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131.
Two predictions derived from Markovits and Barrouillet's (2001) developmental model of conditional reasoning were tested in a study in which 72 twelve-year-olds, 80 fifteen-year-olds, and 104 adults received a paper-and-pencil test of conditional reasoning with causal premises ("if cause P then effect Q"). First, we predicted that conditional premises would induce more correct uncertainty responses to the Affirmation of the consequent and Denial of the antecedent forms when the antecedent term is weakly associated to the consequent than when the two are strongly associated and that this effect would decrease with age. Second, uncertainty responding to the Denial of the antecedent form ("P is not true") should be easier when the formulation of the minor premise invites retrieval of alternate antecedents ("if something other than P is true"). The results were consistent with the hypotheses and indicate the importance of retrieval processes in understanding developmental patterns in conditional reasoning with familiar premises. 相似文献
132.
133.
The Serial Color-Word Test was administered to nonclinical volunteers of three age strata (17-29, 30-45, 46-65 yr.). Sex differences on the 17 variables of the test were explored for each age stratum. Only six significant intersex differences were found. In all age strata women scored significantly higher on linear regression of reading times in one of the last two subtests, i.e., R4 or R5. 相似文献
134.
Relationships between frequency of computer use or ability to use the computer effectively with the tendency to construct and process visual mental images were investigated by administering a computer-use questionnaire and a visualization questionnaire to a sample of 185 Italian and Spanish undergraduates. Analysis did not support associations between either (a) frequent computer use of any kind or (b) high competence in using the computer for various purposes and spontaneous use of imagery. 相似文献
135.
This study tested and refined a framework that proposes a mechanism for retrieving alternative causes and disabling conditions (Cummins, 1995) during reasoning. Experiment 1 examined the relation between different factors affecting retrieval. The test revealed high correlations between the number of possible alternative causes or disabling conditions and their strength of association and plausibility. Experiment 2 explored the hypothesis that due to a more extended search process, conditional inferences would last longer when many alternative causes or disabling conditions were available. Affirmation of the consequent (AC) and modus ponens (MP) latencies showed the hypothesized pattern. Denial of the antecedent (DA) and modus tollens (MT) inferences did not show latency effects. The experiment also identified an effect of the number of disabling conditions on AC and DA acceptance. Experiment 3 measured efficiency of disabler retrieval by a limited time, disabler generation task. As predicted, better disabler retrieval was related to lower acceptance of the MP and MT inferences. 相似文献
136.
Gutiérrez G. de Guzmán I. P. Martínez J. Ojeda-Aciego M. Valverde A. 《Studia Logica》2002,72(1):85-112
The tree-based data structure of -tree for propositional formulas is introduced in an improved and optimised form. The -trees allow a compact representation for negation normal forms as well as for a number of reduction strategies in order to consider only those occurrences of literals which are relevant for the satisfiability of the input formula. These reduction strategies are divided into two subsets (meaning- and satisfiability-preserving transformations) and can be used to decrease the size of a negation normal form A at (at most) quadratic cost. The reduction strategies are aimed at decreasing the number of required branchings and, therefore, these strategies allow to limit the size of the search space for the SAT problem. 相似文献
137.
Forty normal subjects (20 left-handed; 20 right-handed) were submitted to a proprioceptive straight ahead pointing task while blindfolded to study the effect of the hand used and of the hand preference on the estimation of the subjective sagittal middle. Results showed that left-handed and right-handed subjects both deviated to the left of the objective sagittal middle and presented an effect of the hand used and of the starting point affecting their straight ahead performance in a similar way. In all subjects whatever their manual preference, using the left hand and starting 30 degrees to left induced a tendency to deviate to the same side, whereas using the right hand and starting 30 degrees to right induced a tendency to place the subjective middle to the right of the objective middle. These results are interpreted with regard to the hypothesis of a cortical control of the position of the egocentric reference. 相似文献
138.
A generic problem in vision is to know which information drives the perception of a stimulus. We address this problem in a case study that involves the perceptual reversal of an ambiguous image (here, Dali's painting the Slave Market with the Disappearing Bust of Voltaire 1940). In experiment 1, we use 'bubbles' (Gosselin and Schyns, 2001 Vision Research 41 2261-2271) to disambiguate the image and to determine the specific visual information that drives each possible perception (here, the nuns versus the bust of Voltaire). Experiment 2 validates that this information does determine the selective perception of the ambiguous image. We adapted the spatial-frequency channels of observers selectively to the information that mediates one of the two perceptions, to induce the opposite perception of the ambiguous image in a transfer phase. Together, the results suggest a method of revealing the visual information that drives perception. 相似文献
139.
Lists of thematically related words were presented to participants with or without a concurrent task. In Experiments 1 and 2, respectively, English or Spanish word lists were either low or high in concreteness (concrete vs abstract words) and were presented, respectively, auditorily or visually for study. The addition of a concurrent visual or auditory task, respectively, substantially reduced correct recall and doubled the frequency of false memory reports (nonstudied critical or theme words). Divided attention was interpreted as having reduced the opportunity for participants to monitor successfully their elicitations of critical associates. Comparisons of concrete and abstract lists revealed significantly more recalls of false memories for abstract than concrete word lists. Comparisons between two levels of attention, two levels of word concreteness, and two presentation modalities failed to support the "more is less" effect by which enhanced correct recall is accompanied by increased frequencies of false memories. 相似文献
140.
Jezová D Skultétyová I Makatsori A Moncek F Duncko R 《Stress (Amsterdam, Netherlands)》2002,5(3):177-183
Neuroendocrine activation during stress is affected by many factors contributing to the variability of the stress response. The present study was aimed at evaluating long-term changes in hypothalamo-pituitary-adrenocortical (HPA) axis function and in hedonic behavior in adult offspring prenatally stressed by maternal food restriction, with attention on possible gender differences. Adult offspring were blood sampled via a tail artery cannula. Prenatally stressed females had significantly higher adrenal weights compared to males. Plasma ACTH levels, which rose in response to acute stress induced by handling, were significantly higher in females compared to those in males. A similar pattern was found in plasma corticosterone. The rise in ACTH levels was more pronounced in prenatally stressed rats though the rise in corticosterone failed to be modified. Corticotropin releasing hormone (CRH) and proopiomelanocortin mRNA levels in the hypothalamic paraventricular nucleus and anterior pituitary, respectively, were found to be unchanged. The present experiments failed to reveal a decrease in hedonic behavior in prenatally stressed rats. In contrast, in male offspring a tendency to a higher sucrose preference was observed. These data together with observed changes in hormone and CRH mRNA levels indicate that the gestational stress used did not result in a depression-like state in adult offspring. 相似文献