Phonological and conceptual activation in speech comprehension

We propose that speech comprehension involves the activation of token representations of the phonological forms of current lexical hypotheses, separately from the ongoing construction of a conceptual interpretation of the current utterance. In a series of cross-modal priming experiments, facilitation of lexical decision responses to visual target words (e.g., time) was found for targets that were semantic associates of auditory prime words (e.g., date) when the primes were isolated words, but not when the same primes appeared in sentence contexts. Identity priming (e.g., faster lexical decisions to visual date after spoken date than after an unrelated prime) appeared, however, both with isolated primes and with primes in prosodically neutral sentences. Associative priming in sentence contexts only emerged when sentence prosody involved contrastive accents, or when sentences were terminated immediately after the prime. Associative priming is therefore not an automatic consequence of speech processing. In no experiment was there associative priming from embedded words (e.g., sedate-time), but there was inhibitory identity priming (e.g., sedate-date) from embedded primes in sentence contexts. Speech comprehension therefore appears to involve separate distinct activation both of token phonological word representations and of conceptual word representations. Furthermore, both of these types of representation are distinct from the long-term memory representations of word form and meaning.     

双语即时切换下非目标语言语音和语义的激活状态

本研究采用双语即时切换范式, 探讨非熟练中英双语者在对目标语言(启动词)语音或语义的加工过程中非目标语言的激活状态。实验1设置了与启动词的翻译对等词存在语音相关或无关的两类配对词, 要求被试进行语音判断任务, 结果表明, 不论哪种切换条件, 两类配对词在反应时和P200成分上都没有差异, 说明目标语言在语音加工过程中非目标语言的语音层面没有得到自动激活, 从而没有产生启动效应。实验2则设置了语义相关和无关配对词, 并进行语义判断任务, 结果在两种切换条件下都发现明显的语义启动效应及N400差异, 说明非目标语言在语义层面上有得到自动激活, 但激活的程度表现出切换方向上的不一致, L1-L2切换下的语义启动量要明显大于L2-L1, 并且L1-L2的N400差异主要表现在前部脑区, 持续时间更久, 而L2-L1的N400差异主要表现在后部脑区, 但持续时间较短, 表明对于非熟练的双语者来说, 不同切换方向下对共享语义表征的激活加工是不一样的。     

中-英双语者语言理解中非加工语言的自动激活

采用长时重复启动范式探讨母语为汉语的中-英双语者语言理解中非加工语言的激活状况。实验1和实验2使用词汇判断任务, 实验3和实验4使用概念判断任务。在每个实验的第一个小实验中, 非加工语言是英文, 在每个实验的第二个小实验中, 非加工语言是中文。实验1和实验3探讨学习阶段的非加工词在测验阶段呈现时能否出现长时重复启动效应, 从而检验双语者语言理解中非加工语言有没有自动激活; 实验2和实验4探讨学习阶段的非加工词在测验阶段以翻译对等词呈现时能否出现长时重复启动效应, 从而检验双语者语言理解中非加工语言的语义有没有自动激活。总的实验结果表明, 母语为汉语的中-英双语者在语言理解过程中, 加工一种语言(目标语言)时, 非加工语言(要求被试忽略的另一种语言)会自动激活, 但在词汇任务情境中, 非加工语言只在词汇层面上激活, 其语义不会自动激活, 而在概念任务情境中, 非加工语言的词汇层面和语义层面都会自动激活。     

Grammatical Morphemes and Conceptual Structure in Discourse Processing

The present paper analyzes how the semantic and pragmatic functions of closed class categories, or grammatical morphemes (i.e., inflections and function words), organize discourse processing. Grammatical morphemes tend to express a small set of conceptual distinctions that organize a wide range of objects and relations, usually expressed by content or open class words (i.e., nouns and verbs), into situations anchored to a discourse context. Therefore, grammatical morphemes and content words cooperate in guiding the construction of a situation model during discourse comprehension by specifying complementary aspects of described situations. The paper reviews and extends analytical and empirical evidence for this grammatical-conceptual correspondence, and suggests that the correspondence developed in response to the cognitive demands of discourse processing. Thus the distinction between open and closed linguistic categories is interpreted in terms of a fundamental correspondence between conceptual and linguistic structure that helps organize discourse processing.     

汉语惯用语的产生机制

惯用语是固定表达的一种。非构造观点认为, 惯用语已经词汇化, 惯用语理解是提取过程; 构造观点认为, 惯用语意义是建构的, 成分的字面意义对惯用语理解起重要作用。混合模型认为, 惯用语既有整体表征, 又有成分单词表征, 二者都可以成为表征和通达的单元。通过三个实验, 考察了汉语惯用语的产生机制。实验1考察在惯用语产生中是否存在整体表征和成分表征; 实验2考察在惯用语产生中是否存在从成分单词或成分词素表征到整体表征的激活; 实验3考察在惯用语产生中是否存在从整体表征到成分单词或成分词素的激活。结果表明: (1) 汉语惯用语属于混合表征, 既有整体表征, 又有成分单词、成分词素表征; (2)成分词素表征是惯用语整体表征和成分单词表征联结的桥梁; (3) 语义可分性影响惯用语表征。     

The relation between children's conceptual functioning with color and color term acquisition

Young children experience considerable difficulty in learning their first few color terms. One explanation for this difficulty is that initially they lack a conceptual representation of color sufficiently abstract to support word meaning. This hypothesis, that prior to learning color terms children do not represent color as an abstraction, was tested in two experiments using samples of 25- to 39-month-olds and 20- to 32-month-olds. Children's ability to conceptually represent color and their knowledge of color terms were assessed, and a strong association was found between the ability to make inferences based on color and the comprehension of color words. Children who did not comprehend color terms were unsuccessful at a conceptual task that required them to represent color as a property independent of the particular objects that displayed it. The results suggest that the initial absence of an abstract representation of color contributes to the difficulty that young children encounter when first learning color words.     

Neural responses to morphological, syntactic, and semantic properties of single words: an fMRI study

Dissociations in the recognition of specific classes of words have been documented in brain-injured populations. These include deficits in the recognition and production of morphologically complex words as well as impairments specific to particular syntactic classes such as verbs. However, functional imaging evidence for distinctions among the neural systems underlying these dissociations has been inconclusive. We explored the neural systems involved in processing different word classes in a functional Magnetic Resonance Imaging study, contrasting four groups of words co-varying morphological complexity (simple, monomorphemic words vs complex derived or inflected words) and syntactic class (verbs vs nouns/adjectives). Subtraction of word from letter string processing showed activation in left frontal and temporal lobe regions consistent with prior studies of visual word processing. No differences were observed for morphologically complex and simple words, despite adequate power to detect stimulus specific effects. A region of posterior left middle temporal gyrus showed significantly increased activation for verbs. Post hoc analyses showed that this elevated activation could also be related to semantic properties of the stimulus items (verbs have stronger action associations than nouns, and action association is correlated with activation). Results suggest that semantic as well as syntactic factors should be considered when assessing the neural systems involved in single word comprehension.     

The effects of prior knowledge and text structure on comprehension processes during reading of scientific texts

The aim of the present study was to investigate the effects of prior knowledge and text structure on cognitive processes during comprehension of scientific texts. To investigate the processes online, we used a think-aloud methodology in Experiment 1 and a reading time methodology in Experiment 2. In both experiments, we obtained offline comprehension measures and measures of individual differences in working memory and need for cognition. Across the two experiments, the results indicated that readers adjust their processing as a function of the interaction between prior knowledge and text structure. In particular, adjustments in theactual processes that take place during reading were observed for readers who had erroneous prior knowledge,but only when they read a text that was structured to explicitly refute this prior knowledge. Furthermore, the results showed that readers' memory for the text was affected by differences in their prior knowledge, independently of text structure. These findings contribute to our understanding of the relation between different factorsthat are associated with comprehension of scientific texts and have implications for theories of comprehension and conceptual change.     

Feature Statistics Modulate the Activation of Meaning During Spoken Word Processing

Understanding spoken words involves a rapid mapping from speech to conceptual representations. One distributed feature‐based conceptual account assumes that the statistical characteristics of concepts’ features—the number of concepts they occur in (distinctiveness/sharedness) and likelihood of co‐occurrence (correlational strength)—determine conceptual activation. To test these claims, we investigated the role of distinctiveness/sharedness and correlational strength in speech‐to‐meaning mapping, using a lexical decision task and computational simulations. Responses were faster for concepts with higher sharedness, suggesting that shared features are facilitatory in tasks like lexical decision that require access to them. Correlational strength facilitated responses for slower participants, suggesting a time‐sensitive co‐occurrence‐driven settling mechanism. The computational simulation showed similar effects, with early effects of shared features and later effects of correlational strength. These results support a general‐to‐specific account of conceptual processing, whereby early activation of shared features is followed by the gradual emergence of a specific target representation.     

Prose Representation: A Multidimensional Scaling Approach

Multidimensional scaling was employed to study the comprehension of prose. Subjects rated the similarity between pairs of 20 nouns before reading. After reading a passage containing the nouns, the subjects re-rated the words with respect to similarity within the passage. Subjects then recalled the passage. The similarity ratings were analyzed by multidimensional scaling. The results indicated that the scaling analysis provided an effective, valid indicator of prose representation. The multidimensional structural characteristics of dimension interpretation, clustering, and centrality were interpreted in terms of the theme, episodes, and central organizing feature of the story, respectively. Theoretically, the analysis indicated that comprehension was a function of the passage organization mapping onto the existing memory structure superimposed upon and suppressing the prior conceptual structure.     

Capturing conceptual implicit memory: The time it takes to produce an association

Conceptual implicit memory is demonstrated when, in the absence of explicit retrieval, performance on a task requiring conceptual processing benefits more from prior conceptual encoding than from prior nonconceptual encoding. In the present study, we sought to provide an improved measure of conceptual implicit memory by minimizing contamination from explicit retrieval. On a modified word association test, participants free-associated to the actually studied items, with response time to produce any associate serving as the dependent measure. Experiment 1 varied whether words were read or generated at study and showed that generated words were associated to more quickly than were read words. Experiment 2 varied level of processing at study and showed that words processed semantically were associated to more quickly than were words processed nonsemantically. With modifications to ensure its implicit nature, a conceptual implicit test can be consistently affected by the same encoding manipulations as those that affect conceptual explicit memory tests.     

Categorical structure among shared features in networks of early-learned nouns

The shared features that characterize the noun categories that young children learn first are a formative basis of the human category system. To investigate the potential categorical information contained in the features of early-learned nouns, we examine the graph-theoretic properties of noun-feature networks. The networks are built from the overlap of words normatively acquired by children prior to 2½ years of age and perceptual and conceptual (functional) features acquired from adult feature generation norms. The resulting networks have small-world structure, indicative of a high degree of feature overlap in local clusters. However, perceptual features - due to their abundance and redundancy - generate networks more robust to feature omissions, while conceptual features are more discriminating and, per feature, offer more categorical information than perceptual features. Using a network specific cluster identification algorithm (the clique percolation method) we also show that shared features among these early-learned nouns create higher-order groupings common to adult taxonomic designations. Again, perceptual and conceptual features play distinct roles among different categories, typically with perceptual features being more inclusive and conceptual features being more exclusive of category memberships. The results offer new and testable hypotheses about the role of shared features in human category knowledge.     

Embodied emotion concepts: How generating words about pride and disappointment influences posture

Embodiment theories predict that activating conceptual knowledge about emotions can be accompanied by re‐experiencing bodily states, since simulations of sensory, motor, and introspective experiences form the foundation of conceptual representations of emotion. In the present study, we examine whether the activation of the specific emotion concepts of pride and disappointment are embodied in the sense that they are accompanied by changes in posture. Participants generated words associated with pride and disappointment while posture height was measured. Results show that during the generation of disappointment words participants decreased their posture height more than when participants generated pride words. This finding suggests that the activation of conceptual knowledge about disappointment can lead to a spontaneous expression of the associated body posture. In contrast to posture changes along the vertical axis, movement along the horizontal axis was not influenced by concept activation. In addition to bodily simulation the data also indicated introspective simulation, since feelings of disappointment increased after generating disappointment words. The current study provides the first evidence for the claim that the activation of conceptual knowledge about emotion can instantiate spontaneous simulations at a behavioral level. Copyright © 2008 John Wiley & Sons, Ltd.     

语言理解中的动作知觉：基于具身认知的视角

具身认知理论是目前认知科学领域中最新的研究范式和取向, 它认为人的认知过程依赖于感知和动作系统, 强调身体在认知中发挥重要作用。具身语言理解则认为, 身体、动作和知觉系统在语言认知中也起着不可或缺的作用。文章在简要回顾具身语言理解的相关理论如索引假设、浸入式经历者框架、语言神经理论的基础上, 重点从语言理解的四个层面的实证研究, 即音位、单词、句子、语篇, 证实具身语言理解的观点。未来的研究应该着眼于用具身认知观点来解释更高级的抽象语言表征, 具身单词、句子、语篇的具体表征形式, 并利用具身语言认知的观点进行认知的本土化研究。     

Semantic and phonological performance in adults learning novel object and action words

Twenty normal adults participated in two training sessions designed to teach eight novel object words and eight novel action words. Each subject received comprehension and production training and was probed at the end of each session to determine the ability to retrieve lexical items in a naming task. The probe data were also analyzed for phonological accuracy. Reaction time measures for the production probes were recorded to determine differences between action and object words in terms of retrieval difficulty. The results demonstrated a significant difference in early learning of action and object words during comprehension training and production training and in production probes. Object words tended to be learned more easily in both comprehension and production training, and they were retrieved correctly more often in production probes. There were no significant differences in the phonological accuracy between the word types. Reaction time data indicated significant differences in early as well as later learning between action and object words, with object words having significantly shorter rection times as compared with action words. Results are discussed in the context of prior research.     

Mechanisms for accessing lexical representations for output: evidence from a category-specific semantic deficit

We report the performance of a neurologically impaired patient, JJ, whose oral reading of words exceeded his naming and comprehension performance for the same words--a pattern of performance that has been previously presented as evidence for "direct, nonsemantic, lexical" routes to output in reading. However, detailed analyses of JJ's reading and comprehension revealed two results that do not follow directly from the "direct route" hypothesis: (1) He accurately read aloud all orthophonologically regular words and just those irregular words for which he demonstrated some comprehension (as indicated by correct responses or within-category semantic errors in naming and comprehension tasks); and (2) his reading errors on words that were not comprehended at all (but were recognized as words) were phonologically plausible (e.g., soot read as "suit"). We account for these results by proposing that preserved sublexical mechanisms for converting print to sound, together with partially preserved semantic information, serve to mediate the activation of representations in the phonological output lexicon in the task of reading aloud. We present similar arguments for postulating an interaction between sublexical mechanisms and lexical output components of the spelling process.     

Novelty and processing demands in conceptual combination

In this article, we sought to isolate the processing demands of combining the concepts of modifier‐noun phrases from those of other language comprehension processes. Probe reaction time (RT) was used as an indication of the processing resources required for combining concepts. Phrase frequency (as measured by Google hit rates) was used as a metric of the degree of conceptual combination required for each phrase. Participants were asked to interpret modifier‐noun phrases using a sense‐nonsense decision (Experiment 1) and a phrase meaning access task (Experiment 2). Experiment 2 also used a lexical decision task to activate the word's individual meanings. Regression analyses for both experiments indicated that phrase frequency (indicating novelty) predicts a significant portion of the probe RT variance, such that low‐frequency phrases required more processing resources than high‐frequency phrases, when controlling for associative strength, word frequency, letter length, and lexical‐semantic activation. Overall, this study indicates that conceptual combination requires processing resources beyond those of other language processes.     

The embodiment of emotional words in a second language: An eye-movement study

The hypothesis that word representations are emotionally impoverished in a second language (L2) has variable support. However, this hypothesis has only been tested using tasks that present words in isolation or that require laboratory-specific decisions. Here, we recorded eye movements for 34 bilinguals who read sentences in their L2 with no goal other than comprehension, and compared them to 43 first language readers taken from our prior study. Positive words were read more quickly than neutral words in the L2 across first-pass reading time measures. However, this emotional advantage was absent for negative words for the earliest measures. Moreover, negative words but not positive words were influenced by concreteness, frequency and L2 proficiency in a manner similar to neutral words. Taken together, the findings suggest that only negative words are at risk of emotional disembodiment during L2 reading, perhaps because a positivity bias in L2 experiences ensures that positive words are emotionally grounded.     

Regional cerebral blood flow during comprehension and speech (in cerebrally healthy subjects)

Regional cerebral blood flow (rCBF) was measured by the xenon-133 inhalation method in 10 cerebrally healthy subjects at rest and during linguistic activation tests. These consisted of a comprehension test (binaural listening to a narrative text) and a speech test (making sentences from a list of words presented orally at 30-s intervals). The comprehension task induced a moderate increase in the mean right CBF and in both inferior parietal areas, whereas the speech test resulted in a diffuse increase in the mean CBF of both hemispheres, predominating regionally in both inferior parietal, left operculary, and right upper motor and premotor areas. It is proposed that the activation pattern induced by linguistic stimulation depends on not only specific factors, such as syntactic and semantic aspects of language, but also the contents of the material proposed and the attention required by the test situation.     

Adjacent and Non-Adjacent Word Contexts Both Predict Age of Acquisition of English Words: A Distributional Corpus Analysis of Child-Directed Speech

Children show a remarkable degree of consistency in learning some words earlier than others. What patterns of word usage predict variations among words in age of acquisition? We use distributional analysis of a naturalistic corpus of child-directed speech to create quantitative features representing natural variability in word contexts. We evaluate two sets of features: One set is generated from the distribution of words into frames defined by the two adjacent words. These features primarily encode syntactic aspects of word usage. The other set is generated from non-adjacent co-occurrences between words. These features encode complementary thematic aspects of word usage. Regression models using these distributional features to predict age of acquisition of 656 early-acquired English words indicate that both types of features improve predictions over simpler models based on frequency and appearance in salient or simple utterance contexts. Syntactic features were stronger predictors of children's production than comprehension, whereas thematic features were stronger predictors of comprehension. Overall, earlier acquisition was predicted by features representing frames that select for nouns and verbs, and by thematic content related to food and face-to-face play topics; later acquisition was predicted by features representing frames that select for pronouns and question words, and by content related to narratives and object play.