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41.
This article reports the results of 629 subjects in three experiments designed to replicate and extend the phenomenon of vicarious verbal conditioning. Experiment I replicated the finding that subjects who responded most to vicarious verbal conditioning were aware of the contingency involved. Experiment II attempted to examine the effects of prior history with the verbal reinforcer on vicarious verbal conditioning by providing seven groups of subjects with varying classic conditioning histories prior to vicarious verbal conditioning. The null results associated with this experiment were hypothesized to be due to the fact that the vicarious verbal conditioning took place in a language laboratory where the subjects could hear but not see the model. Experiment III replicated Experiment II in a live group context as was done in Experiment I. The results showed a) that vicarious verbal conditioning was again found to take place, b) that associating the verbal reinforcer with a tone or tone plus money via forward classic conditioning potentiated the effects of the verbal reinforcer, c) that backward classic conditioning did not potentiate the reinforcer, d) nor did either of two sensitization procedures potentiate the effects of the verbal reinforcer. Both aware and unaware subjects evidenced vicarious verbal conditioning.  相似文献   
42.
This research was designed to compare time judgments obtained under prospective conditions (in which subjects are instructed to attend to time) and retrospective conditions (in which subjects are unaware that they will be required to judge time). In Experiment 1, subjects prospectively or retrospectively judged the duration of intervals spent performing a perceptual-motor task at different levels of difficulty. The results showed that subjects tested under both research paradigms tended to give increasingly shorter and/or more inaccurate time judgments with increases in nontemporal task demands. Experiment 2 was designed to test the effects of attentional deployment on perceived time by comparing prospective and retrospective judgments under control, selective attention, and divided attention conditions. Both types of time judgments became increasingly inaccurate as attention was more broadly deployed. The results of these experiments are consistent with an attentional allocation model, and they suggest that nontemporal task demands disrupt or interfere with timing in both prospective and retrospective situations.  相似文献   
43.
The present study was designed to investigate whether a specific subgroup of learning-disabled children (attention-deficit-disordered, ADD) differed from their normal counterparts on Piagetian tasks of conservation. The subjects were 34 third-and fourth-grade children. Seventeen children had been diagnosed as ADD; the remaining half were designated as normal. The two groups were equivalent in chronological age, mental age, and intelligence. The results indicated significant differences between the two groups on tasks tapping conservation of substance and number. These results may support the theory of a lag in the development of conservation in children with specific learning disabilities (ADD). Implications of the present research for therapeutic and remedial programs that serve ADD children are also discussed.  相似文献   
44.
Male rats isolated for 60 days in adulthood spent less time investigating odors of females and urine-marked less over these odors than did males kept in groups of three. Isolated males did not differ from grouped males in their responses to odors of unfamiliar males or their own odors. After social experience the isolated males showed an increase in urine-marking but no change in odor preferences. Individual housing therefore appears to alter olfactory communication in the same way that it does other social behaviors and these changes may be mediated by the same mechanisms.  相似文献   
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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   
49.
In this study, verbal memory and naming abilities were investigated in reading disabled (RD) and control children who were characterized according to the presence or absence of attention deficit disorder (ADD). Results indicate that deficits in learning and memory for recently acquired information occur as a function of ADD rather than RD while deficits in naming are specific to RD rather than ADD. We conclude that ADD is a major source of additional and separate cognitive morbidity in RD children.  相似文献   
50.
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   
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