class of all formulas valid in all domains (including the empty one). The elementary ontology with the axiom S (S S) is strictly embeddable into monadic second-order calculus of predicates which provides a formalization of the classes of all formulas valid in all non-empty domains. 相似文献
982.
Regional cerebral blood flow (rCBF) may be measured with inhalation techniques that use end-expired values of radioactivity to estimate the isotope concentration in arterial blood. These end-expired data are used as an input function in a mathematical equation to derive rCBF. End-expired air is assumed normally to be in equilibrium with the arterial blood at the alveolar surface of the lung during regular (passive) breathing; this assumption may not be valid during continuous phonation. We therefore have analyzed breathing (inhalation/exhalation) patterns and end-expired radioactivity (133Xe) during (1) speaking, (2) singing, and (3) humming of the national anthem, and also during (4) passive breathing. Statistically significant differences in breathing patterns were measured between a group of nonmusicians and two groups of musicians (singers) during the phonation tasks: The nonmusicians breathed more often (and more rapidly) and exhibited less variability in their breathing patterns than did the musicians. Notwithstanding these differences, the shapes of smoothed functions derived from the end-expired values were not influenced appreciably during phonation (except possibly during talking). The latter finding suggests that estimates of rCBF derived with these data should not be confounded seriously because of the continuous phonation. 相似文献
983.
Lori A. McElroy 《Memory & cognition》1987,15(2):148-153
The generation effect is the phenomenon in which words are remembered better when generated than when read. These experiments test the possibility that at least one consequence of generating is enhanced semantic processing. Homographs were used as targets, presented with rhymes in Experiment 1 so as not to bias meaning, and with synonyms in Experiment 2 to bias one meaning of each homograph. In beth experiments, extralist synonym cues were provided at recall. In Experiment 1 a generation effect was obtained when the retrieval cues biased the dominant meaning of the homograph (determined from free association norms), whereas in Experiment 2 a generation effect was found when the retrieval cues biased the same meaning that was biased during study. In neither experiment was a generation effect obtained with retrieval cues that biased the other meaning of each homograph. These results indicate that the generation effect is dependent upon the compatibility of the semantic processing conducted at study and test. Since it is impossible to process the meaning of a homograph when generating it from a rhyme cue, the meaning of the homograph could only have been processed after the word had been generated. The finding in Experiment 1 that a generation effect was obtained with rhymes when semantic retrieval cues were provided demonstrates that the enhancement properties associated with generation are not restricted to the information used to guide the generation process. This finding also indicates that one locus of the generation effect is in the processing that occurs after the word has been generated. 相似文献
984.
985.
The ability of prelingually, profoundly deaf readers to access phonological information during reading was investigated in three experiments. The experiments employed a task, developed by Meyer, Schvaneveldt, and Ruddy (1974), in which lexical decision response times (RTs) to orthographically similar rhyming (e.g., WAVE-SAVE) and nortrhyming (e.g., HAVE-CAVE) word pairs were compared with RTs to orthographically and phonologically dissimilar control word pairs. The subjects of the study were deaf college students and hearing college students. In Experiments 1 and 2, in which the nonwords were pronounceable, the deaf subjects, like the hearing subjects, were facilitated in their RTs to rhyming pairs, but not to nonrhyming pairs. In Experiment 3, in which the nonwords were unpronounceable, both deaf and hearing subjects were facilitated in their RTs to both rhyming and nonrhyming pairs, with the facilitation being significantly greater for the rhyming pairs. These results indicate that access to phonological information is possible despite prelingual and profound hearing impairment. As such, they run counter to claims that deaf individuals are limited to the use of visual strategies in reading. Given the impoverished auditory, experience of such readers, these results suggest that the use of phonological information need not be tied to the auditory modality. 相似文献
986.
Kevin C. Mooney Robert Thompson James M. Nelson 《Journal of abnormal child psychology》1987,15(1):67-73
The relationship between risk factors and the severity and type of childhood disorder, as measured by parent-completed Child Behavior Checklists, was examined for 768 children, ages 4–16, seen at a child mental health center. Regression analyses revealed no significant relationships between any combination of risk factors and the total number of behavior problems, internalizing, or externalizing scores for the entire group, males and females separately, or for the age and sex groupings of 6- to 11- and 12-to 16-yearolds. Chi-square tests revealed no relationship of profile type with any risk factor or with total number of risk factors. Implications for broad-based child assessment and risk factor research within a clinical population are discussed.We wish to thank Orin Bolstad, Linda Magnuson, and Julian Taplin for their assistance in this project. 相似文献
987.
The functional development of cardiac and adrenal medullary responses to reflex activation of the sympathetic nervous system was studied in preweanling spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) normotensive rats. Pups of the two strains received injections of insulin or saline at 2, 4, 8, 12, or 16 days of age and were sacrificed 3 h later. Insulin administration produces a significant decrease in circulating levels of glucose which in turn results in a centrally mediated increase in sympathetic outflow. The induction of ornithine decarboxylase (ODC) in heart and the depletion of epinephrine from the adrenal medulla served as tissue markers of functional sympathetic neurotransmission. WKY and SHR pups had comparable levels of ODC activity in heart under basal conditions. In contrast, levels of catecholamines in the adrenals were greater in SHR pups at 2 and 4 days of age. Following insulin administration, SHR pups exhibited a greater induction of cardiac ODC activity at 2, 4, and 8 days of age compared to age-matched WKY controls. However, there were no differences between SHR and WKY pups in the magnitude of the adrenal medullary response to insulin-induced hypoglycemia. These alterations in sympathetic-target tissue development during the first postnatal week of life may contribute in part to the higher arterial pressures maintained by SHRs throughout the lifespan. 相似文献
988.
Higher levels of affiliation motivation after exposure to affiliative films are significantly related to higher dopamine concentrations in saliva in one study of 61 college students of both sexes, and in plasma in another study of 47 adults of both sexes. Individuals high in dispositionaln Affiliation, if they also reported high life stress, showed high gains in dopamine concentration in plasma after exposure to an affiliative film significantly more often than other individuals. Since aroused affiliation motivation was not associated with higher concentrations of norepinephrine, epinephrine, or cortisol in either study, it appears likely that dopamine is especially associated with arousal of affiliation motivation, just as norepinephrine has been found to be associated with arousal of power motivation. Thus, different motives may be subserved by different hormones, making it unlikely that all motives lead to the same state of physiological arousal.This research was carried out when all the authors were connected with the Department of Psychology and Social Relations at Harvard University. We acknowledge with thanks the support of the John D. and Catherine T. MacArthur Foundation through a grant to the senior author. 相似文献
989.
Individual differences in cognitive arithmetic 总被引:2,自引:0,他引:2
Unities in the processes involved in solving arithmetic problems of varying operations have been suggested by studies that have used both factor-analytic and information-processing methods. We designed the present study to investigate the convergence of mental processes assessed by paper-and-pencil measures defining the Numerical Facility factor and component processes for cognitive arithmetic identified by using chronometric techniques. A sample of 100 undergraduate students responded to 320 arithmetic problems in a true-false reaction-time (RT) verification paradigm and were administered a battery of ability measures spanning Numerical Facility, Perceptual Speed, and Spatial Relations factors. The 320 cognitive arithmetic problems comprised 80 problems of each of four types: simple addition, complex addition, simple multiplication, and complex multiplication. The information-processing results indicated that regression models that included a structural variable consistent with memory network retrieval of arithmetic facts were the best predictors of RT to each of the four types of arithmetic problems. The results also verified the effects of other elementary processes that are involved in the mental solving of arithmetic problems, including encoding of single digits and carrying to the next column for complex problems. The relation between process components and ability measures was examined by means of structural equation modeling. The final structural model revealed a strong direct relation between a factor subsuming efficiency of retrieval of arithmetic facts and of executing the carry operation and the traditional Numerical Facility factor. Furthermore, a moderate direct relation between a factor subsuming speed of encoding digits and decision and response times and the traditional Perceptual Speed factor was also found. No relation between structural variables representing cognitive arithmetic component processes and ability measures spanning the Spatial Relations factor was found. Results of the structural modeling support the conclusion that information retrieval from a network of arithmetic facts and execution of the carry operation are elementary component processes involved uniquely in the mental solving of arithmetic problems. Furthermore, individual differences in the speed of executing these two elementary component processes appear to underlie individual differences on ability measures that traditionally span the Numerical Facility factor.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
990.
Structure and process in semantic memory: new evidence based on speed-accuracy decomposition 总被引:1,自引:0,他引:1
Reaction-time and accuracy data obtained from studies of sentence verification have not been rich enough to answer certain important theoretical questions about structures and processes in human semantic memory. However, a new technique called speed-accuracy decomposition (Meyer, Irwin, Osman, & Kounios, 1986) may help solve this problem. The technique allows intermediate products of sentence verification to be analyzed more precisely. Three experiments with speed-accuracy decomposition indicate that verification processes produce useful partial information before they are completed. Such information appears to accumulate continuously at a rate whose magnitude depends on the degree of relatedness between semantic categories. This outcome is consistent with continuous computational (e.g., semantic-feature comparison) models of semantic memory. An analysis of reaction-time minima suggests that a discrete all-or-none search process may also contribute at least occasionally to sentence verification. Further details regarding the nature of these processes and the memory structures on which they operate can be inferred from additional results obtained through speed-accuracy decomposition. 相似文献