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891.
The aim of this study was to evaluate whether emergent conditional relations could be established with a go/no-go procedure using compound abstract stimuli. The procedure was conducted with 6 adult humans. During training, responses emitted in the presence of certain stimulus compounds (A1B1, A2B2, A3B3, B1C1, B2C2, and B3C3) were followed by reinforcing consequences (points); responses emitted in the presence of other compounds (A1B2, A1B3, A2B1, A2B3, A3B1, A3B2, B1C2, B1C3, B2C1, B2C3, B3C1 and B3C2) were not (i.e., extinction). During subsequent tests of emergent relations, new configurations (BA, CB, AC, and CA relations) were presented, formed by the recombination of training stimuli and structurally resembling tests usually employed in stimulus equivalence studies. Results showed that all 6 participants displayed immediate emergence of relations consistent with symmetry. Four participants exhibited emergent relations consistent with both transitivity and equivalence. These results indicate that a go/no-go procedure with compound stimuli can establish emergent conditional relations, thus providing a procedural alternative to the matching-to-sample procedures commonly used in studies of stimulus equivalence.  相似文献   
892.
Is it possible to learn to attend? The purpose of this article is to provide information about the development, administration, and contrast of an intervention program to improve selective and sustained attention in students from 5 to 19 years of age, all attending school, and with difficulties to learn the academic materials corresponding to their age. Two groups participated in the study: one with difficulties in selective attention and the other with difficulties in sustained attention. The group with selective attention difficulties was made up of 102 students, of whom 59 made up the experimental group and 43 the control group. The group of students with difficulties in sustained attention was made up of 106 students, of whom 58 participated as the experimental group and 48 as the control group. The results indicate that this kind of intervention (which combines visual therapy, cortical activation, and training with activity banks) is effective to improve attentional deficits, both at the level of selective attention and of sustained attention.  相似文献   
893.
The purpose of the present study is to analyse the relationship between sleep, burnout, and job strain in a sample of 316 healthy workers from various professional sectors. Multiple significant correlations between the principal sleep parameters, the dimensions of burnout, and job strain were found. The regression analyses show that sleep quality and various dimensions of job strain are significant predictors of several aspects of burnout. Sleep quality explains an even higher percentage of the variance in emotional exhaustion than the variance explained by more well-known variables such as job demands. Moreover, sleep quality interacts with aspects of job strain in its influence on the dimensions of burnout, although the exact relationship between these variables needs to be investigated in future longitudinal studies. Our results suggest that interventions to optimise sleep habits could prevent or alleviate burnout and could be a part of organisational work.  相似文献   
894.
The aim of the study was to explore the effect of visualizing food images under different mood states and food restriction conditions on the emotional modulation of two defense reflexes (startle reflex and cardiac defense). 72 women at risk of suffering from bulimia nervosa were assigned to two groups: 1) a group under induced positive, neutral, or negative mood state and, 2) a 6-hour-food-deprived group or a non-deprived group. Second-by-second heart rate and electromyogram activity from the orbiculari oculi region were recorded after the auditory stimulus. The results showed that, while viewing food images, non-deprived women under negative mood state potentiated the cardiac defense response and the startle motor reflex. Results are discussed in the context of emotional eating theories and Peter Lang's motivational priming model.  相似文献   
895.
The aim of this study was to investigate deficits in planning ability using an adapted version of the Modified Six Elements Test, from the Behavioral Assessment of the Dysexecutive Syndrome—BADS [Wilson, B. A., Alderman, N., Burgess, P. W., Emslie, H., & Evans, J. J. (1996). Behavioural Assessment of the Dysexecutive Syndrome (BADS). Bury St Edmunds, U.K.: Thames Valley Test Company. Trans. Ricardo O Souza, Sergio L Schmidt. Rio de Janeiro: Cognição]. Subjects were left- and right-frontal lobe lesion patients. Other measures of executive dysfunctions used were verbal fluency, the Wisconsin Card Sorting Test, and the Trail Making Test. These other instruments were sensitive to detect executive deficits in the left frontal lobe lesion group, except the Wisconsin Card Sorting Test, which showed impairment only for the frontal lobe lesion group as a whole. The Modified Six Elements Test detected planning disorders in left frontal lobe lesion patients. The deficit of these patients was due to a greater likelihood to break the rules of the task, that is, in plan-following processes, rather than in planning the strategic approach to solve it.  相似文献   
896.
Neural substrates for episodic encoding and recognition of unfamiliar faces   总被引:1,自引:0,他引:1  
Functional MRI was used to investigate brain activation in healthy volunteers during encoding of unfamiliar faces as well as during correct recognition of newly learned faces (CR) compared to correct identification of distractor faces (CF), missed alarms (not recognizing previously presented faces, MA), and false alarms (incorrectly recognizing newly presented faces, FA). Encoding was associated with frontal, occipital/fusiform, thalamic, and cerebellar activation. CR produced activation in frontal and cerebellar regions, whereas CF activated frontal and occipitotemporal regions as well as the thalamus. In contrast, MA was associated with frontal and thalamic activation, and FA with frontal activation. The CR minus CF comparison showed left lateral prefrontal and parietal activation, while no suprathreshold positive signal changes were detected when subtracting the other conditions (CR minus MA, CR minus FA, and vice versa). These results support the view that the successful episodic retrieval of newly learned faces is based on a dorsal visual stream mechanism.  相似文献   
897.
OBJECTIVE: To determine the relationship between joint variation in 2 dopaminergic genes and the likelihood of nonsmoking following treatment with bupropion sustained release (SR). DESIGN: Three hundred twenty-three participants in a bupropion SR smoking cessation effectiveness trial with 12-month follow-up were genotyped for variants of dopamine receptor gene DRD2 and dopamine transporter SLC6A3. MAIN OUTCOME MEASURES: Self-reported 7-day point prevalence of nonsmoking. RESULTS: Neither genotype alone was associated with 7-day point-prevalent nonsmoking at the 12-month follow-up. However, in the presence of the DRD2 A1 allele, SLC6A3 status was significantly associated with the likelihood of nonsmoking at the 12-month follow-up (individuals with DRD2 A1+ and SLC6A3 9- were more likely to be smoking). In the absence of the DRD2 A1 allele, the association between SLC6A3 status and nonsmoking was nonsignificant. CONCLUSION: Although these results are suggestive, a more compelling test is needed of the hypothesis that dopaminergic gene interaction underlies, in part, the likelihood of smoking following treatment with bupropion SR. Most likely this will come from larger studies involving prospective randomization to treatment based on genotype.  相似文献   
898.
Spatial visualization in physics problem solving   总被引:2,自引:0,他引:2  
Three studies were conducted to examine the relation of spatial visualization to solving kinematics problems that involved either predicting the two-dimensional motion of an object, translating from one frame of reference to another, or interpreting kinematics graphs. In Study 1, 60 physics-naíve students were administered kinematics problems and spatial visualization ability tests. In Study 2, 17 (8 high- and 9 low-spatial ability) additional students completed think-aloud protocols while they solved the kinematics problems. In Study 3, the eye movements of fifteen (9 high- and 6 low-spatial ability) students were recorded while the students solved kinematics problems. In contrast to high-spatial students, most low-spatial students did not combine two motion vectors, were unable to switch frames of reference, and tended to interpret graphs literally. The results of the study suggest an important relationship between spatial visualization ability and solving kinematics problems with multiple spatial parameters.  相似文献   
899.
Bloomfield''s “Linguistics as a Science” (1930/1970), Language (1933/1961), and “Language or Ideas?” (1936a/1970), and Skinner''s Verbal Behavior (1957) and Science and Human Behavior (1953) were analyzed in regard to their respective perspectives on science and scientific method, the verbal episode, meaning, and subject matter. Similarities between the two authors were found. In particular both asserted that (a) the study of language must be carried out through the methods of science; (b) the main function of language is to produce practical effects on the world through the mediation of a listener; and (c) a physicalist conception of meaning. Their differences concern the subject matter of their disciplines and their use of different models for the analysis of behavior. Bloomfield''s linguistics and Skinner''s functional analysis of verbal behavior are complementary approaches to language.  相似文献   
900.
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