A Principled Approach to Feature Selection in Models of Sentence Processing

Among theories of human language comprehension, cue-based memory retrieval has proven to be a useful framework for understanding when and how processing difficulty arises in the resolution of long-distance dependencies. Most previous work in this area has assumed that very general retrieval cues like [+subject] or [+singular] do the work of identifying (and sometimes misidentifying) a retrieval target in order to establish a dependency between words. However, recent work suggests that general, handpicked retrieval cues like these may not be enough to explain illusions of plausibility (Cunnings & Sturt, 2018), which can arise in sentences like The letter next to the porcelain plate shattered. Capturing such retrieval interference effects requires lexically specific features and retrieval cues, but handpicking the features is hard to do in a principled way and greatly increases modeler degrees of freedom. To remedy this, we use well-established word embedding methods for creating distributed lexical feature representations that encode information relevant for retrieval using distributed retrieval cue vectors. We show that the similarity between the feature and cue vectors (a measure of plausibility) predicts total reading times in Cunnings and Sturt’s eye-tracking data. The features can easily be plugged into existing parsing models (including cue-based retrieval and self-organized parsing), putting very different models on more equal footing and facilitating future quantitative comparisons.     

Misinterpretations of Garden-Path Sentences: Implications for Models of Sentence Processing and Reanalysis

Theories of sentence comprehension have addressed both initial parsing processes and mechanisms responsible for reanalysis. Three experiments are summarized that were designed to investigate the reanalysis and interpretation of relatively difficult garden-path sentences (e.g., While Anna dressed the baby spit up on the bed). After reading such sentences, participants correctly believed that the baby spit up on the bed; however, they often confidently, yet incorrectly, believed that Anna dressed the baby. These results demonstrate that garden-path reanalysis is not an all-or-nothing process and that thematic roles initially assigned for the subordinate clause verb are not consistently revised. The implications of the partial reanalysis phenomenon for Fodor and Inoue's (1998) model of reanalysis and sentence processing are discussed. In addition, we discuss the possibility that language processing often creates good enough structures rather than ideal structures.     

A Computational Evaluation of Two Models of Retrieval Processes in Sentence Processing in Aphasia

Can sentence comprehension impairments in aphasia be explained by difficulties arising from dependency completion processes in parsing? Two distinct models of dependency completion difficulty are investigated, the Lewis and Vasishth (2005) activation-based model and the direct-access model (DA; McElree, 2000). These models' predictive performance is compared using data from individuals with aphasia (IWAs) and control participants. The data are from a self-paced listening task involving subject and object relative clauses. The relative predictive performance of the models is evaluated using k-fold cross-validation. For both IWAs and controls, the activation-based model furnishes a somewhat better quantitative fit to the data than the DA. Model comparisons using Bayes factors show that, assuming an activation-based model, intermittent deficiencies may be the best explanation for the cause of impairments in IWAs, although slowed syntax and lexical delayed access may also play a role. This is the first computational evaluation of different models of dependency completion using data from impaired and unimpaired individuals. This evaluation develops a systematic approach that can be used to quantitatively compare the predictions of competing models of language processing.     

Wide-Coverage Probabilistic Sentence Processing

This paper describes a fully implemented, broad-coverage model of human syntactic processing. The model uses probabilistic parsing techniques, which combine phrase structure, lexical category, and limited subcategory probabilities with an incremental, left-to-right pruning mechanism based on cascaded Markov models. The parameters of the system are established through a uniform training algorithm, which determines maximum-likelihood estimates from a parsed corpus. The probabilistic parsing mechanism enables the system to achieve good accuracy on typical, garden-variety language (i.e., when tested on corpora). Furthermore, the incremental probabilistic ranking of the preferred analyses during parsing also naturally explains observed human behavior for a range of garden-path structures. We do not make strong psychological claims about the specific probabilistic mechanism discussed here, which is limited by a number of practical considerations. Rather, we argue incremental probabilistic parsing models are, in general, extremely well suited to explaining this dual nature—generally good and occasionally pathological—of human linguistic performance.     

Connectionist Sentence Processing in Perspective

The emphasis in the connectionist sentence-processing literature on distributed representation and emergence of grammar from such systems can easily obscure the often close relations between connectionist and symbolist systems. This paper argues that the Simple Recurrent Network (SRN) models proposed by Jordan (1989) and Elman (1990) are more directly related to stochastic Part-of-Speech (POS) Taggers than to parsers or grammars as such, while auto-associative memory models of the kind pioneered by Longuet–Higgins, Willshaw, Pollack and others may be useful for grammar induction from a network-based conceptual structure as well as for structure-building. These observations suggest some interesting new directions for specifically connectionist sentence processing research, including more efficient representations for finite state machines, and acquisition devices based on a distinctively connectionist basis for grounded symbolist conceptual structure.     

Attention in Sentence Processing: A Review

This review looks at the relationship between attention and language. There have been many studies that have shown a certain role of attention on sentence and spoken word processing. At the same time some other studies have observed that language processing is autonomous. In this review an attempt has been made to review the empirical evidence from sentence processing in reading, auditory processing and speaking domains to see if attentional manipulations cause interference with processing. The review suggests currently available evidence is rather mixed and it is still a long way to fully explore the attentional basis of sentence processing.     

Incrementality and Prediction in Human Sentence Processing

We identify a number of principles with respect to prediction that, we argue, underpin adult language comprehension: (a) comprehension consists in realizing a mapping between the unfolding sentence and the event representation corresponding to the real-world event being described; (b) the realization of this mapping manifests as the ability to predict both how the language will unfold, and how the real-world event would unfold if it were being experienced directly; (c) concurrent linguistic and nonlinguistic inputs, and the prior internal states of the system, each drive the predictive process; (d) the representation of prior internal states across a representational substrate common to the linguistic and nonlinguistic domains enables the predictive process to operate over variable time frames and variable levels of representational abstraction. We review empirical data exemplifying the operation of these principles and discuss the relationship between prediction, event structure, thematic role assignment, and incrementality.     

Activating Basic Category Exemplars in Sentence Contexts: A Dynamical Account

This paper examines the influence of context on the processing of category names embedded in sentences. The investigation focuses on the nature of information available immediately after such a word is heard as well as on the dynamics of adaptation to context. An on-line method (Cross Modal Lexical Priming) was used to trace how this process unfolds in time. We found that the information available immediately after a category word is presented is not altered by the sentence context in which the word is immersed. Rather, the structure of availability of particular exemplars of the category resembles the typicality structure of a conceptual representation. The adaptation to context occurs later (between 300 and 450 ms after the category word) and takes the form of a rapid reorganization of the structure rather than a gradual activation of a contextually relevant exemplar. We claim that such data is best accounted for in a dynamical framework, where a coherent global structure emerges through locally guided self-organization.     

句子加工中的语义P600效应

句子加工领域的研究中,一般认为,N400效应与语义加工有关,句法违反通常引发P600效应。然而近年来一些研究发现,句子语义违反时也引发了P600效应,即语义P600效应。对语义P600效应的诱发原因及其功能意义,目前有三种代表性的解释:监控说认为,P600效应是由语言理解过程中的认知冲突引发的,反映了认知监控系统对可能出现的加工错误的检测与解决;而非句法中心动态模型认为语义P600效应反映的是句子理解过程中两条通路之间出现冲突时的持续分析;扩展的论元依赖模型则用新的句子加工模型来解释语义P600效应,认为语义P600效应与句法违反引发的P600效应产生于句子加工的不同过程。     

A Computational Evaluation of Sentence Processing Deficits in Aphasia

Individuals with agrammatic Broca's aphasia experience difficulty when processing reversible non‐canonical sentences. Different accounts have been proposed to explain this phenomenon. The Trace Deletion account (Grodzinsky, 1995, 2000, 2006) attributes this deficit to an impairment in syntactic representations, whereas others (e.g., Caplan, Waters, Dede, Michaud, & Reddy, 2007; Haarmann, Just, & Carpenter, 1997) propose that the underlying structural representations are unimpaired, but sentence comprehension is affected by processing deficits, such as slow lexical activation, reduction in memory resources, slowed processing and/or intermittent deficiency, among others. We test the claims of two processing accounts, slowed processing and intermittent deficiency, and two versions of the Trace Deletion Hypothesis (TDH), in a computational framework for sentence processing (Lewis & Vasishth, 2005) implemented in ACT‐R (Anderson, Byrne, Douglass, Lebiere, & Qin, 2004). The assumption of slowed processing is operationalized as slow procedural memory, so that each processing action is performed slower than normal, and intermittent deficiency as extra noise in the procedural memory, so that the parsing steps are more noisy than normal. We operationalize the TDH as an absence of trace information in the parse tree. To test the predictions of the models implementing these theories, we use the data from a German sentence—picture matching study reported in Hanne, Sekerina, Vasishth, Burchert, and De Bleser (2011). The data consist of offline (sentence‐picture matching accuracies and response times) and online (eye fixation proportions) measures. From among the models considered, the model assuming that both slowed processing and intermittent deficiency are present emerges as the best model of sentence processing difficulty in aphasia. The modeling of individual differences suggests that, if we assume that patients have both slowed processing and intermittent deficiency, they have them in differing degrees.     

第二语言句子加工的ERP研究

研究者对第一语言句子加工的事件相关电位(ERP)进行研究,提出了句子加工三阶段模型及对应的ERP成分。第二语言(L2)句子加工的ERP研究结果很不一致。首先,从句子加工的ERP反应模式上来看,大多数研究发现L2学习者的ERP反应模式和母语者有质的差异,少数研究发现L2学习者加工L2句子的ERP模式类似母语者,但其反应的时间进程、波幅或分布与母语者有显著差异。被试的学习年龄、熟练程度以及学习者的两种语言的相似性程度可能是影响第二语言句子加工ERP反应的主要因素。     

Sentence Comprehension Deficits in Alzheimer''s Disease: A Comparison of Off-Line vs. On-Line Sentence Processing

Two studies explored whether sentence comprehension impairments in Alzheimer's disease (AD) are due to deficits in syntactic processing or memory. Study 1 used a picture-pointing sentence comprehension task to measure the final outcome of comprehension in an off-line fashion. It showed the comprehension of 30 patients with AD to be impaired, but suggested that the deficits could not be attributed solely to syntactic impairments. Study 2 investigated the effects of memory on sentence comprehension by comparing off-line (grammaticality judgment) with on-line (cross-modal naming) language processing in 11 AD and 9 control subjects. The results revealed impaired performance in the off-line task but normal performance in the on-line task using the same sentences. Performance on the off-line task correlated with independent measures of verbal working memory. These data are used to argue that sentence comprehension impairments are related to verbal working memory deficits in AD.     

句子理解过程中词类加工的功能性质

句法优先理论假设词类加工功能上优先于语义、动词论元结构和话语信息加工。来自德语和法语的证据显示, 词类违反阻断语义整合和动词论元结构加工, 因而词类优先于语义和动词论元结构。关于词类加工在功能上是否优先于话语信息加工, 尚无来自任何语言的证据。汉语证据尽管显示词类并不优先于语义, 但未充分讨论任务因素的影响。将来研究有必要使用ERP技术和违反范式, 从语义整合、动词论元结构加工和话语水平加工等多个层面, 同时操纵词类的正确性和非句法因素, 考察句法特性上与德语和法语不同的语言, 如汉语和韩语。这方面研究将有助于洞察一个语言的语言学特性如何制约或调整词类加工的功能性质。     

生命性在句子加工中作用的ERP研究

生命性广泛地渗透到人类语言系统中发挥其作用。本文主要结合最新和经典的有关生命性的ERP研究探讨了生命性信息起作用的模式和时间进程。在句子加工过程中,生命性影响论元的加工并影响题元结构的建构和解释。以往研究表明,生命性违反有时引发的是N400效应,有时引发的是P600效应,少数情况还表现出N400-P600的双相模式。生命性在句子加工中的作用还跟多种变量存在交互作用,语境、题元可逆性、论元之间的语义关系、动词类型和其固有的题元结构都可能影响生命性信息起作用的模式。文章最后进行总结和展望,并提出未来研究仍有必要继续探讨生命性信息加工的时间神经动态性及其在句子加工中的具体作用机制。     

Comprehension Models of Audiovisual Discourse Processing

Comprehension is integral to enjoyment of media narratives, yet our understanding of how viewers create the situation models that underlie comprehension is limited. This study utilizes two models of comprehension that had previously been tested with factual texts/videos to predict viewers' recall of entertainment media. Across five television/film clips, the landscape model explained at least 29% of the variance in recall. A dual coding version that assumed separate verbal and visual representations of the story significantly improved the model fit in four of the clips, accounting for an additional 15–29% of the variance. The dimensions of the event‐indexing model (time, space, protagonist, causality, and intentionality) significantly moderated the relationship between the dual coding model and participant recall in all clips.     

句子理解过程中句法与语义加工的EEG时频分析

EEG时频分析旨在通过测量单个电极各频段的能量变化, 揭示事件相关振荡活动。采用该技术, 最近的句子加工研究发现, 句法与语义过程均与多个频段(θ、a、b或γ)能量变化相联系。此外, 不同方面的句法(如语法性、数)和语义加工(语义整合或预期)与不同频段振荡活动相联系。将来的研究应该使用多种EEG能量计算方法, 在多种语言中, 探讨时态、词序等句法加工所伴随的振荡活动, 特别是句法和语义过程相互作用在EEG能量变化上的表现。