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   591篇
  免费   43篇
  2023年   6篇
  2021年   11篇
  2020年   18篇
  2019年   20篇
  2018年   27篇
  2017年   24篇
  2016年   24篇
  2015年   16篇
  2014年   15篇
  2013年   68篇
  2012年   20篇
  2011年   30篇
  2010年   23篇
  2009年   9篇
  2008年   17篇
  2007年   24篇
  2006年   18篇
  2005年   16篇
  2004年   14篇
  2003年   20篇
  2002年   9篇
  2000年   12篇
  1999年   12篇
  1998年   7篇
  1997年   10篇
  1996年   7篇
  1995年   4篇
  1994年   5篇
  1992年   7篇
  1991年   6篇
  1990年   8篇
  1989年   6篇
  1988年   4篇
  1987年   4篇
  1986年   10篇
  1985年   7篇
  1984年   7篇
  1983年   11篇
  1982年   7篇
  1981年   6篇
  1978年   4篇
  1977年   5篇
  1976年   6篇
  1975年   6篇
  1974年   3篇
  1973年   7篇
  1970年   3篇
  1968年   3篇
  1967年   3篇
  1966年   3篇
排序方式: 共有634条查询结果,搜索用时 15 毫秒
81.
In learning a successive go/no-go discrimination between a positive display consisting of the elements A and B, and negative display consisting of A-alone, pigeons first trained to peck A shift to pecking the distinguishing B element. In order to learn whether or not the shift to B is facilitated by B's function as a signal of the reinforcer, apart from the direct reinforcement of B responses, six arrangements of the elements with respect to the food reinforcer were used. Discrete trials were terminated by a single peck or after 4 sec. The A and B elements were dots of different color. The most critical comparison was between two groups, both of which received no reinforcement for a response directed to B. In one case, B signaled the reinforcer: An A response was reinforced when B was present but not when A appeared alone. In the other, B signaled the absence of a reinforcer: An A response was nonreinforced when B was present, while the response to A-alone was reinforced. During training and in extinction many more reponses were made to B when it signaled the reinforcer than when it signaled its absence. It is concluded that in a discrimination between AB positive and A negative the shift from pecking A to pecking B is facilitated by B's role as a signal for the reinforcer even on trials in which the peck is not made to B. Results from certain other groups showed that, unless pecks shifted to B within the positive display, pecks to A continued on the negative, A-alone trials as well as on the positive AB trials.  相似文献   
82.
The development and use of first line screening instruments is an essential first step in assessing behavior disorders in very young children. The Early Childhood Behavior Screen (ECBS) is a parent-report measure for behavior disorders and is normed on young children (1–5 years old) living in poverty. The current study presents psychometric support for the discriminative validity of the ECBS’s 10-item Challenging Behavior Scale (CBS) as a first-line screener for externalizing behavior problems for preschool aged-children in poverty. The study’s sample included 673 participants (M age years = 2.81; 63.2 % male; 65.8 % African American) that all met the federal definitional standard for living in poverty. A confirmatory factor analysis was run to provide support for the ECBS factor structure. Receiver operating characteristics (ROC) curve analyses were used to test the CBS’s ability to distinguish between 428 clinic-referred children and 245 non-clinic-referred children. Results showed an acceptable fit model for the ECBS, providing further evidence of its construct validity. Optimal cut-scores by child age derived from the ROC curve analyses were provided with corresponding levels of sensitivity, specificity, and positive and negative predictive values. Sensitivity rates for cut scores ranged from 0.76 to 0.83 and specificity rates ranged from 0.88 to 0.95. Acceptable test–retest reliability and good internal consistency also was observed. The CBS quickly identifies young children from low-income, urban, diverse populations that may be at-risk for developing significant behavior disorders and should be considered by health care professionals who work with very young children.  相似文献   
83.
The study of development is, in and of itself, the study of change over time, but emotions, particularly emotional reactivity and emotional regulation, also unfold over time, albeit over briefer time‐scales. Adolescence is a period of development characterized by marked changes in emotional processes and rewiring of the underlying neural circuitry, making this time of life formative. Yet this period is also a time of increased risk for anxiety and mood disorders. Changes in the temporal dynamics of emotional processes (e.g. magnitude, time‐to‐peak and duration) occur during this developmental period and have been associated with risk for mood and anxiety disorders. In this article, we describe how the temporal dynamics of emotions change during adolescence and how they may increase risk for these psychopathologies. We highlight studies that illustrate how formalizing temporal neurodynamics of emotion may enhance links among levels of analyses from neurobiological to real‐world, moment‐to‐moment experiences.  相似文献   
84.
A growing literature in psychology shows that human voice pitch—perceived “highness” or “lowness” as determined by the physiology of the throat—influences how speakers are perceived. This leads to the prediction that candidate voice pitch influences voters. Here this question is addressed with two studies. The first is an experiment conducted with a large national sample of U.S. adults. The results show that men and women prefer to vote for male and female candidates with lower pitched voices. The second study examines the outcomes of the 2012 U.S. House elections. When facing male opponents, candidates with lower voices won a larger vote share. However, when facing female opponents, candidates with higher voices were more successful and particularly so in the case of male candidates. In synthesizing research on the human voice and voter behavior and triangulating evidence from a controlled experiment and a large observational study of actual elections, this article illustrates that candidate voice pitch influences election outcomes.  相似文献   
85.
Despite documented effects on fetal brain development, little is currently known about the relationship between maternal pregnancy hypertension and child neuropsychological outcomes. This brief report examined the association between maternal hypertension during pregnancy and children’s social cognition and executive functioning when children were 18 months, 3 years, and 4.5 years. A community sample of 501 families (23 hypertensive mothers; 478 nonhypertensive) was recruited when children were newborns. Social cognition (including theory of mind [ToM]) and executive functioning (EF) were measured using a battery of age-appropriate standardized and/or observational tasks. Information on pregnancy and prenatal factors were measured via maternal report when children were newborns. After controlling for prenatal and demographic covariates, the presence of hypertension difficulties during pregnancy was associated with all measures of social cognition, ToM, and EF. A secondary analysis comparing the hypertension group (n = 23) to a nonhypertensive matched control group (n = 23) supported the effect of pregnancy hypertension on children’s social-cognitive and EF development. Future studies using obstetrical records are encouraged based on these preliminary findings.  相似文献   
86.
Results of a recent study of spatial working memory are presented in support of the claim by Jenkins and her colleagues (Jenkins, Myerson, Hale, &; Fry, 1999) that secondary tasks produce larger interference effects in individuals with higher simple spans than in individuals with lower simple spans. Because spans and interference effects were assessed independently, this study refutes the claim by Oberauer and Süß (2000) that the relation between span and interference effect size is merely an artifact of regression to the mean. In contrast with the present findings, Oberauer and Süß did not find evidence of larger interference effects in higher span individuals, but the reason for this may be straightforward: The secondary tasks that they used did not produce significant interference. Recent findings by Logie and his colleagues indicate that phonological similarity and word length effects are larger in individuals with higher word spans (Logie, Della Sala, Laiacona, Chalmers, &; Wynn, 1996). These results, those of Jenkins, Myerson, et al. (1999), and the results reported here suggest that, across individuals, the absolute effect size for many manipulations that decrease memory span is an increasing function of simple span.  相似文献   
87.
88.
Everyone agrees that infants possess general mechanisms for learning about the world, but the existence and operation of more specialized mechanisms is controversial. One mechanism—rule learning—has been proposed as potentially specific to speech, based on findings that 7‐month‐olds can learn abstract repetition rules from spoken syllables (e.g. ABB patterns: wo‐fe‐fe, ga‐tu‐tu…) but not from closely matched stimuli, such as tones. Subsequent work has shown that learning of abstract patterns is not simply specific to speech. However, we still lack a parsimonious explanation to tie together the diverse, messy, and occasionally contradictory findings in that literature. We took two routes to creating a new profile of rule learning: meta‐analysis of 20 prior reports on infants’ learning of abstract repetition rules (including 1,318 infants in 63 experiments total), and an experiment on learning of such rules from a natural, non‐speech communicative signal. These complementary approaches revealed that infants were most likely to learn abstract patterns from meaningful stimuli. We argue that the ability to detect and generalize simple patterns supports learning across domains in infancy but chiefly when the signal is meaningfully relevant to infants’ experience with sounds, objects, language, and people.  相似文献   
89.
In bilingual language environments, infants and toddlers listen to two separate languages during the same key years that monolingual children listen to just one and bilinguals rarely learn each of their two languages at the same rate. Learning to understand language requires them to cope with challenges not found in monolingual input, notably the use of two languages within the same utterance (e.g., Do you like the perro? or ¿Te gusta el doggy?). For bilinguals of all ages, switching between two languages can reduce the efficiency in real‐time language processing. But language switching is a dynamic phenomenon in bilingual environments, presenting the young learner with many junctures where comprehension can be derailed or even supported. In this study, we tested 20 Spanish–English bilingual toddlers (18‐ to 30‐months) who varied substantially in language dominance. Toddlers’ eye movements were monitored as they looked at familiar objects and listened to single‐language and mixed‐language sentences in both of their languages. We found asymmetrical switch costs when toddlers were tested in their dominant versus non‐dominant language, and critically, they benefited from hearing nouns produced in their dominant language, independent of switching. While bilingualism does present unique challenges, our results suggest a united picture of early monolingual and bilingual learning. Just like monolinguals, experience shapes bilingual toddlers’ word knowledge, and with more robust representations, toddlers are better able to recognize words in diverse sentences.  相似文献   
90.
Emotion perception deficits could be due to disrupted connectivity of key nodes in the salience and emotion network (SEN), including the amygdala, subgenual anterior cingulate cortex (sgACC), and insula. We examined SEN resting-state (rs-)fMRI connectivity in rMDD in relation to Facial Emotion Perception Test (FEPT) performance. Fifty-two medication-free people ages 18 to 23 years participated. Twenty-seven had major depressive disorder (MDD) in remission (rMDD, 10 males), as MDD is associated with emotion perception deficits and alterations in rsfMRI. Twenty-five healthy controls (10 males) also participated. Participants completed the FEPT during fMRI, in addition to an 8-minute eyes-open resting-state scan. Seed regions of interest were defined in the amygdala, anterior insula and sgACC. Multiple regression analyses co-varied diagnostic group, sex and movement parameters. Emotion perception accuracy was positively associated with connectivity between amygdala seeds and regions primarily in the SEN and cognitive control network (CCN), and also the default mode network (DMN). Accuracy was also positively associated with connectivity between the sgACC seeds and other SEN regions, and the DMN, particularly for the right sgACC. Connectivity negatively associated with emotion perception was mostly with regions outside of these three networks, other than the left insula and part of the DMN. This study is the first to our knowledge to demonstrate relationships between facial emotion processing and resting-state connectivity with SEN nodes and between SEN nodes and regions located within other neural networks.  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