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1.
Impaired verb fluency: a sign of mild cognitive impairment   总被引:3,自引:0,他引:3  
We assessed verb fluency vs. noun and letter-based fluency in 199 subjects referred for cognitive complaints including Subjective Cognitive Impairment, Mild Cognitive Impairment, and Alzheimer's disease. ANCOVAs and factor analyses identified verb, noun, and letter-based fluency as distinct tasks. Verb fluency performance in Mild Cognitive Impairment differed significantly from Subjective Cognitive Impairment and Alzheimer's disease. Reduced verb fluency thus appears to be a linguistic marker for incipient dementia. One possibility is that the verb fluency deficit in Mild Cognitive Impairment results from degenerative processes known to occur in the parahippocampal region.  相似文献   

2.
We studied noun and verb naming in three main variants of frontotemporal dementia: the frontal variant(Fv-FTD), primary progressive aphasia (PPA) and semantic dementia (SD). We further distinguished PPA in nonfluent and fluent forms and restricted diagnosis of SD to subjects with progressive semantic breakdown leading to agnosia for words and objects. Fv-FTD and nonfluent-PPA named objects better than actions, SD showed an inverse dissociation and no specific pattern emerged in fluent-PPA. In this last group, in spite of the broad definition of fluent aphasia, quite heterogeneous patterns of language disorders and word class dissociation emerged when single-subject analyses were performed. In fv-FTD correlations between executive tasks and action naming were stronger than between executive tasks and object naming. We conclude that both linguistic and non linguistic factors, in particular an executive deficit, contribute to grammatical class dissociation. We also suggest that the fluent vs. nonfluent distinction does not reflect the complexity of primary aphasia.  相似文献   

3.
A noun/verb dissociation with a relative verb deficit was found in patients affected by Parkinson's disease, even in relatively early stages, when mental deterioration is not severe. This finding is compatible with earlier observations, according to which verbs are dealt with in more anterior regions with respect to nouns. It also supports the speculation that the co-ordination and the manipulation of information associated with a verb world rely on the frontostriatal system.  相似文献   

4.
Any theory of language must account for how children learn verbs, the gateway to grammar. Yet verbs can be difficult to learn. Building on Gentner's 'natural partitions hypothesis' we suggest that, to learn a verb, infants must conceptualize components of events and map verbs in the ambient language onto those components. Although toddlers detect and categorize at least some of the conceptual underpinnings of verb categories, the mapping of verbs onto these representations is not transparent. Mapping is a difficult problem in its own right. The Emergentist Coalition Model that has been used to explain noun learning also begins to explain how children move from perceptual to social and then to linguistic information to link verbs to actions and events.  相似文献   

5.
An ongoing debate in political psychology is about whether small wording differences have outsized behavioral effects. A leading example is whether subtle linguistic cues embedded in voter mobilization messages dramatically increase turnout. An initial study analyzing two small‐scale field experiments argued that describing someone as a voter (noun) instead of one who votes (verb) increases turnout rates 11 to 14 points because the noun activates a person's social identity as a voter. A subsequent study analyzing a large‐scale field experiment challenged this claim and found no effect. But questions about the initial claim's domain of applicability persist. The subsequent study may not have reproduced the conditions necessary for the psychological phenomenon to occur, specifically the electoral contexts were not competitive or important enough for the social identity to matter. To address the first of these critiques, as well as other potential explanations for different results between the first two studies, we conduct a large‐scale replication field experiment. We find no evidence that this minor wording change increases turnout levels. This research provides new evidence that the strategy of invoking the self does not appear to consistently increase turnout and calls into question whether subtle linguistic cues have outsized behavioral effects.  相似文献   

6.
This study examines the processing of a specific linguistic distinction, the mass/count distinction, in patients suffering from Alzheimer’s disease (AD) and mild cognitive impairment (MCI). Fourteen AD and 10 MCI subjects were tested using a sentence grammaticality judgement task where grammaticality violations were caused by determiner–noun mismatches, as well as a sentence–picture matching task to assess their ability to access mass and count readings of dual nouns. Considerable heterogeneity was observed within each subject group, and performance across groups was almost identical. It is concluded that a combination of linguistic and attentional and/or learning factors are responsible for the range of impairments; specifically, a subset of subjects exhibit no linguistic nor attentional/learning impairment, another subset exhibit only an attentional and/or learning impairment but no linguistic impairment, and a third subset (comprising more than half of the subjects included in this study) exhibit a linguistic impairment. It is postulated that the latter group have difficulty processing sense extensions in metonymous nouns. It is further claimed that, at least within the limits of the study, language impairments can be of the same severity and nature across AD and MCI subjects.  相似文献   

7.
徐芃  熊健 《心理学报》2012,44(9):1160-1166
个体的语言表征是一种随机现象, 在连续句子构成的语言表征中, 句子主语表征现象具有马氏性。采用马尔科夫链模型建构句子主语表征的状态转移概率矩阵, 发现主语表征的名词(n)/代词(r)是一个正则链。主语表征变化规律反映思维指向的变化规律, 个体根据对环境的适应需要, 通过第一个句子的主语表征反映出客观思维或主观思维指向的随机性, 通过N个句子则反映出个体既关注外界又关注自我的思维指向稳定性的特征。外显的语言表征是观察内隐的心理变化的客观线索, 运用数学模型的方法, 通过语言表征的规律可以对心理活动的可能变化做出预报。  相似文献   

8.
本研究采用交叉聚合设计,从词汇量角度考察了两岁左右汉语婴儿是否存在“名词优势”现象。在前测中,110名18、24和30个月龄的儿童接受了PCDI量表和父母问卷调查;6个月后,18个月和24个月组接受了PCDI量表的再测。本研究将“名词优势效应”定义为“(名词得分–动词得分)/词汇总分”(以k值表示),将名词得分大于动词得分者定义为“名词优势者”。结果发现:(1)从各年龄组均值来看,18个月组名词优势效应较小(k = .07),24及30个月组名词优势效应显著增大(k = .11~.19)。(2)从个体水平来看,18个月组名词优势者和动词优势者约各占50%(p > .05),而24、30个月组中81~100%的儿童都是名词优势者。该结果提示,以往不同研究之间的分歧可能是由于名词优势是随年龄而动态变化的。  相似文献   

9.
Testing one's memory of previously studied information reduces the rate of forgetting, compared to restudy. However, little is known about how this direct testing effect applies to action phrases (e.g., “wash the car”) – a learning material relevant to everyday memory. As action phrases consist of two different components, a verb (e.g., “wash”) and a noun (e.g., “car”), testing can either be implemented as noun‐cued recall of verbs or verb‐cued recall of nouns, which may differently affect later memory performance. In the present study, we investigated the effect of testing for these two recall types, using verbally encoded action phrases as learning materials. Results showed that repeated study–test practice, compared to repeated study–restudy practice, decreased the forgetting rate across 1 week to a similar degree for both noun‐cued and verb‐cued recall types. However, noun‐cued recall of verbs initiated more new subsequent learning during the first restudy, compared to verb‐cued recall of nouns. The study provides evidence that testing has benefits on both subsequent restudy and long‐term retention of action‐relevant materials, but that these benefits are differently expressed with testing via noun‐cued versus verb‐cued recall.  相似文献   

10.
In Russian negative sentences the verb’s direct object may appear either in the accusative case, which is licensed by the verb (as is common cross-linguistically), or in the genitive case, which is licensed by the negation (Russian-specific “genitive-of-negation” phenomenon). Such sentences were used to investigate whether case marking is employed for anticipating syntactic structure, and whether lexical heads other than the verb can be predicted on the basis of a case-marked noun phrase. Experiment 1, a completion task, confirmed that genitive-of-negation is part of Russian speakers’ active grammatical repertoire. In Experiments 2 and 3, the genitive/accusative case manipulation on the preverbal object led to shorter reading times at the negation and verb in the genitive versus accusative condition. Furthermore, Experiment 3 manipulated linear order of the direct object and the negated verb in order to distinguish whether the abovementioned facilitatory effect was predictive or integrative in nature, and concluded that the parser actively predicts a verb and (otherwise optional) negation on the basis of a preceding genitive-marked object. Similarly to a head-final language, case-marking information on preverbal noun phrases (NPs) is used by the parser to enable incremental structure building in a free-word-order language such as Russian.  相似文献   

11.
The work reported here experimentally investigates a striking generalization about vocabulary acquisition: Noun learning is superior to verb learning in the earliest moments of child language development. The dominant explanation of this phenomenon in the literature invokes differing conceptual requirements for items in these lexical categories: Verbs are cognitively more complex than nouns and so their acquisition must await certain mental developments in the infant. In the present work, we investigate an alternative hypothesis; namely, that it is the information requirements of verb learning, not the conceptual requirements, that crucially determine the acquisition order. Efficient verb learning requires access to structural features of the exposure language and thus cannot take place until a scaffolding of noun knowledge enables the acquisition of clause-level syntax. More generally, we experimentally investigate the hypothesis that vocabulary acquisition takes place via an incremental constraint-satisfaction procedure that bootstraps itself into successively more sophisticated linguistic representations which, in turn, enable new kinds of vocabulary learning. If the experimental subjects were young children, it would be difficult to distinguish between this information-centered hypothesis and the conceptual change hypothesis. Therefore the experimental "learners" are adults. The items to be "acquired" in the experiments were the 24 most frequent nouns and 24 most frequent verbs from a sample of maternal speech to 18-24-month-old infants. The various experiments ask about the kinds of information that will support identification of these words as they occur in mother-to-child discourse. Both the proportion correctly identified and the type of word that is identifiable changes significantly as a function of information type. We discuss these results as consistent with the incremental construction of a highly lexicalized grammar by cognitively and pragmatically sophisticated human infants, but inconsistent with a procedure in which lexical acquisition is independent of and antecedent to syntax acquisition.  相似文献   

12.
How children go about learning the general regularities that govern language, as well as keeping track of the exceptions to them, remains one of the challenging open questions in the cognitive science of language. Computational modeling is an important methodology in research aimed at addressing this issue. We must determine appropriate learning mechanisms that can grasp generalizations from examples of specific usages, and that exhibit patterns of behavior over the course of learning similar to those in children. Early learning of verb argument structure is an area of language acquisition that provides an interesting testbed for such approaches due to the complexity of verb usages. A range of linguistic factors interact in determining the felicitous use of a verb in various constructions —associations between syntactic forms and properties of meaning that form the basis for a number of linguistic and psycholinguistic theories of language. This article presents a computational model for the representation, acquisition, and use of verbs and constructions. The Bayesian framework is founded on a novel view of constructions as a probabilistic association between syntactic and semantic features. The computational experiments reported here demonstrate the feasibility of learning general constructions, and their exceptions, from individual usages of verbs. The behavior of the model over the timecourse of acquisition mimics, in relevant aspects, the stages of learning exhibited by children. Therefore, this proposal sheds light on the possible mechanisms at work in forming linguistic generalizations and maintaining knowledge of exceptions.  相似文献   

13.
The study investigates the lexical representation of Italian noun/verb homographs, introducing a factor which has been analysed in production studies: the specific-word frequency (SWF). The SWF parameter allows to understand whether the grammatical class information is specified within the lexical knowledge or it is selected during post-lexical stages. We ran six lexical decision tasks employing the priming paradigm and a grammatical decision task to investigate the lexical representation of noun/verb homographs. In addition, we sought to determine the role played by the frequency of representations and the temporal activation of the grammatical class information. Our findings support the claim that these forms have independent representations for each syntactic role they can play. We interpreted these findings in the light of what we call the “Nominal Dominance” effect, which affects the lexical access of noun/verb homographs. We also discuss the relation between nominal dominance and lexical frequency.  相似文献   

14.
This article examines the evolution in understanding of frontotemporal dementia (FTD) during the last four decades. A central theme is the recognition of heterogeneity. Originally construed as a disorder of behaviour and executive impairment, FTD is now known also to be associated with alterations in language, conceptual knowledge and praxis. An absence of neurological signs is the hallmark of many FTD patients, but there is also an established association with motor neurone disease (MND), progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). FTD is commonly defined as an early onset dementia, yet about a quarter of patients present after the age of 65. The underlying pathological protein is tau, TDP-43 or more rarely fused-in-sarcoma (FUS). Distinct genetic mutations have been identified in familial FTD. There are predictable relationships between clinical phenotype, pathological substrate and genetic mutation. For example, a circumscribed semantic disorder predicts TDP-43 pathology, and speech or limb apraxia tau pathology. The co-occurrence of MND predicts TDP-43 pathology, and PSP and CBD tau pathology. FUS pathology is associated with very youthful onset, stereotyped behaviours and caudate atrophy. Non-fluent aphasia is linked to progranulin (GRN) mutations and MND and psychosis to repeat expansions in the C9orf72 gene. Despite striking worldwide consensus in findings there remain some issues of contention, largely related to the classification of FTD and its sub-variants. Understanding the diverse nature of FTD is crucial for effective diagnosis, management and the development of targeted therapies.  相似文献   

15.
Grammatical category ambiguity in aphasia   总被引:1,自引:0,他引:1  
This study asked whether aphasic adults show different noun/verb retrieval patterns based upon their clinical categorization as fluent or nonfluent. Participants selected either the noun or the verb meaning of target words, as presented in three contexts. The framework was that nouns (associated with temporal lobe function) are processed, stored, and retrieved separately from verbs (associated with frontal lobe function), implying separate status in the mental lexicon. Stimuli were homophonic homographs, words that are spelled and pronounced the same but which have different meanings (in this case, noun and verb meanings). Another contrast was the putative difference between systematic pairs (e.g., "kiss" and "farm"), in which noun and verb meanings are transparently related, and may be stored as a unit, and unsystematic pairs (e.g., "squash" and "sink"), in which noun and verb meanings are apparently unrelated, implying discrete storage. Results demonstrated significant interactions between fluent and nonfluent participants, suggesting that, as expected, fluent aphasic adults have more difficulty with nouns, nonfluent aphasic adults have more difficulty with verbs. There was no effect of systematicity. Contrary to expectations, verbs proved less vulnerable, rather than more vulnerable, to aphasic impairment.  相似文献   

16.
17.
It has been suggested that the effect of word category in noun and verb processing reflects typical word class properties, which can be characterized in terms of semantic as well as syntactic and morphological features. The present study is aimed at differentiating and discussing the relative contribution of these aspects with a main focus on syntactic and morphological processing. Experiment 1 established a processing advantage for nouns in German visual lexical decision, using nouns denoting biological and man-made objects as compared to transitive and intransitive verbs. Experiment 2 showed that the noun advantage persisted even when the morphological differences between word categories were reduced by using identical suffixes in nouns and verbs. Overall results suggest that the processing differences cannot be reduced to variables such as frequency, word form, or morphological complexity. Reaction time differences between transitive and intransitive verbs strengthen the role of syntactic information. In line with previous accounts the observed effects are discussed in terms of a category-specific combination of linguistic parameters.  相似文献   

18.
19.
Two experiments were performed to investigate the role of syntactic and pragmatic cues on the disambiguation of noun phrases of the form VERB+ing NOUN+s, like visiting relatives, that can be interpreted as either singular or plural noun phrases. Both experiments used a self-paced reading task in which reading times were measured for two words, a verb and an adverb, immediately following the potentially ambiguous noun phrase. The interpretation of the noun phrase as singular or plural was biased by pragmatic cues in the first experiment and by syntactic cues in the second experiment. In both experiments, subjects were faster to read the adverb following the verb when the interpretation biased by the cues agreed in number with the verb that immediately followed the target noun phrase than when it did not agree with the verb. These results suggest that pragmatic cues, like syntactic cues, can be utilized rapidly in sentence processing.  相似文献   

20.
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