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991.
This study examines the effect of different behavioral conditions on patterns of correlation between regional cerebral metabolic rates for glucose. Cerebral glucose metabolism was determined with positron emission tomography and (11C)-deoxyglucose in 29 normal subjects between the ages of 23 and 55. Seventeen subjects were studied in an unstimulated (resting) condition and 12 subjects during a phoneme monitoring language stimulation. Partial correlation coefficients, controlling for whole brain glucose metabolism, were calculated for pairs of metabolic rates in 14 cortical and 2 subcortical regions. Both stimulated and unstimulated subjects showed statistically significant correlations between left and right hemisphere homologs. The stimulated subjects also showed significant within-hemisphere correlations between left but not right hemisphere regions. These included left perisylvian regions classically associated with language functions (left inferior frontal, left superior temporal and left transverse temporal cortical regions) as well as other regions. Significant correlations between left regions and a right superior temporal region were also found. In general, these findings show a pattern of cross-hemisphere symmetry at rest and of hemisphere asymmetry during stimulation. Moreover, the asymmetry observed during stimulation appears to be superimposed upon a pattern of cross-hemisphere symmetry similar to that observed in the unstimulated state. 相似文献
992.
Charles Flicker Steven H. Ferris Thomas Crook Raymond T. Bartus 《Brain and language》1987,31(2):187-200
Young normals, elderly normals, and patients with either mild-to-moderate or severe senile dementia of the Alzheimer type (SDAT) were administered several tests of language function and remote memory. On all of the language tests examined, elderly normals exhibited a mild, nonsignificant performance decrement relative to the young normals. Advanced SDAT patients were markedly impaired on all of the tests. Early dementia patients were most impaired, relative to aged normals, on tests of object naming, category instance fluency, and remote memory. The deficit was smaller on the WAIS vocabulary subtest, on selecting the name of a visually presented object, and on recalling the function of an object. Early SDAT patients were least impaired in selecting the picture of an object after its name had been provided and in selecting objects that belong to a specified functional category. The results are consistent with the notion that the language dysfunction in early SDAT is due to a deficit in semantic memory function in which general, categorical information remains available whereas information about specific attributes becomes less accessible. The object naming test might be useful in the assessment of treatment effects upon SDAT because of its sensitivity and specificity to dementia, its high face validity, and its independence of recent memory. 相似文献
993.
When sighted persons try to identify one of two speech utterances coming from different directions, they display both a frontal position advantage, i.e., better recognition of inputs from the front than of those from the rear, and a right-side advantage, better recognition of inputs from the right than of those from the left. The present study demonstrates a dissociation of the two effects in blind subjects (N = 10) who showed no frontal position advantage together with a right-side advantage superior to that of control sighted subjects (N = 16). There was no systematic difference between congenitally blind subjects and noncongenitals. The absence of frontal position advantage in the blind is consistent with the notion that this effect originates in the habit of sighted listeners to orient toward the source of heard speech. The occurrence of at least normal right-side advantage in the blind does not support recent suggestions of reduced lateralization of language functions in such subjects. 相似文献
994.
Two left-handed siblings with developmental stuttering are comprehensively described. The methods of study included speech and language evaluation, neurological and neuropsychological examinations, dichotic listening, auditory evoked responses, electroencephalogram, and CT scan asymmetry measurements. The data from each sibling showed evidence of anomalous cerebral dominance on many of the variables investigated. The CT scan measurements showed atypical asymmetries, especially in the occipital regions. These findings support the theory that stuttering may be related to anomalous cerebral dominance, both on functional as well as structural bases. Implications of anomalous dominance and the resultant effect of hemispheric rivalry on speech fluency are discussed. 相似文献
995.
Leonard A. Jason Charles L. Gruder Steven Martino Brian R. Flay Richard Warnecke Nathaniel Thomas 《American journal of community psychology》1987,15(1):57-72
At the work site, smoking accounts for increased health care expenses and worker absenteeism due to smoking-related illness and reduced productivity and lost wages. Developing comprehensive and accessible smoking cessation programs at the work site is an important objective for health care professionals. In this study, employees of 43 corporations participated in a televised smoking cessation program accompanied by self-help manuals. The media component involved presenting a smoking cessation program on a network television affiliate station during the 4:30 p.m. and 10:00 p.m. news for 20 days. Employees at half the corporations also had access to semiweekly self-help group meetings. Adding self-help support groups to a program involving self-help manuals and the media reports was found to significantly increase abstinence and its maintenance over time. The implications of using the media, self-help groups, and work site locations in large-scale community-based interventions are discussed. 相似文献
996.
Roger P. Weissberg Emory L. Cowen Bohdan S. Lotyczewski Mary F. Boike N. Ahvay Orara Peter Stalonas Sharon Sterling Ellis L. Gesten 《American journal of community psychology》1987,15(4):387-401
Teacher-rated adjustment differences among young elementary school children from (a) a recent sample and a 1974 cohort, and (b) urban/suburban, male/female, and grade-level subgroups were examined. A problem behavior checklist (Classroom Adjustment Rating Scale) and a school competence measure (Health Resources Inventory) for 974 children from 5 urban and 5 suburban schools were completed by 101 first- to fourth-grade teachers. Children from the more current cohort were rated as significantly more maladjusted than those from the earlier sample on 8 of 10 adjustment variables. In the recent sample, girls and suburban children evidenced a greater number of school competencies and fewer problem behaviors than boys and urban children, respectively. The implications of these findings for the future use of the teacher rating scales are discussed. 相似文献
997.
998.
999.
Judgments on the subjective duration of simple and complex imagined situations are studied. Four facets, concerning the evaluation of the situation (pleasant/unpleasant) and the characteristics of its events (many/few, variable/monotonous, difficult/easy), are taken into account. These facets proved significant for duration judgments in previous studies in which subjects were exposed to situations varying with respect to one of them. In this paper, we study whether these time-perception facets have comparable effects on the symbolic temporal basis of duration judgments. that is, whether they allow one to account for differences in the beliefs about duration experience in imagined situations. Two approaches were chosen: (1) Three groups of subjects compared the durations of all possible pairs of situations characterized by facet elments x and y. The confusion probabilities could be scaled in one dimension for all groups. The facet elements defined intervals that were hierarchically nested. (2)The facets allowed us to distinguish 24 structuples. For each of them, a concrete situation was described in writing. Seventy-six subjects rated the subjective durations of the situations. The structuples led to a partial order that corresponded well to the duration ratings. Moreover, three of the facets showed significant main effects, and the fourth interacted significantly with two others. Finally, the facets were useful in explaining the similarity structure of the duration ratings. 相似文献
1000.
Experiment 1 of the current research failed to replicate Toppino and Di George’s (1984) finding that older children but not preschoolers showed a spacing effect. Instead, we obtained the spacing effect in all the age groups tested (preschool, kindergarten, first-grade, and third-grade children). The effect was demonstrated with two types of material, words and pictures. Experiment 2 focused on the role that very brief spacings, with no intervening items between repetitions, play in later retention. Age groups and materials were the same as in Experiment 1. Four different levels of spacing were included (0-, 1.1-,2.5-, and 5-sec intervals). The spacing effect was again obtained for all age groups with both words and pictures. The results of both experiments suggest that the spacing effect does not emerge with development. 相似文献