Differences in Noun and Verb Processing in Lexical Decision Cannot be Attributed to Word Form and Morphological Complexity Alone

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.     

义符在中文名词和动词分类中的作用

通过3个实验,考察了义符在中文名词和动词分类中的作用。实验1表明,义符提供了重要的语法种类信息,在中文名词和动词分类中有重要作用。当义符与词类一致时分类快,与词类相反时对分类起干扰作用。实验2表明,高频词分类时间短,错误率亦低。义符和词频有显著的交互作用,义符对低频词分类作用更大。实验3表明,具体性高的词分类时间短,错误率亦低。义符和具体性之间无显著的交互作用。整个研究表明,义符不仅是结构的“块”,也是语义的“块”,还是语法的“块”。所以如此,与中文名词和动词的结构特点有关。中文名词大多用义符标记事物的物质组成,动词大多用义符标记动作发出的器官或完成动作的工具。义符的语法意义的发现丰富了中文和中文认知的理论,对中文教学也有重要启示     

Neural correlates of comprehension and production of nouns and verbs in Chinese

This paper reports a conjunction analysis between semantic relatedness judgment and semantic associate generation of Chinese nouns and verbs with concrete or abstract meanings. The results revealed a verb-specific task-independent region in LpSTG&MTG, and task-dependent activation in a left frontal region in semantic judgment and the left SMG in semantic associate production. The observation of word class effects converged on Yu, Law, Han, Zhu, and Bi (2011), but contrasted with null findings in previous reports using a lexical decision task. While word class effects in the left posterior temporal cortices have been described in previous studies of languages with rich inflectional morphology, the significance of this study lies in its demonstration of the effects in these regions in a language known to have little inflectional morphology. In other words, differential neural responses to nouns and verbs can be observed without confounding from morphosyntactic operations or contrasts between actions and objects.     

汉语名词、动词和动名兼类词语义加工的偏侧化现象——来自ERP的研究

将ERP技术和半视野技术相结合,采用词汇判断任务,对汉语名词、动词和动名兼类词在左脑和右脑中的加工机制进行了考察。实验结果显示,名词和动词的N400仅在左视野/右脑存在差异,名词和动词的N400在左视野/右脑和右视野/左脑中都比偏（动）和偏（名）更负。不同词类的LPC在右视野/左脑中没有显著差异;偏（名）和偏（动）的LPC在左视野/右脑中比名词和动词更正。实验结果表明,在没有语境条件下,汉语名词和动词的差异主要在具体性上,动名兼类词体现出不同于名词、动词的加工机制。     

动词论元结构复杂性加工的认知神经机制

动词论元结构复杂性表现在论元数量、论元范畴选择模式、题元角色指派模式和映射方式四个方面。大部分实证研究表明, 更多的论元数量、选择性论元范畴、选择性题元角色指派以及非典型映射, 使动词论元结构加工的认知神经机制更复杂。多论元加工功能脑区主要涉及左侧额下回和外侧裂周后部; 选择性论元范畴加工功能脑区主要涉及左侧额下回、额叶中后部、颞上回和颞叶中后部; 选择性题元角色指派加工功能脑区主要涉及外侧裂周后部、左侧额叶中后部和额下回; 非典型映射加工功能脑区主要涉及左侧额下回、颞上回、颞中回和颞叶后部。左侧额下回可能涉及初始句法加工、动词次范畴确定、句法移位和非宾格动词语义加工, 左侧额叶中后部可能涉及初始句法加工和动词次范畴确定, 左侧颞上回和颞叶中后部可能涉及表层句法加工和表层论元句法-语义整合, 外侧裂周后部可能涉及论元语义表征。动词论元结构加工过程和动词词汇特征表明, 复杂性某些方面存在交互作用。动词论元结构复杂性与加工难易的对应关系、复杂性加工难度层级和交互作用的认知神经机制以及汉语动词论元结构复杂性加工认知神经机制等议题, 有待进一步探讨。     

Shindigs,brunches, and rodeos: The neural basis of event words

Events (e.g., “running” or “eating”) constitute a basic type within human cognition and human language. We asked whether thinking about events, as compared to other conceptual categories, depends on partially independent neural circuits. Indirect evidence for this hypothesis comes from previous studies showing elevated posterior temporal responses to verbs, which typically label events. Neural responses to verbs could, however, be driven either by their grammatical or by their semantic properties. In the present experiment, we separated the effects of grammatical class (verb vs. noun) and semantic category (event vs. object) by measuring neural responses to event nouns (e.g., “the hurricane”). Participants rated the semantic relatedness of event nouns, as well as of two categories of object nouns—animals (e.g., “the alligator”) and plants (e.g., “the acorn”)—and three categories of verbs—manner of motion (e.g., “to roll”), emission (e.g., “to sparkle”), and perception (e.g., “to gaze”). As has previously been observed, we found larger responses to verbs than to object nouns in the left posterior middle (LMTG) and superior (LSTG) temporal gyri. Crucially, we also found that the LMTG responds more to event than to object nouns. These data suggest that part of the posterior lateral temporal response to verbs is driven by their semantic properties. By contrast, a more superior region, at the junction of the temporal and parietal cortices, responded more to verbs than to all nouns, irrespective of their semantic category. We concluded that the neural mechanisms engaged when thinking about event and object categories are partially dissociable.     

To watch, to see, and to differ: an event-related potential study of concreteness effects as a function of word class and lexical ambiguity

Electrophysiological techniques were used to assess the generalizability of concreteness effects on word processing across word class (nouns and verbs) and different types of lexical ambiguity (syntactic only and combined syntactic/semantic). The results replicated prior work in showing an enhanced N400 response and a sustained frontal negativity to concrete as compared with abstract nouns. The effect of concreteness on the N400 generalized to all word class and ambiguity conditions, whereas the frontal effect was present for all word types except for the syntactically and semantically ambiguous items when these were used as verbs. The seemingly dissociable ERP effects of concreteness at frontal and central/posterior electrode sites revealed by these data suggest that concreteness may impact multiple aspects of neurocognitive processing.     

Neuroanatomically separable effects of imageability and grammatical class during single-word comprehension

The present study characterizes the neural correlates of noun and verb imageability and addresses the question of whether components of the neural network supporting word recognition can be separately modified by variations in grammatical class and imageability. We examined the effect of imageability on BOLD signal during single-word comprehension of nouns and verbs. Subjects made semantic similarity judgments while undergoing functional magnetic resonance imaging (fMRI). Nouns and verbs were matched on imageability, and imageability varied continuously within a grammatical category. We observed three anatomically separable effects: a main effect of grammatical class, a main effect of imageability, and an imageability by grammatical class cross-over interaction. The left superior parietal lobule and a region in the left fusiform responded similarly to increases in noun and verb imageability; the left superior temporal gyrus showed greater activity for verbs than nouns after imageability was matched across grammatical class; and, in both the left middle temporal gyrus and the left inferior frontal lobe, a decrease in noun but not verb imageability resulted in higher BOLD signal. The presence of reliable and anatomically separable main effects of both imageability and grammatical class renders unlikely the hypothesis that previously reported dissociations between nouns and verbs can be dismissed as imageability effects. However, some regions previously thought to respond to grammatical class or imageability instead respond to the interaction of these variables.     

The time course of lemma retrieval in lexical decision tasks.

The time course of lemma retrieval was assessed in lexical decision tasks with semantic and syntactic priming using monomorphemic English nouns, verbs, and ambiguous word forms. The results showed distinct processing patterns associated with different syntactic categories. The findings suggest that among other factors lemma retrieval is affected by different types of constraints working on entity/event construal. The findings can be used to propose a view according to which a lemma represents an activation state triggered by a number of processing factors, such as conventionalized conceptual architecture of a lexical item and its relative activation threshold.     

Predicting language: MEG evidence for lexical preactivation

It is widely assumed that prediction plays a substantial role in language processing. However, despite numerous studies demonstrating that contextual information facilitates both syntactic and lexical–semantic processing, there exists no direct evidence pertaining to the neural correlates of the prediction process itself. Using magnetoencephalography (MEG), this study found that brain activity was modulated by whether or not a specific noun could be predicted, given a picture prime. Specifically, before the noun was presented, predictive contexts triggered enhanced activation in left mid-temporal cortex (implicated in lexical access), ventro-medial prefrontal cortex (previously associated with top-down processing), and visual cortex (hypothesized to index the preactivation of predicted form features), successively. This finding suggests that predictive language processing recruits a top-down network where predicted words are activated at different levels of representation, from more ‘abstract’ lexical–semantic representations in temporal cortex, all the way down to visual word form features. The same brain regions that exhibited enhanced activation for predictive contexts before the onset of the noun showed effects of congruence during the target word. To our knowledge, this study is one of the first to directly investigate the anticipatory stage of predictive language processing.     

语法语境下汉语名动分离的ERP研究

运用ERP技术,从语法角度,通过词语搭配判断任务,考察汉语名词和动词加工的脑神经机制。实验结果显示,在适合的语法语境中,名词、动词和动名兼类词所诱发出ERP差异主要反应在P200、N400和P600三个ERP成分上。在正确的语境中,名词诱发出更大的P200,而动词则诱发出比名词更大的N400和减小的P600;当动名兼类词分别用作名词和动词时,虽然二者的N400没有显著差异,但前者诱发出一个增大的P600。根据实验结果认为：汉语名词和动词具有不同的神经表征和加工机制,名词和动词的语法功能在汉语名动分离中起了重要的作用     

Effect of Representational Distance Between Meanings on Recognition of Ambiguous Spoken Words

Previous research indicates that mental representations of word meanings are distributed along both semantic and syntactic dimensions such that nouns and verbs are relatively distinct from one another. Two experiments examined the effect of representational distance between meanings on recognition of ambiguous spoken words by comparing recognition of unambiguous words, noun–verb homonyms, and noun–noun homonyms. In Experiment 1, auditory lexical decision was fastest for unambiguous words, slower for noun–verb homonyms, and slowest for noun–noun homonyms. In Experiment 2, response times for matching spoken words to pictures followed the same pattern and eye fixation time courses revealed converging, gradual time course differences between conditions. These results indicate greater competition between meanings of ambiguous words when the meanings are from the same grammatical class (noun–noun homonyms) than when they are from different grammatical classes (noun–verb homonyms).     

Dissociation and association of the embodied representation of tool-use verbs and hand verbs: An fMRI study

Embodied semantic theories suppose that representation of word meaning and actual sensory-motor processing are implemented in overlapping systems. According to this view, association and dissociation of different word meaning should correspond to dissociation and association of the described sensory-motor processing. Previous studies demonstrate that although tool-use actions and hand actions have overlapping neural substrates, tool-use actions show greater activations in frontal–parietal–temporal regions that are responsible for motor control and tool knowledge processing. In the present study, we examined the association and the dissociation of the semantic representation of tool-use verbs and hand action verbs. Chinese verbs describing tool-use or hand actions without tools were included, and a passive reading task was employed. All verb conditions showed common activations in areas of left middle frontal gyrus, left inferior frontal gyrus (BA 44/45) and left inferior parietal lobule relative to rest, and all conditions showed significant effects in premotor areas within the mask of hand motion effects. Contrasts between tool-use verbs and hand verbs demonstrated that tool verbs elicited stronger activity in left superior parietal lobule, left middle frontal gyrus and left posterior middle temporal gyrus. Additionally, psychophysiological interaction analyses demonstrated that tool verbs indicated greater connectivity among these regions. These results suggest that the brain regions involved in tool-use action processing also play more important roles in tool-use verb processing and that similar systems may be responsible for word meaning representation and actual sensory-motor processing.     

Studying the grammatical aspects of word recognition: lexical priming,parsing, and syntactic ambiguity resolution

Two experiments are reported examining the relationship between lexical and syntactic processing during language comprehension, combining techniques common to the on-line study of syntactic ambiguity resolution with priming techniques common to the study of lexical processing. By manipulating grammatical properties of lexical primes, we explore how lexically based knowledge is activated and guides combinatory sentence processing. Particularly, we find that nouns (like verbs, see Trueswell & Kim, 1998) can activate detailed lexically specific syntactic information and that these representations guide the resolution of relevant syntactic ambiguities pertaining to verb argument structure. These findings suggest that certain principles of knowledge representation common to theories of lexical knowledge—such as overlapping and distributed representations—also characterize grammatical knowledge. Additionally, observations from an auditory comprehension study suggest similar conclusions about the lexical nature of parsing in spoken language comprehension. They also suggest that thematic role and syntactic preferences are activated during word recognition and that both influence combinatory processing.     

The syntactic priming effect: Evoked response evidence for a prelexical locus

Twenty subjects made lexical decisions in a syntactic priming paradigm. Target stimuli (nouns, verbs, abiguous noun--verb words, and nonsense words) were immediately preceded on each trial by a function word syntactic prime, creating appropriate or inappropriate syntactic contexts for the real word targets. Evoked responses to the targets were recorded from left and right frontal, temporal, and temporoparietal sites. Principal components analysis revealed a component peaking at 140 msec which discriminated words in appropriate contexts from words in inappropriate contexts, independent of lexical syntactic class, with maximal discrimination at temporoparietal sites. Evidence for the identification of the syntactic class of target items was not observed in the evoked response until 80 msec after this syntactic priming effect occurred. These results suggest a prelexical locus for the syntactic priming effect. The implications of these results for current conceptions of the modularity of the mental lexicon are discussed.     

Does Global Context Modulate Cerebral Asymmetries? A Review and New Evidence on Word Imageability Effects

In this article we examine whether the distribution of function across the right and left cerebral hemispheres for lexical processing is influenced by the global context within which words are presented. A review of previously published studies indicates that the ubiquitous right visual field (RVF)/left hemisphere advantage for word recognition may be reduced or eliminated for nouns, content words, or high image words, but only when such items are presented along with verbs, function words, or low image words. However, paradoxically, when the former items are presented in more homogeneous contexts, the RVF advantage is uniformly observed. We propose that the processing efficiency of a hemisphere for a given stimulus depends on that item's relation to the other stimuli provided, that is, the global context. This was examined in a visual half-field experiment that varied whether high and low image nouns were presented in homogeneous (blocked lists) or heterogeneous (mixed lists) contexts. An unvarying RVF advantage was observed for high image words in homogeneous contexts, but this advantage was eliminated when the same items were presented in heterogeneous contexts. We suggest that stimulus heterogeneity maximizes reliance on differing, but complementary, computational biases across hemispheres. Hence, the extent to which the left and right hemispheres are recruited for the recognition of individual word types can vary dynamically with variation in the stimulus environment.     

The role of grammatical class on word recognition

The double dissociation between noun and verb processing, well documented in the neuropsychological literature, has not been supported in imaging studies. Recent imaging studies, in fact, suggest that once confounding with semantics is eliminated, grammatical class effects only emerge as a consequence of building frames. Here we assess this hypothesis behaviorally in two visual word recognition experiments. In Experiment 1, participants made lexical decisions on verb targets. We manipulated the grammatical class of the prime words (either nouns or verbs and always introduced in a minimal phrasal context, i.e., “the + N” or “to + V”), and their semantic similarity to a target (related vs. unrelated). We found reliable effects of grammatical class, and no interaction with semantic similarity. Experiment 2 further explored this grammatical class effect, using verb targets preceded by semantically unrelated verb vs. noun primes. In one condition, prime words were presented as bare words; in the other, they were presented in the minimal phrasal context used in Experiment 1. Grammatical class effects only arose in the latter but not in the former condition thus providing evidence that word recognition does not recruit grammatical class information unless it is provided to the system.     

Processing distinctions between stems and affixes: evidence from a non-fluent aphasic patient

In this paper, we study the ability of a non-fluent aphasic patient, BN, to comprehend morphologically complex words when they appear in utterance contexts. We first establish that he is insensitive to the contextual appropriateness of both derived and inflected words. In a further experiment we show that he has no difficulty processing the stems of complex words and conclude that his problem is with the bound morphemes themselves. We then ask whether this problem is due to his inability to access either the phonological form of a morphologically complex word or its semantic and/or syntactic content. We find that only the access of semantic and syntactic content is impaired. We conclude from these six studies that: (a) BN presents a counter-example to the claim that non-fluent patients have particular difficulty with those aspects of morphology which have a syntactic function; (b) BN processes both derived and inflected words by mapping the sensory input onto the entire full-form of a complex word, but the semantic and syntactic content of the stem alone is accessed and integrated into the context. The semantic and syntactic implications of the suffix are never evaluated. This implies separate representation of the stems and suffixes of some types of morphologically complex words.     

习得年龄对客体和动作图画口语命名的不同影响：ERP研究

词汇习得年龄指人们最早理解单词意义时的年龄, 已有研究发现早习得词汇的阅读反应时间短于晚习得词汇, 研究者对于词汇习得年龄效应的认知机制存在争论。本研究运用事件相关电位技术, 考察了词汇习得年龄(早与晚)对客体图画和动作图画命名的影响。研究中采用图画命名任务, 要求被试在看到图画后迅速且准确地说出图画名称。结果发现早习得名词的命名快于晚习得名词, 而早习得动词的命名却慢于晚习得动词; 习得年龄对于名词产生的影响发生在图画呈现后的250~300 ms之间, 表现为早习得名词波幅小于晚习得名词, 而习得年龄对于动词产生的影响发生在图画呈现后的200~600 ms之间, 表现为早习得动词波幅大于晚习得动词。这表明名词产生中的习得年龄效应发生在词汇选择阶段, 支持了语义假设的观点; 动词产生过程中的习得年龄效应出现在多个加工阶段, 包括了词汇选择、音韵编码和语音编码阶段, 这与动词语义的多重性及其与动作相关的脑区激活有关, 支持了网络可塑性假说的观点。     

Connectivity among semantic associates: an fMRI study of semantic priming

Semantic priming refers to a reduction in the reaction time to identify or make a judgment about a stimulus that has been immediately preceded by a semantically related word or picture and is thought to result from a partial overlap in the semantic associates of the two words. A semantic priming lexical decision task using spoken words was presented in event-related fMRI and behavioral paradigms. Word pairs varied in terms of semantic relatedness and the connectivity between associates. Thirteen right-handed subjects underwent fMRI imaging and 10 additional subjects were tested in a behavioral version of the semantic priming task. It was hypothesized priming would be greatest, reaction time fastest, and cortical activation reduced the most for related word pairs of high connectivity, followed by related word pairs of low connectivity, and then by unrelated word pairs. Behavioral and fMRI results confirmed these predictions. fMRI activity located primarily in bilateral posterior superior and middle temporal regions showed modulation by connectivity and relatedness. The results suggest that these regions are involved in semantic processing.