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341.
Using a preferential looking methodology with novel verbs, Gertner, Fisher and Eisengart (2006) found that 21-month-old English children seemed to understand the syntactic marking of transitive word order in an abstract, verb-general way. In the current study we tested whether young German children of this same age have this same understanding. Following Gertner et al. (2006), one group of German children was tested only after they had received a training/practice phase containing transitive sentences with familiar verbs and the exact same nouns as those used at test. A second group was tested after a training/practice phase consisting only of familiar verbs, without the nouns used at test. Only the group of children with the training on full transitive sentences was successful in the test. These findings suggest that for children this young to succeed in this test of syntactic understanding, they must first have some kind of relevant linguistic experience immediately prior to testing--which raises the question of the nature of children's linguistic representations at this early point in development.  相似文献   
342.
Research suggests equivocal findings on associations of catecholamines and mood. Our study investigated the associations of emotional state, blood pressure and catecholamines in 55 healthy males undergoing mental stress. We especially checked the reported link between norepinephrine (NE) and emotional irritation. Blood pressure (SBP, DBP) and heart rate (HR) were continuously monitored. NE and epinephrine (EPI) were measured before, after, and 20 minutes after stress. Participants were divided into irritated versus non-irritated and anxious versus non-anxious subjects by median split on their baseline questionnaires. The task elicited significant cardiovascular, hormonal, and psychological stress responses. NE levels were significantly correlated with irritation before stress. Irritated subjects showed significantly higher DBP and NE than non-irritated subjects. The higher NE and DBP levels in the irritated participants suggest detrimental psycho-physiological interrelations promoting the development of stress-mediated cardiovascular diseases. Heightened emotional irritation before stress may be regarded as a psychological risk factor.  相似文献   
343.
Money and possessions hold strong attractions, but being driven to acquire them in order to enhance one's social standing is associated with lowered well-being. Literatures on money and happiness, materialism, and cultural mediators are reviewed. Consumer well-being is associated with being neither very tight nor very loose with money, with having relatively low financial aspirations, and with being low in materialism. Price-related behaviors – whether to spend low, spend high, or attempt to maximize value – are ways of responding to economic outlay vis-à-vis material wants, and these "strategies" offer a window into broader consumer lifestyles: the Value Seeker type is tight with money and materialistic; the Big Spender is loose with money and materialistic; the Non-Spender is tight with money and not materialistic; and the Experiencer is loose with money and not materialistic. Each of these types is described in terms of the potentials for well-being as well as the risks. Intrinsic motivation emerges as a key to well-being. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
344.
A common denominator for the induction of morphological and functional plasticity in cultured hippocampal neurons involves the activation of excitatory synapses. We now demonstrate massive morphological plasticity in mature cultured hippocampal neurons caused by a brief exposure to glutamate. This plasticity involves a slow, 70%-80% increase in spine cross-section area associated with a significant reduction in the width of dendrites. These changes are age dependent and expressed only in cells >18 d in vitro (DIV). Activation of both NMDARs and AMPARs as well as a sustained rise of internal calcium levels are necessary for induction of this plasticity. On the other hand, blockade of network activity or mGluRs does not abolish the observed morphological plasticity. Electrophysiologically, a brief exposure to glutamate induces an increase in the magnitude of EPSCs evoked between pairs of neurons, as well as in mEPSC frequency and amplitude, in mature but not young cultures. These results demonstrate an age-dependent, rapid and robust morphological and functional change in cultured central neurons that may contribute to their ability to express long term synaptic plasticity.  相似文献   
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346.
The polyamines, spermine, spermidine, and putrescine, are a group of aliphatic amines that may act as physiological modulators of N-methyl-D-aspartate (NMDA) receptors. Although the modulatory role of polyamines in NMDA receptor function has long been known, the effects of polyamines on learning and memory only recently began to be unraveled. In the present study, we investigated the effect of bilateral infusions of spermidine (0.02-2 nmol), a polyamine agonist, into the CA1 region of the rat dorsal hippocampus on inhibitory avoidance learning 30 min pre-training, immediately post-training, 6 h post-training, or 10 min pre-test. Bilateral microinjections of 0.2 nmol spermidine prolonged step-down latencies compared to the respective control group when administered 30 min pre-training or immediately post-training. These results provide evidence that the modulatory effects of spermidine on the acquisition and/or early consolidation of memory of inhibitory avoidance tasks in the hippocampus occur within a limited time window.  相似文献   
347.
348.
Mathematical solutions to textbook word problems are correlated with semantic relations between the objects described in the problem texts. In particular, division problems usually involve functionally related objects (e.g., tulips-vases) and rarely involve categorically related objects (e.g., tulips-daisies). We examined whether middle school, high school, and college students use object relations when they solve division word problems (WP) or perform the less familiar task of representing verbal statements with algebraic equations (EQ). Both tasks involved multiplicative comparison statements with either categorically or functionally related objects (e.g., "four times as many cupcakes [commuters] as brownies [automobiles]"). Object relations affected the frequency of correct solutions in the WP task but not in the EQ task. In the latter task, object relations did affect the structure of nonalgebraic equation errors. We argue that students use object relations as "semantic cues" when they engage in the sense-making activity of mathematical modeling.  相似文献   
349.
Although researchers have studied employee lateness empirically (e.g., S. Adler & J. Golan, 1981; C. W. Clegg, 1983), few have attempted to describe the punctual employee. In the present study, results of a discriminant analysis on employees in Israel indicated that a personality characteristic, time urgency, a subcomponent of Type A behavioral pattern, distinguished between punctual and late employees. Organizational commitment and age of employee's youngest child also distinguished between the groups.  相似文献   
350.
The effect of sentence context on the processing of different aspects of meaning of unambiguous nouns by the two cerebral hemispheres was examined. Participants performed a lexical decision task on target words following two primes, an unambiguous noun preceded by an incomplete sentence. Priming sentences were consistent with either the dominant or the subordinate aspect of meaning of their final unambiguous word. Short and long SOAs were used. A principal finding of this study was that, when compared to unrelated aspects of meaning, for both the short and the long SOAs, the dominant and subordinate aspects of meaning of the unambiguous words were activated regardless of context in both hemispheres. However, the activation of the subordinate aspect of meaning of unambiguous words appears to be more sensitive to sentential context, especially when the unambiguous word is being processed by the left hemisphere.  相似文献   
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