首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   10195篇
  免费   236篇
  国内免费   29篇
  2012年   1059篇
  2011年   1245篇
  2010年   285篇
  2009年   119篇
  2008年   967篇
  2007年   973篇
  2006年   834篇
  2005年   718篇
  2004年   621篇
  2003年   633篇
  2002年   528篇
  2001年   351篇
  2000年   533篇
  1999年   219篇
  1998年   40篇
  1997年   76篇
  1996年   47篇
  1995年   34篇
  1994年   17篇
  1993年   46篇
  1992年   24篇
  1991年   28篇
  1990年   23篇
  1989年   28篇
  1988年   29篇
  1987年   27篇
  1986年   14篇
  1985年   20篇
  1984年   31篇
  1983年   34篇
  1982年   19篇
  1981年   21篇
  1979年   17篇
  1978年   20篇
  1977年   14篇
  1976年   19篇
  1975年   16篇
  1974年   16篇
  1959年   30篇
  1958年   95篇
  1957年   67篇
  1956年   68篇
  1955年   58篇
  1954年   52篇
  1953年   59篇
  1952年   36篇
  1951年   41篇
  1950年   38篇
  1949年   27篇
  1948年   17篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Deacon SH  Benere J  Castles A 《Cognition》2012,122(1):110-117
There is increasing evidence of a relationship between orthographic processing skill, or the ability to form, store and access word representations, and reading ability. Empirical research to date has not, however, clarified the direction of this relationship. We examined this question in a three-year longitudinal study of children from Grades 1 to 3. We included standard measures of orthographic processing skill, at both the lexical and sublexical level, and word reading accuracy, as well as controls of vocabulary, non-verbal reasoning, and phonological awareness. In all analyses, word reading predicted progress in acquiring orthographic processing skill, regardless of grade level or orthographic processing measure. In contrast, orthographic processing skill did not predict progress in word reading. Our results suggest that, between Grades 1 and 3, children acquire orthographic processing skill through their reading and that this ability, as characterized by the most common tasks used to date, does not play an independent role in supporting reading acquisition.  相似文献   
992.
Cvejic E  Kim J  Davis C 《Cognition》2012,122(3):442-453
Prosody can be expressed not only by modification to the timing, stress and intonation of auditory speech but also by modifying visual speech. Studies have shown that the production of visual cues to prosody is highly variable (both within and across speakers), however behavioural studies have shown that perceivers can effectively use such visual cues. The latter result suggests that people are sensitive to the type of prosody expressed despite cue variability. The current study investigated the extent to which perceivers can match visual cues to prosody from different speakers and from different face regions. Participants were presented two pairs of sentences (consisting of the same segmental content) and were required to decide which pair had the same prosody. Experiment 1 tested visual and auditory cues from the same speaker and Experiment 2 from different speakers. Experiment 3 used visual cues from the upper and the lower face of the same talker and Experiment 4 from different speakers. The results showed that perceivers could accurately match prosody even when signals were produced by different speakers. Furthermore, perceivers were able to match the prosodic cues both within and across modalities regardless of the face area presented. This ability to match prosody from very different visual cues suggests that perceivers cope with variation in the production of visual prosody by flexibly mapping specific tokens to abstract prosodic types.  相似文献   
993.
Cognitive deficits and particularly deficits in working memory (WM) capacity are common features in neuropsychiatric disorders. Understanding the underlying mechanisms through which WM capacity can be improved is therefore of great importance. Several lines of research indicate that dopamine plays an important role not only in WM function but also for improving WM capacity. For example, pharmacological interventions acting on the dopaminergic system, such as methylphenidate, improve WM performance. In addition, behavioral interventions for improving WM performance in the form of intensive computerized training have recently been associated with changes in dopamine receptor density. These two different means of improving WM performance--pharmacological and behavioral--are thus associated with similar biological mechanisms in the brain involving dopaminergic systems. This article reviews some of the evidence for the role of dopamine in WM functioning, in particular concerning the link to WM development and cognitive plasticity. Novel data are presented showing that variation in the dopamine transporter gene (DAT1) influences improvements in WM and fluid intelligence in preschool-age children following cognitive training. Our results emphasize the importance of the role of dopamine in determining cognitive plasticity.  相似文献   
994.
People must often engage in sequential sampling in order to make predictions about the relative quantities of two options. We investigated how directional motives influence sampling selections and resulting predictions in such cases. We used a paradigm in which participants had limited time to sample items and make predictions about which side of the screen contained more of a critical item. Sampling selections were biased by monetary desirability manipulations, and participants exhibited a desirability bias for both dichotomous and continuous predictions.  相似文献   
995.
J Gervain  R Guevara Erra 《Cognition》2012,125(2):263-287
Does statistical learning (Saffran, Aslin, &; Newport, 1996) offer a universal segmentation strategy for young language learners? Previous studies on large corpora of English and structurally similar languages have shown that statistical segmentation can be an effective strategy. However, many of the world’s languages have richer morphological systems, with sometimes several affixes attached to a stem (e.g. Hungarian: iskoláinkban: iskolá-i-nk-ban school.pl.poss1pl.inessive ‘in our schools’). In these languages, word boundaries and morpheme boundaries do not coincide. Does the internal structure of words affect segmentation? What word forms does segmentation yield in morphologically rich languages: complex word forms or separate stems and affixes? The present paper answers these questions by exploring different segmentation algorithms in infant-directed speech corpora from two typologically and structurally different languages, Hungarian and Italian. The results suggest that the morphological and syntactic type of a language has an impact on statistical segmentation, with different strategies working best in different languages. Specifically, the direction of segmentation seems to be sensitive to the affixation order of a language. Thus, backward probabilities are more effective in Hungarian, a heavily suffixing language, whereas forward probabilities are more informative in Italian, which has fewer suffixes and a large number of phrase-initial function words. The consequences of these findings for potential segmentation and word learning strategies are discussed.  相似文献   
996.
Early language development is characterized by predictable changes in the words children produce and the complexity of their utterances. In infants, these changes could reflect increasing linguistic expertise or cognitive maturation and development. To disentangle these factors, we compared the acquisition of English in internationally-adopted preschoolers and internationally-adopted infants. Parental reports and speech samples were collected for 1 year. Both groups showed the qualitative shifts that characterize first-language acquisition. Initially, they produced single-word utterances consisting mostly of nouns and social words. The appearance of verbs, adjectives and multiword utterances was predicted by vocabulary size in both groups. Preschoolers did learn some words at an earlier stage than infants, specifically words referring to the past or future and adjectives describing behavior and internal states. These findings suggest that cognitive development plays little role in the shift from referential terms to predicates but may constrain children's ability to learn some abstract words.  相似文献   
997.
Items that are clustered according to shared content may violate the principle of conditional independence commonly used in item response theory. This paper investigates the capabilities of a logistic item response model in relation to locally dependent item responses. The model includes main effect and interaction parameters that are computed as linear functions of the latent trait. The paper explains the interpretation of the parameters, the maximum likelihood estimation algorithm, the information matrix and some results concerning parameter identifiability. The problem of over-fitting the data is addressed in a simulation study, and two real data examples are described to illustrate the approach, one from the context of a sample survey and the other from ability testing using testlets.  相似文献   
998.
Time, an everyday yet fundamentally abstract domain, is conceptualized in terms of space throughout the world's cultures. Linguists and psychologists have presented evidence of a widespread pattern in which deictic time-past, present, and future-is construed along the front/back axis, a construal that is linear and ego-based. To investigate the universality of this pattern, we studied the construal of deictic time among the Yupno, an indigenous group from the mountains of Papua New Guinea, whose language makes extensive use of allocentric topographic (uphill/downhill) terms for describing spatial relations. We measured the pointing direction of Yupno speakers' gestures-produced naturally and without prompting-as they explained common expressions related to the past, present, and future. Results show that the Yupno spontaneously construe deictic time spatially in terms of allocentric topography: the past is construed as downhill, the present as co-located with the speaker, and the future as uphill. Moreover, the Yupno construal is not linear, but exhibits a particular geometry that appears to reflect the local terrain. The findings shed light on how, our universal human embodiment notwithstanding, linguistic, cultural, and environmental pressures come to shape abstract concepts.  相似文献   
999.
Shtulman A  Valcarcel J 《Cognition》2012,124(2):209-215
When students learn scientific theories that conflict with their earlier, naïve theories, what happens to the earlier theories? Are they overwritten or merely suppressed? We investigated this question by devising and implementing a novel speeded-reasoning task. Adults with many years of science education verified two types of statements as quickly as possible: statements whose truth value was the same across both naïve and scientific theories of a particular phenomenon (e.g., “The moon revolves around the Earth”) and statements involving the same conceptual relations but whose truth value differed across those theories (e.g., “The Earth revolves around the sun”). Participants verified the latter significantly more slowly and less accurately than the former across 10 domains of knowledge (astronomy, evolution, fractions, genetics, germs, matter, mechanics, physiology, thermodynamics, and waves), suggesting that naïve theories survive the acquisition of a mutually incompatible scientific theory, coexisting with that theory for many years to follow.  相似文献   
1000.
Yu J  Hung DL  Tseng P  Tzeng OJ  Muggleton NG  Juan CH 《Cognition》2012,124(2):251-255
Witnessing emotional events such as arousal or pain may impair ongoing cognitive processes such as inhibitory control. We found that this may be true only half of the time. Erotic images and painful video clips were shown to men and women shortly before a stop signal task, which measures cognitive inhibitory control. These stimuli impaired inhibitory control only in men and not in women, suggesting that emotional stimuli may be processed with different weights depending on gender.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号