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51.
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人工知能(AI)和大脑理论领域中提出的许多问题其实由来以久,本章的目的是简短地展现其部分历史渊源.第一部分题为1943年以前的道路,追述发生在1943年前的事;就在这一年发表了三篇非同凡响的论文:McCulloch 和 Pitts 提出神经网络的一种逻辑理论;Rosenbleuth、Wiener 和 Bigelow 断言,带反馈的机器富于目的性;而 Craik 把大脑模拟外界的能力视为智能产生之关键.第二部分题为控制论的确立和解体,表明控制论怎样从上述这些研究中脱颍而出,却仅孕育了许多分立的新兴学科——如人工智能、生物控制论、认知心理学以及神经模拟——它们各行其是;同时还表明大脑理论怎样崛起于此.第三部分随后描述 AI 与大脑理论的新联盟,它为解决四、五十年代控制论诸问题提供了新思路.我们首先概述在认知科学的旗帜下人工智能、认知心理学以及语言学的薪联盟.尔后探看人工智能与认知心理学研究者们对并行论的日益关注如何导致所谓“联结主义”或 PDP(并行分布处理)模式的发展.这种模式藉助大脑理论滋益了该联盟. 相似文献
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To investigate the nature of the frames of reference used to control an arm movement aimed at a visual target, we studied the accuracy of movements differing by the initial arm and eye positions. The results support the assumption that in darkness target location is internally represented in an egocentric frame of reference. Furthermore, when movements carried out with and without eye saccade are compared, it appears that foveating the target changes the reference used to generate the reaching arm movements, that is, the oculocentric reference is replaced by a head-trunk reference. An explanation for this phenomenon could be that a steady body-related landmark is needed to insure stable registering of the target location in the surrounding space, despite displacement of the body segments with respect to one another. 相似文献
55.
Experiments were designed to examine the influence of criterion and feedback information in the learning of a two-dimensional drawing task. Experiment 1 showed that when the task criterion is well known to the subject, the combined presentation of criterion information and information feedback facilitates the rate of acquisition of the skill but not its overall performance level of achievement. Experiment 2 showed that when the task criterion information is not well known to the subject, presentation of criterion information facilitates both the rate of acquisition and the overall performance level and, furthermore, is essential if configuration information feedback is to be utilized effectively. Experiment 3 showed that it is the combined presentation of criterion and configuration information feedback rather than the isolate presentation of either type of information alone, that facilitates learning and performance. Collectively, the findings from the three experiments suggest an interactive effect of prior knowledge by the learner and type of augmented information in facilitating the acquisition of skill, according to the constraints imposed in the task. The data are consistent with the proposal that the degrees of freedom in the information available to support motor skill learning must match the degrees of freedom to be constraint in the perceptual-motor workspace. 相似文献
56.
Languages differ in their phonological structure and physcholinguists have begun to explore the conseqence, of this fact for speech perception. We review research documenting that listeners attune their perceptual processes finaly to exploit the phonological regularities of their nativ language. As a consequence, these perceptual process are fill-adapted to listening to languages that do not display such, regularities. Thus, not only do late language-learners have trouble speaking a second language, also they do not hear it as native speakers do; worse, they apply their native language listening prosedures which may actually interfere with successful processing of the non-native input. We also present data from studies on infants showing that the initial attuning occurs early in life; very yong infants are sensitive to the relevant phonological regularities which distinguish different languages, and quickly distinguish the native language of their environment from languages with different regularities. 相似文献
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中国和澳大利亚父母报告的儿童社会性发展 总被引:4,自引:1,他引:3
采用作者编制的《3-9岁儿童社会性发展量表》的英译本,在284名澳大利亚儿童中进行测试。结果表明,对于社会文化背景差异巨大的中国和澳大利亚,本量表具有较好的稳定性和跨文化适用性。儿童社会性发展的各个方面,在中澳父母心目中占有不同地位:中国父母重视自我意识、社会技能、意志品质,而澳大利亚父母更重视社会技能和社会情绪的发展。在中澳两个样本中,女孩的社会性发展量表得分均高于男孩。 相似文献
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Changes in interlimb coupling, and their role in the development of bimanual coordination, were studied longitudinally in 6- to 12-month-old infants (N = 6). Infants were observed while they were reaching for simple objects of 2 different sizes. Their use of a uni-versus bimanual strategy for reaching as well as the coupling of their bimanual movements were compared; progress in bimanual coordination of complementary movements was evaluated on 8 different bimanual tasks. The bimanual tasks involved an asymmetrical cooperation between the 2 hands. Although spatiotemporal coupling of bimanual reaching movements did not decrease during the age period studied, infants around 7 months of age used their 2 hands infrequently for reaching. Occurrences of bimanual reaching were particularly low at the session preceding the first bimanual success at a bimanual task. This suggests that the temporal coincidence between greater independence of the 2 hands and progress in bimanual coordination of complementary movements acts in 2 directions: Infants may be more at ease when using their 2 hands in differentiated patterns as the hands move less in synchrony, but, in turn, they may be less likely to move their hands in synchrony as the anticipate mirror manipulations of the object less. The frequency of bimanual reaches increased toward the end of the 1st year. This might have been caused by an increase in the repertoire of bimanual asymmetrical object manipulations and by the fact that the development of bimanual coordination allows infants to manipulate objects with complementary movements even after a bimanual approach toward the object. 相似文献
60.
Crosbie J Williams A Lattal K Anderson M 《Journal of the experimental analysis of behavior》1997,68(2):161-175
The principal aim of the present experiments was to assess whether punishment increased or decreased the rate of unpunished behavior (contrast and induction, respectively) for which reinforcement rate was held constant, with physical and nonphysical punishers (electric shock and response cost), pigeon and human subjects, signaled and unsignaled components (multiple and mixed schedules), and the presence or absence of a blackout period between components. Across the three experiments there were 20 punishment conditions. Induction was found in nine of those, less consistent response-rate reduction was found in three, contrast was found in four, and in four there was no change in responding from conditions without punishment. Contrast occurred consistently only with multiple schedules during the first exposure to electric-shock punishment. Induction and no change, however, were found with every combination of the independent variables studied. Four conclusions regarding the interactions between punished and unpunished responding emerged from the present results: (a) Both contrast and induction occurred with the reinforcement rate held constant and a blackout between components, (b) induction was more common than contrast, (c) contrast occurred only in the presence of a stimulus different from that correlated with the punisher, and (d) contrast diminished with prolonged exposure to punishment. None of the current theoretical accounts of punishment contrast can explain the present results. 相似文献