Towards a neural basis of auditory sentence processing

Functional dissociations within the neural basis of auditory sentence processing are difficult to specify because phonological, syntactic and semantic information are all involved when sentences are perceived. In this review I argue that sentence processing is supported by a temporo-frontal network. Within this network, temporal regions subserve aspects of identification and frontal regions the building of syntactic and semantic relations. Temporal analyses of brain activation within this network support syntax-first models because they reveal that building of syntactic structure precedes semantic processes and that these interact only during a later stage.     

句法预测对句子理解影响的眼动实验

实验采用眼动技术实时考察了句子阅读理解过程中的句法预测效应和并列句的结构表征特点。眼动数据分析发现：(1)有无句法预测没有明显影响名词短语区域的加工, 不同眼动指标差异不显著; (2)有无句法预测显著影响被试对包含暂时局部歧义的关键区和具有解歧作用的关键后区域的阅读理解, 首次注视时间、第一遍阅读时间、回视路径时间和第一遍回视率明显减少。眼动研究表明, 暂时局部歧义句子阅读理解过程中表现出明显的句法预测效应, 有句法预测降低了局部歧义区域和解歧区域早期和晚期加工的难度; 和英语的短语并列优先法则不同, 汉语并列句子的结构表征出现分离现象, 即短语并列和句子并列。     

Ambiguity in the brain: what brain imaging reveals about the processing of syntactically ambiguous sentences

Two fMRI studies investigated the time course and amplitude of brain activity in language-related areas during the processing of syntactically ambiguous sentences. In Experiment 1, higher levels of activation were found during the reading of unpreferred syntactic structures as well as more complex structures. In Experiments 2A and 2B higher levels of brain activation were found for ambiguous sentences compared with unambiguous sentences matched for syntactic complexity, even when the ambiguities were resolved in favor of the preferred syntactic construction (despite the absence of this difference in previous reading time results). Although results can be reconciled with either serial or parallel models of sentence parsing, they arguably fit better into the parallel framework. Serial models can admittedly be made consistent but only by including a parallel component. The fMRI data indicate the involvement of a parallel component in syntactic parsing that might be either a selection mechanism or a construction of multiple parses.     

加工速度对晚期第二语言学习者句法加工的影响

两个实验通过操纵句子呈现的速度,考察加工速度因素对于晚期第二语言学习者句法加工的影响。实验1采用视觉方式呈现句子,实验2采用听觉方式呈现句子。被试的母语为汉语,第二语言为英语,属于晚期第二语言学习者,实验任务为句法判断。两个实验的结果表明,加工速度缓慢是导致晚期第二语言学习者句法加工困难的重要因素之一。加工速度缓慢对第二语言句法加工的影响,不是局限于少数一两种句法形式,而是作用于多数句法形式。研究还发现,视觉和听觉两种呈现方式下,不同句法形式的加工难度既存在共性的一面,也存在差异性的一面。     

中文句子中双音节兼类词句法分析历程初探

以既可用作名词,又可用作动词的汉语双音节兼类词为材料,采用移动窗口范式,考察了汉语句子中名词倾向性高和低两类兼类词句法分析的详细历程。结果发现,两类兼类词与各自的控制词之间,均未出现阅读时间上的显著差异,因此并不支持延迟模型所提出的兼类词句法角色延迟指派的观点。实验还发现,名词倾向性高的兼类词引起了更大的加工困难。此外,即便是名词倾向性低的兼类词,被试也仍为其指派名词的句法角色。花园路径模型和制约满意理论均不能单独和完整解释上述发现。文章指出,实验结果支持一种既不同于花园路径模型,又不同于制约满意理论的权变的理论。阅读中遇到兼类词时,读者能立即为其指派句法角色。这种指派过程既可以利用概率制约信息,也可以在句法分析原则指导下进行。句法分析原则是否起作用,取决于概率制约信息的制约强度     

Syntactic priming and the lexical boost effect during sentence production and sentence comprehension: An fMRI study

Behavioral syntactic priming effects during sentence comprehension are typically observed only if both the syntactic structure and lexical head are repeated. In contrast, during production syntactic priming occurs with structure repetition alone, but the effect is boosted by repetition of the lexical head. We used fMRI to investigate the neuronal correlates of syntactic priming and lexical boost effects during sentence production and comprehension. The critical measure was the magnitude of fMRI adaptation to repetition of sentences in active or passive voice, with or without verb repetition. In conditions with repeated verbs, we observed adaptation to structure repetition in the left IFG and MTG, for active and passive voice. However, in the absence of repeated verbs, adaptation occurred only for passive sentences. None of the fMRI adaptation effects yielded differential effects for production versus comprehension, suggesting that sentence comprehension and production are subserved by the same neuronal infrastructure for syntactic processing.     

Dissociation of algorithmic and heuristic processes in language comprehension: Evidence from aphasia

Three groups of aphasic patients, Broca's, Conduction, and Wernicke's, and a nonaphasic patients control group were tested for comprehension of object-relative center-embedded sentences. The sentences were of three types: sentences in which semantic constraints between words allowed the subjects to assign a correct semantic reading of the sentence without decoding the syntax, sentences in which semantic constraints were relaxed and for which a correct reading was only possible with knowledge of syntactic relationships among words, and sentences which described highly improbable events. The subjects' task was to choose which of two pictures captured the meaning expressed in the sentence. Broca's and Conduction aphasics performed near perfectly on sentences where they could use semantic information. Their performance dropped to chance when they had to use syntactic information. These results support a neuropsychological dissociation of heuristic and algorithmic processes based primarily, though not exclusively, on semantic and syntactic information, respectively.     

Syntactic prediction in language comprehension: evidence from either...or

Readers' eye movements were monitored as they read sentences in which two noun phrases or two independent clauses were connected by the word or (NP-coordination and S-coordination, respectively). The word either could be present or absent earlier in the sentence. When either was present, the material immediately following or was read more quickly, across both sentence types. In addition, there was evidence that readers misanalyzed the S-coordination structure as an NP-coordination structure only when either was absent. The authors interpret the results as indicating that the word either enabled readers to predict the arrival of a coordination structure; this predictive activation facilitated processing of this structure when it ultimately arrived, and in the case of S-coordination sentences, enabled readers to avoid the incorrect NP-coordination analysis. The authors argue that these results support parsing theories according to which the parser can build predictable syntactic structure before encountering the corresponding lexical input.     

Developmental changes in units of processing in reading

A visual search task was used to investigate the development of word processing skills used in reading meaningful prose. Children from the second and fourth grades and college students were asked to locate a prespecified letter, syllable, word, or category exemplar as they read through sentences. Target detection time, sentence reading time, and sentence comprehension were measured. The results provide converging evidence that whole words were the preferred units of processing during reading for all three grade levels. Reading rates for sentences in the word search condition were comparable to normal reading rates. The search for smaller units required additional processing time, but word and category search times differed only for the youngest subjects.     

Lexically independent priming in online sentence comprehension

Two eye-tracking experiments investigated what happens when people read pairs of sentences that have the same syntactic structure. Previous experiments have shown priming in online sentence processing only when critical lexical material overlaps between the prime and the target sentence. In the current study, participants were asked to read sentences containing modifier—goal ambiguities. Half of the target sentences were preceded by sentences with the same structure, and half were preceded by sentences with a different structure. In Experiment 1, the prime—target pairs had the same main verb. In Experiment 2, the prime—target pairs had different main verbs. Facilitated target sentence processing was observed in both Experiments 1 and 2 when the target sentences were preceded by a prime sentence with the same syntactic structure. These results provide the first evidence of lexically independent, between-sentence structural priming in online sentence comprehension.     

The influence of prosodic structure on the resolution of temporary syntactic closure ambiguities

This paper investigates the influence of prosodic structure on the process of sentence comprehension, with a specific focus on the relative contributions of syntactic and prosodic information to the resolution of temporary syntactic closure ambiguities. We argue that prosodic structure provides an initial memory representation for spoken sentences, and that information from this prosodic representation is available to inform syntactic parsing decisions. This view makes three predictions for the processing of temporary syntactic ambiguity: 1. When prosodic and syntactic boundaries coincide, syntactic processing should be facilitated. 2. When prosodic boundaries are placed at misleading points in syntactic structure, syntactic processing should show interference effects. 3. The processing difficulties that have been reliably demonstrated in reading experiments for syntactically complex sentences should disappear when those sentences are presented with a felicitous prosodic structure in listening experiments. These predictions were confirmed by series of experiments measuring end-of-sentence comprehension time and cross-modal naming time for sentences with temporary syntactic closure ambiguities. Sentences with coinciding or conflicting prosodic and syntactic boundaries were compared to a prosodic baseline condition.This research was supported in part by NIMH grant R29 MH51768 to the first author and NIMH grant T32 MH19729 to the Northeastern University Psychology Department.     

The Advantage of First Mention in Korean The Temporal Contributions of Syntactic,Semantic, and Pragmatic Factors

Using Korean, we investigated how syntactic, semantic, and pragmatic factors influence the representation of a sentence, in particular, the relative accessibility of different components of a sentence representation. In six experiments, participants performed a probe recognition task after reading each of a series of sentences. We manipulated the rate at which each word of the sentence was presented (250 ms and 500 ms) and the interval between the sentence-final word and the probe-recognition test word (immediate, 500 ms delay, and 1000 ms delay). We also manipulated the syntactic position (subject versus object), semantic role (agent versus patient), and order of mention (first-versus second-mentioned participant) of the probed item. Pragmatic factors (the order of mention) strongly influenced accessibility immediately and through the longest delay, whereas syntactic and semantic factors had little effect.     

Syntactic processing of Hebrew sentences in normal and dyslexic readers: electrophysiological evidence

The authors examined differences in brain activity as measured by amplitudes and latencies of event-related potential (ERP) components in Hebrew-speaking adult dyslexic and normal readers. The participants were measured while processing words' syntactic functions during reading of sentences with subject-verb-object syntactic order. The results suggested that among dyslexic and normal readers, N100 and P300 ERP components were sensitive to certain constituents of syntactic analysis for target words in accordance with their grammatical roles. The findings further demonstrated significant differences in ERP measures between dyslexic and normal readers. Compared with normal readers, dyslexic readers exhibited consistently higher amplitudes and longer latencies in both ERP components for the subject of the sentence. Significant, though less consistent, ERP variations were observed for other sentence elements. In addition, dyslexic readers differed from normal readers in their processing strategies. For normal readers, the verb-oriented, morphologically based strategy was found to be the most efficient for sentence processing in Hebrew, whereas the dyslexic readers demonstrated a more primitive mode of identification of words' grammatical roles, namely, the word-order strategy. The results support the hypothesis that there is a syntactic processing "weakness" in dyslexics.     

Effects of accelerated reading rate on syntactic processing of Hebrew sentences: electrophysiological evidence

The present study was designed to investigate whether accelerated reading rate influences the way adult readers process sentence components with different grammatical functions. Participants were 20 male native Hebrew-speaking college students aged 18-27 years. The processing of normal word strings was examined during word-by-word reading of sentences having subject-verb-object (SVO) syntactic structure in self-paced and fast-paced conditions. In both reading conditions, the N100 (late positive) and P300 (late negative) event-related potential (ERP) components were sensitive to such internal processes as recognition of words' syntactic functions. However, an accelerated reading rate influenced the way in which readers processed these sentence elements. In the self-paced condition, the predicate-centered (morphologically based) strategy was used, whereas in the fast-paced condition an approach that was more like the word-order strategy was used. This new pattern was correlated with findings on the shortening of latency and the increasing of amplitudes in both N100 and P300 ERP components for most sentence elements. These changes seemed to be related to improved working memory functioning and maximized attention.     

晚期汉-英二语者英语被动句句法加工的ERP研究*

选取二语中等熟练者和高熟练者两类中国大学生被试,共40人(27女,13男),年龄为20~29岁,平均年龄23.88岁。采用ERP技术,以直译型英语被动句和意译型英语被动句作为实验材料,通过比较无违例、―句法违例句1‖(动词过去分词形式错误)、―句法违例句2‖(动词过去分词错误用为动词原形而造成的句法违例)以及―句法违例句3‖(动词过去分词误用为动词现在分词形式)条件下的行为数据和ERP多维数据变化的基础上,探讨了二语熟练度和语言间句法结构相似性对汉-英双语者英语被动句句法加工过程的影响。结果表明：高熟练者的反应时和正确率整体上优于中等熟练者;难易度不同的句法错误信息会直接影响被动句的加工,对明显有错误的句法信息的反应速度最快,―正确的局部句法信息‖反应时最长。对明显有错误的句法信息的正确反应率最高,最根本的句法结构的错误信息最低。最根本的句法结构的错误信息引发的P600最大,无违例条件引发的P600最小;高熟练者对最根本的句法结构的错误信息引发最大的P600效应,中等熟练者的P600效应未受不同句法错误信息的影响。行为指标支持句法加工相似性效应——直译句反应快、正确率高;意译句反应慢、正确率低。并且此效应在中等熟练者身上表现更加明显。但是脑神经活动模式未表现出句法结构相似性效应,说明二语熟练度在英语被动句加工中具有更为显著的作用。     

Readers' Eye Movements Distinguish Anomalies of Form and Content

Evidence is presented that eye-movement patterns during reading distinguish costs associated with the syntactic processing of sentences from costs associated with relating sentence meaning to real world probabilities. Participants (N = 30) read matching sets of sentences that differed by a single word, making the sentence syntactically anomalous (but understandable), pragmatically anomalous, or non-anomalous. Syntactic and pragmatic anomaly each caused perturbations in eye movements. Subsequent to the anomaly, the patterns diverged. Syntactic anomaly generated many regressions initially, with rapid return to baseline. Pragmatic anomaly resulted in lengthened reading times, followed by a gradual increase in regressions that reached a maximum at the end of the sentence. Evidence of rapid sensitivity to pragmatic information supports the use of timing data in resolving the debate over the autonomy of linguistic processing. The divergent patterns of eye movements support indications from neurocognitive studies of a principled distinction between syntactic and pragmatic processing procedures within the language processing mechanism.     

Building syntactic structures in speaking: a bilingual exploration

In a series of three experiments we investigated syntactic priming using a sentence recall task. Participants read and memorized a target sentence for later recall. After reading a prime sentence and engaging in a distraction task, they were asked to produce the target sentence aloud. Earlier investigations have shown that this task is sensitive to a syntactic priming effect. That is, the syntactic form of the prime sentence sometimes influences the syntactic form of the recalled target. In this paper we report on a variation on this task, using Spanish-English bilingual participants. In the first two experiments we replicated the prepositional phrase priming effect using English target sentences and Spanish prime sentences. In the final experiment we investigated two additional syntactic forms, using Spanish target sentences and English prime sentences. Implications for models of syntax generation and bilingual speech production are discussed.     

Syntactic Processing of Hebrew Sentences in Normal and Dyslexic Readers: Electrophysiological Evidence

The authors examined differences in brain activity as measured by amplitudes and latencies of event-related potential (ERP) components in Hebrew-speaking adult dyslexic and normal readers. The participants were measured while processing words' syntactic functions during reading of sentences with subject-verb-object syntactic order. The results suggested that among dyslexic and normal readers, N100 and P300 ERP components were sensitive to certain constituents of syntactic analysis for target words in accordance with their grammatical roles. The findings further demonstrated significant differences in ERP measures between dyslexic and normal readers. Compared with normal readers, dyslexic readers exhibited consistently higher amplitudes and longer latencies in both ERP components for the subject of the sentence. Significant, though less consistent, ERP variations were observed for other sentence elements. In addition, dyslexic readers differed from normal readers in their processing strategies. For normal readers, the verb-oriented, morphologically based strategy was found to be the most efficient for sentence processing in Hebrew, whereas the dyslexic readers demonstrated a more primitive mode of identification of words' grammatical roles, namely, the word-order strategy. The results support the hypothesis that there is a syntactic processing “weakness” in dyslexics.     

On-line processing of topic structure by children and adults

A recent model of text processing proposed that adults construct a representation of topics during reading; a new topic is related to the representation as soon as relevant information is encountered. The present experiment tested the generality of this model for younger readers. Fourth- and sixth-grade children and college students read two hierarchically organized expository texts while reading times were recorded for initial topic sentences and specific nontopic sentences. Across ages, the major findings were (1) topic sentence reading times were shorter if a transition question informed the reader of the next topic; (2) topic sentence reading times were shorter if the new topic was directly related to the immediately preceding topic than if it was not directly related. Reading times for nontopic sentences were not affected by these manipulations. Reading times decreased as age increased, but text structure manipulations had very similar effects at all ages. The results are consistent with the general model, indicating that even young readers identify and relate expository text topics as they read.