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991.
Comprehension of connected language as assessed by the Revised Token Test (RTT) was studied in 17 children with left hemisphere lesions (LL) and 11 with right hemisphere lesions (RL). LL children's significantly lower performance on several subtests than left controls (LC) matched by age, sex, race, and social class appeared to be related to the memory demands of these subtests rather than the limited syntactic elements assessed by the RTT. LL subjects requested significantly more command repetitions than control or RL subjects and when a repetition was not requested LL subjects often responded with immediacy. Although RL children tended to perform lower than right matched controls (RC), these differences were not significant nor readily related to either the memory or specific linguistic structures assessed. RL subjects required fewer command repetitions than LL subjects and exhibited a significantly greater frequency of immediate responses than controls or LL subjects. While based on few children, a trend for LL children with retrorolandic lesions to perform more poorly than those with left prerolandic lesions was suggested. No systematic difference in performance was apparent for children with left cortical vs. left subcortical lesions or among discrete sites of lesions within the right hemisphere. Children with left lesions prior to 1 year of age performed no better and, in several instances, significantly poorer than LL patients sustaining lesions after 1 year of age. Among RL subjects, those sustaining lesions after 1 year of age had greater difficulty than those with lesion onset before 1 year of age, especially on linguistic elements which seemed to be dependent upon visual spatial properties. Further studies are needed to evaluate the comprehension of more complex linguistic structures among children with unilateral brain lesions as well as to study the role of more basic factors such as memory and attention in explaining the present findings. 相似文献
992.
Laurence B. Leonard Letizia Sabbadini Jeanette S. Leonard Virginia Volterra 《Brain and language》1987,32(2):233-252
A common profile in English-speaking specifically language-impaired children is a moderate deficit across a broad range of linguistic features and a more marked, selective impairment in using bound morphemes and components of the verb system. To gain a clearer understanding of the nature of these more serious problems, we examined the speech of monolingual Italian-speaking as well as English-speaking children with specific language impairment. The evidence suggested that phonological factors contributed significantly to these children's extraordinary problems with particular linguistic features. Contrary to expectations, other marked deficits seemed more related to the opacity of the rules involved and homonymity with other morphemes than to problems with formal grammatical devices in general or components of the verb system in particular. 相似文献
993.
994.
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
995.
Charles B. Daniels 《Studia Logica》1987,46(1):73-86
In [2] a semantics for implication is offered that makes use of stories — sets of sentences assembled under various constraints. Sentences are evaluated at an actual world and in each member of a set of stories. A sentence B is true in a story s just when B s. A implies B iff for all stories and the actual world, whenever A is true, B is true. In this article the first-order language of [2] is extended by the addition of the operator the story ... says that ..., as in The story Flashman among the Redskins says that Flashman met Sitting Bull. The resulting language is shown to be sound and complete. 相似文献
996.
997.
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
998.
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
999.
Mary L. Jasnoski David S. Cordray B. Kent Houston Wayne H. Osness 《Motivation and emotion》1987,11(1):1-17
This psychophysiological evaluation of an aerobic exercise program examined specifically whether aerobic training modified Pattern A for those individuals at behavioral risk for developing coronary heart disease, i.e., young Type A individuals. At pretest and posttest of this secondary prevention study, Type A and Type B subjects were assessed in three conditions: aerobic exercise program, nonaerobic activity (Aikido, a martial art) control, and notreatment control. After 10 weeks, Type A but not Type B subjects exhibited lower Pattern A behavior in the aerobic program than in control conditions. Average workout pulse rates and differentially reliable increases in aerobic capacity indicated that aerobic training was indeed aerobic, whereas aikido activity was not. Even though selected nonaerobic factors, such as locus of control and group participation, did not mediate the Pattern A decrease for Type A's when comparing aikido and aerobic conditions, changes in aerobic capacity may have been the mediator. Generalizability of the results and implications for theoretical development and clinical intervention are discussed. 相似文献
1000.
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