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A square-wave grating from which the fundamental harmonic has been subtracted (missing fundamental grating) when viewed from a suitable distance appears similar to another grating of periodicity three times higher. The neurons of the visual cortex of the cat, in a given range of spatial frequencies characteristic of each cell, give similar responses to the two gratings. 相似文献
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Anthony Dickinson 《The Quarterly Journal of Experimental Psychology Section B: Comparative and Physiological Psychology》1996,49(1):60-80
The role of within-compound associations in the retrospective revaluation of causality judgements was investigated in a two-stage procedure in which the subjects were asked to learn whether or not different food stimuli caused an allergic reaction in hypothetical patients. In the compound-cue stage a number of compound cues, each consisting of a competing stimulus and a target stimulus, were associated with the reaction across a series of trials, whereas in the single-cue stage the subjects had the opportunity to learn which of the competing cues, when presented alone, caused the reaction. Each target stimulus was presented with the same competing cue across all compound trials in the consistent condition, but with a different competing cue on each trial in the varied condition. In a forward procedure, in which the single-cue stage preceded compound cue training, judgements of the causal effectiveness of the target stimuli were reduced or blocked by training them in compound with a competing cue that had been previously paired with the reaction. Moreover, the magnitude of this reduction was comparable in the consistent and varied conditions. This was not true, however, when the single- and compound-cue stages were reversed in the backward procedure. Judgements for target cues compounded with competing cues that were subsequently paired with the reaction were reduced only in the consistent condition. If it is assumed that stronger associations were formed between the competing and target stimuli during the compound-cue stage in the consistent condition than in the varied condition, this pattern suggests that the retrospective revaluation of causality judgements can be mediated by the formation of within-compound associations. 相似文献
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Gábor L. Ambrus 《Zygon》2020,55(4):875-897
We are easily misguided as to the true nature of Facebook, and tend to treat it simply as a powerful technological instrument in the service of human intentions. We can, however, gain a better picture of it through recourse to the Jewish tradition of the golem, an image of human beings, created by them in a re-enactment of their own creation by God. It turns into a magic servant in modernity with an inherent dynamic running between its human and its subhuman characteristics. This dynamic is the main cause behind its becoming uncontrollable. In like manner, what is subhuman in Facebook serves its masters and functions under their total control, but also empowers Facebook's increasingly human operation, an algorithm-based capability which raises growing doubts about what counts as human. Facebook implies the crisis of humanity which coincides with the “death of God,” that is, the obsolescence of the idea of a divine creator. 相似文献
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Previous research has revealed that individuals have expectations for the development of romance based on personal experience and cultural images. A series of research questions and hypotheses was generated and a sequence of hierarchical log-linear analysis models axis developed to test (a) the effect of gender and knowledge of relational stage and relationship type on prediction of next-occurring actions in the development of a romance, (b) the use of compliance-gaining strategies intended to advance a relationship to the next stage, and (c) justification of secondary goals in which participants reported why they chose the strategies they did as opposed to other alternatives. The data revealed effects for relational stage progression on prediction of ensuing actions. Ingratiation, explanation, and direct requests were popular strategies for developing intimacy. Gender differences in terms of secondary goals were reported. Results are discussed in terms of relational memory structures for the development of intimacy. 相似文献
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G. C. Preston A. Dickinson N. J. Mackintosh 《The Quarterly Journal of Experimental Psychology Section B: Comparative and Physiological Psychology》1986,38(2):217-237
Three experiments used a discriminated operant procedure to study conditional discrimination learning in rats. The first experiment showed that rats were capable of learning a biconditional discrimination in which two contexts served as conditional cues signalling the reinforcement contingencies associated with two discriminative stimuli. The discrimination was learned equally well when one discriminative stimulus signalled food, the other its absence, and when one stimulus signalled food, the other extinction plus mild footshock.
In Experiment 2 it was shown that prior training on such a conditional discrimination enhanced the subsequent context specificity of simple conditioning relative to control groups of animals for whom the prior training had not been conditional. Experiment 3 showed that a reversal of the significance of one pair of discriminative stimuli produced no spontaneous reversal in performance to a second, target, pair.
The pattern of results is best accounted for by an analysis of contextual conditional discrimination learning in terms of stimulus configurations and offers no support for the notion that rats may learn a general conditional rule or set. 相似文献
In Experiment 2 it was shown that prior training on such a conditional discrimination enhanced the subsequent context specificity of simple conditioning relative to control groups of animals for whom the prior training had not been conditional. Experiment 3 showed that a reversal of the significance of one pair of discriminative stimuli produced no spontaneous reversal in performance to a second, target, pair.
The pattern of results is best accounted for by an analysis of contextual conditional discrimination learning in terms of stimulus configurations and offers no support for the notion that rats may learn a general conditional rule or set. 相似文献
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