Study Of Sentence Comprehension Research Articles

FN400 and LPC Responses to Different Degrees of Sensory Involvement: A Study of Sentence Comprehension.

The current study tested the likely effect of sensory involvement on the FN400 and late positive complex (LPC) responses to semantic and pragmatic comprehension of English sentences. Fifteen English language learners took part in the event-related potential (ERP) experiment and determined the acceptability of 432 sentences under congruent, semantically incongruent, and pragmatically incongruent conditions. Prior to the ERP recording, the subjects received different sensory instructions for six vocabulary items about which they had no previous knowledge. No sensory instruction was given for three extra words, and these served as the control group. The behavioral data corroborated that integration of more senses in instruction improved learners’ pragmatic comprehension. The ERP data revealed that full sensory involvement (involvement) reduced the FN400 amplitude, facilitating real world knowledge retrieval and pragmatic comprehension. The LPC responses to semantic comprehension showed that learners reanalyzed the sentences instructed through limited sensory involvement (exvolvement) more deeply.

Functional significance of the semantic P600: evidence from the event-related brain potential source localization.

Previous event-related potentials studies of sentence comprehension have usually associated syntactic repair/reanalysis processes with the P600 component. However, the functional significance of the P600 was recently questioned on the basis of the observation of P600 effects in response to the processing of semantically anomalous sentences. In the present study, we investigated the functional significance of the 'semantic P600' using a semantic violation paradigm with a focus-on-syntax instruction. Using a source localization analysis, we tested three alternative hypotheses on the function of the P600: (i) a syntactic function, (ii) an executive function, and (iii) a semantic/integrational function. We assumed that distinct neuronal generators should reflect each of these functions. Although the syntactic generators are expected to be mainly located in the left inferior frontal gyrus, the semantic generators should be observed in the left superior temporal gyrus as well as in the right anterior prefrontal cortex (semantic retrieval); moreover, the generator of executive function (conflict monitoring) should be found in the anterior cingulate cortex. Critically, we defined a dipole model using 17 dipoles, 14 of which were placed in the three regions of interest corresponding to our hypotheses, namely, syntactic, executive, and semantic regions. Our data showed that the P600 effect was significant in the anterior cingulate cortex and marginally significant in the right anterior prefrontal cortex. This finding suggests that the P600 might reflect more general mechanisms of conflict monitoring and semantic reinterpretation leading to a retrieval of world knowledge from long-term memory rather purely syntactic processes.

'Syntactic Perturbation' During Production Activates the Right IFG, but not Broca's Area or the ATL.

Research on the neural organization of syntax – the core structure-building component of language – has focused on Broca’s area and the anterior temporal lobe (ATL) as the chief candidates for syntactic processing. However, these proposals have received considerable challenges. In order to better understand the neural basis of syntactic processing, we performed a functional magnetic resonance imaging experiment using a constrained sentence production task. We examined the BOLD response to sentence production for active and passive sentences, unstructured word lists, and syntactic perturbation. Perturbation involved cued restructuring of the planned syntax of a sentence mid utterance. Perturbation was designed to capture the effects of syntactic violations previously studied in sentence comprehension. Our experiment showed that Broca’s area and the ATL did not exhibit response profiles consistent with syntactic operations – we found no increase of activation in these areas for sentences > lists or for perturbation. Syntactic perturbation activated a cortical-subcortical network including robust activation of the right inferior frontal gyrus (RIFG). This network is similar to one previously shown to be involved in motor response inhibition. We hypothesize that RIFG activation in our study and in previous studies of sentence comprehension is due to an inhibition mechanism that may facilitate efficient syntactic restructuring.

An fMRI study dissociating distance measures computed by Broca's area in movement processing: clause boundary vs. identity

Behavioral studies of sentence comprehension suggest that processing long-distance dependencies is subject to interference effects when Noun Phrases (NP) similar to the dependency head intervene in the dependency. Neuroimaging studies converge in localizing such effects to Broca's area, showing that activity in Broca's area increases with the number of NP interveners crossed by a moved NP of the same type. To test if NP interference effects are modulated by adding an intervening clause boundary, which should by hypothesis increase the number of successive-cyclic movements, we conducted an fMRI study contrasting NP interveners with clausal (CP) interveners. Our design thus had two components: (I) the number of NP interveners crossed by movement was parametrically modulated; (II) CP-intervention was contrasted with NP-intervention. The number of NP interveners parametrically modulated a cluster straddling left BA44/45 of Broca's area, replicating earlier studies. Adding an intervening clause boundary did not significantly modulate the size of the NP interference effect in Broca's area. Yet, such an interaction effect was observed in the Superior Frontal Gyrus (SFG). Therefore, the involvement of Broca's area in processing syntactic movement is best captured by memory mechanisms affected by a grammatically instantiated type-identity (i.e., NP) intervention.

EXPERIMENTAL DESIGNS IN SENTENCE PROCESSING RESEARCH

Since the publication of Clahsen and Felser’s (2006) keynote article on grammatical processing in language learners, the online study of sentence comprehension in adult second language (L2) learners has quickly grown into a vibrant and prolific subfield of SLA. As online methods begin to establish a foothold in SLA research, it is important that researchers in our field design sentence-comprehension experiments that adhere to the fundamental principles of research design typical of sentence processing studies published in related subfields of the language sciences. In this article, we discuss and review widely accepted principles of research design for sentence processing studies that are not always followed in L2 sentence processing research. Particular emphasis is placed on the design of experimental items and distractors, the choice and design of the poststimulus distractor task, procedures for presenting stimuli to participants, and methods for trimming and analyzing online data, among others.

Verb transitivity bias affects on-line sentence reading in people with aphasia

Background: Studies of sentence comprehension in non-disordered populations have convincingly demonstrated that probabilistic cues influence on-line syntactic processing. One well-studied cue is verb argument structure bias, which refers to the probability that a verb will occur in a particular syntactic frame. According to the Lexical Bias Hypothesis people with aphasia have difficulty understanding sentences in which the verb's argument structure bias conflicts with the sentence structure (e.g., a transitively biased verb in an intransitive sentence). This hypothesis may provide an account of why people with aphasia have difficulty understanding both simple and complex sentences. Aims: The purpose of this study was to test the Lexical Bias Hypothesis using an on-line measure of written sentence comprehension, self-paced reading. Methods & Procedures: The participants were 10 people with aphasia and 10 non-brain-damaged controls. The stimuli were syntactically simple transitive and intransitive sentences that contained transitively or intransitively biased verbs. For example, the transitively biased verb “called” appeared in sentences such as “The agent called (the writer) from overseas to make an offer.” The intransitively biased verb “danced” appeared in sentences such as “The couple danced (the tango) every Friday night last summer.” Outcomes & Results: Both groups' reading times for critical segments were longer when the verb's transitivity bias did not match the sentence structure, particularly in intransitive sentences. Conclusions: The results were generally consistent with the Lexical Bias Hypothesis, and demonstrated that lexical biases affect on-line processing of syntactically simple sentences in people with aphasia and controls.

Editorial - Application of Medical Imaging Techniques to Studies of Human Language Processing and Acquisition

Editorial - Application of Medical Imaging Techniques to Studies of Human Language Processing and Acquisition

The effect of semantic relatedness on syntactic analysis: An fMRI study

The sentences we process in normal conversation tend to refer to information that we are familiar with rather than abstract, unrelated information. This allows for the use of knowledge stores to help facilitate comprehension processes. In many sentence comprehension studies, the stimuli are designed such that the use of world knowledge is limited. Here, we investigated how the semantic relatedness of sentence constituents influences sentence processing. A three factor design was employed in which processing phase (sentence vs. probe), syntactic complexity (object-relative vs. conjoined active) and the semantic relatedness of the nouns within the sentence was examined. We found a differential effect in two sub-regions of the left inferior frontal gyrus (LIFG). BA 44 revealed an effect of syntactic complexity while inferior portions of the LIFG (BA 47) revealed an effect of relatedness as well as an interaction between complexity and relatedness during the probe phase. In addition, significant differences in activation were observed when comparing the sentence processing and probe phases with the sentence phase eliciting stronger semantic related activation while the probe phase elicited stronger working memory related activation.

Off‐line sentence processing: What is involved in answering a comprehension probe?

The aim of this study was to better characterize the influence of the comprehension probe on syntax-related activation patterns observed in fMRI studies of sentence comprehension. In this study, sentence comprehension was assessed by presenting a true/false statement after each sentence. To disassociate the sentence reading from the comprehension probe activation, a 6-s delay was placed between these processing phases. Two factors were manipulated, one affected the sentence and the other affected the probe. The sentences were manipulated by varying their syntactic complexity; conjoined-active and object-relative sentences were examined. The comprehension probes asked whether one of the first two mentioned nouns in the preceding sentence performed the action of one of the two verbs. The probes were manipulated by varying the distance (number of intervening words) between the noun and verb within the sentence; there were three probe types: short distance, long distance, and false statements. The results, which focused on the processing taking place during the probe, showed that the distance manipulation resulted in significant differences in both behavioral and brain activation measures. This was particularly true of BA 44, which revealed an interaction between complexity and distance such that the complexity effect was all but eliminated for the long-distance condition. Additionally, we replicated our previous finding of syntactic complexity effects during the probe phase. Finally, post hoc analysis revealed that participants used two distinct strategies during sentence reading; significant effects of strategy use on both behavioral and brain activation data were observed.

Neural network processing of natural language: II. Towards a unified model of corticostriatal function in learning sentence comprehension and non-linguistic sequencing

A central issue in cognitive neuroscience today concerns how distributed neural networks in the brain that are used in language learning and processing can be involved in non-linguistic cognitive sequence learning. This issue is informed by a wealth of functional neurophysiology studies of sentence comprehension, along with a number of recent studies that examined the brain processes involved in learning non-linguistic sequences, or artificial grammar learning (AGL). The current research attempts to reconcile these data with several current neurophysiologically based models of sentence processing, through the specification of a neural network model whose architecture is constrained by the known cortico-striato-thalamo-cortical (CSTC) neuroanatomy of the human language system. The challenge is to develop simulation models that take into account constraints both from neuranatomical connectivity, and from functional imaging data, and that can actually learn and perform the same kind of language and artificial syntax tasks. In our proposed model, structural cues encoded in a recurrent cortical network in BA47 activate a CSTC circuit to modulate the flow of lexical semantic information from BA45 to an integrated representation of meaning at the sentence level in BA44/6. During language acquisition, corticostriatal plasticity is employed to allow closed class structure to drive thematic role assignment. From the AGL perspective, repetitive internal structure in the AGL strings is encoded in BA47, and activates the CSTC circuit to predict the next element in the sequence. Simulation results from Caplan’s [Caplan, D., Baker, C., & Dehaut, F. (1985). Syntactic determinants of sentence comprehension in aphasia. Cognition, 21, 117–175] test of syntactic comprehension, and from Gomez and Schvaneveldts’ [Gomez, R. L., & Schvaneveldt, R. W. (1994). What is learned from artificial grammars?. Transfer tests of simple association. Journal of Experimental Psychology: Learning, Memory and Cognition, 20, 396–410] artificial grammar learning experiments are presented. These results are discussed in the context of a brain architecture for learning grammatical structure for multiple natural languages, and non-linguistic sequences.

Brain responses to filled gaps

An unresolved issue in the study of sentence comprehension is whether the process of gap-filling is mediated by the construction of empty categories (traces), or whether the parser relates fillers directly to the associated verb’s argument structure. We conducted an event-related potentials (ERP) study that used the violation paradigm to examine the time course and spatial distribution of brain responses to ungrammatically filled gaps. The results indicate that the earliest brain response to the violation is an early left anterior negativity (eLAN). This ERP indexes an early phase of pure syntactic structure building, temporally preceding ERPs that reflect semantic integration and argument structure satisfaction. The finding is interpreted as evidence that gap-filling is mediated by structurally predicted empty categories, rather than directly by argument structure operations.

The On-line Study of Sentence Comprehension: An Examination of Dual Task Paradigms

This paper presents three studies which examine the susceptibility of sentence comprehension to intrusion by extra-sentential probe words in two on-line dual-task techniques commonly used to study sentence processing: the cross-modal lexical priming paradigm and the unimodal all-visual lexical priming paradigm. It provides both a general review and a direct empirical examination of the effects of task-demand in the on-line study of sentence comprehension. In all three studies, sentential materials were presented to participants together with a target probe word which constituted either a better or a worse continuation of the sentence at a point at which it was presented. Materials were identical for all three studies. The manner of presentation of the sentence materials was, however, manipulated; presentation was either visual, auditory (normal rate) or auditory (slow rate). The results demonstrate that a technique in which a visual target probe interrupts ongoing sentence processing (such as occurs in unimodal visual presentation and in very slow auditory sentence presentation) encourages the integration of the probe word into the on-going sentence. Thus, when using such 'sentence interrupting' techniques, additional care to equate probes is necessary. Importantly, however, the results provide strong evidence that the standard use of fluent cross-modality sentence investigation methods are immune from such external probe word intrusions into ongoing sentence processing and are thus accurately reflect underlying comprehension processes.

Intonational phrasing and constituency in language production and comprehension*

Abstract. In this paper, we investigate the relationship between intonational phrase boundaries and syntax in production and comprehension. Watson & Gibson (2004a) proposed that the likelihood of an intonational boundary at a word boundary is a function of 1) the size of the most recently completed constituent and 2) the size of the upcoming constituent if it is not an argument of the most recent head. We explore an alternate hypothesis to (1): the distance of integration between an upcoming word and its attachment site in the sentence influences the likelihood of an intonational boundary. In a production experiment (Experiment 1), we found that speakers’ intonational phrasing patterns were consistent with Watson & Gibson's original hypothesis. We then present two studies of sentence comprehension using converging paradigms which test the hypothesis that listeners exploit the relationship between syntax and the production‐based intonational boundaries by using a special parsing heuristic. In particular, we propose that listeners prefer not to attach incoming words to lexical heads that are followed by an intonational boundary. This hypothesis is validated in both Experiments 2 and 3.

An event-related brain potential study of sentence comprehension in preschoolers: semantic and morphosyntactic processing

The goal of this study was to investigate the distinctiveness and the relative time course of the event-related brain potentials (ERP) elicited by syntactically and semantically anomalous words within sentences in 36- and 48-month-old children. ERPs were recorded while children listened to semantically anomalous (i.e., My uncle will blow the movie*), syntactically anomalous (i.e., My uncle will watching the movie*) and control sentences (i.e., My uncle will watch the movie). Semantic violations elicited a negative slow wave with different peaks at 400, 600 and 800 ms in both age groups, whereas the morphosyntactic violations elicited two positive shifts: the first starting at 200 ms with a frontal distribution over the scalp and the second starting at 600 ms and peaking around 800 ms with a broad distribution across the scalp in 36-month-olds and anteriorly distributed for 48-month-olds. These results show that preschoolers display different ERP patterns to syntactic and to semantic violations within sentences. It is possible that the ERP effects here reported are analogous to those elicited in adults by the same type of stimuli, although differences in topography are evident.

ERP effects of the processing of syntactic long-distance dependencies

In behavioral studies on sentence comprehension, much evidence indicates that shorter dependencies are preferred over longer dependencies, and that longer dependencies incur a greater processing cost. However, it remains uncertain which of the various steps involved in the processing of long-distance dependencies is responsible for the increased cost of longer dependencies. Previous sentence comprehension studies using event-related potentials (ERPs) have revealed response components that reflect the construction [J. King, M. Kutas, Who did what and when? Using word- and clause-level ERPs to monitor working memory usage in reading. Journal of Cognitive Neuroscience, 7, (1995) 376–395.] and completion [E. Kaan, A. Harris, E. Gibson, P. Holcomb, The P600 as an index of syntactic integration difficulty. Language and Cognitive Processes, 5, (2000) 159–201.] of long-distance wh-dependencies. This article reports one off-line rating study and one ERP study that manipulated both the presence of wh-dependencies and the length of the dependencies (one clause vs. two clauses), with the aim of clarifying the locus of length-sensitivity and the functional role of associated ERP components. Results of the off-line study confirm that longer wh-dependencies incur greater processing cost. Results of the ERP study indicate that both a sustained anterior negativity that follows the initiation of the wh-dependency and also a late posterior positivity (P600) that marks the completion of the dependency are sensitive to the presence of a wh-dependency, but do not show amplitude variations reflecting the length of the dependency. However, the P600 is delayed when it marks the completion of a longer wh-dependency. This suggests that both the sustained negativity and the P600 reflect length-insensitive aspects of the construction of syntactic dependencies. In addition, an N400 component is elicited in the middle of the two clause wh-dependency, upon encountering a verb with an argument structure that prevents completion of the dependency.

Task-demand modulation of activation in Broca’s area

A number of brain imaging studies of sentence comprehension have reported evidence of activation in Broca’s area correlated with the processing of syntactically complex sentential material in both FMRI and PET studies (e.g., Caplan, 1995). This finding fits well with several decades of evidence concerning the effects of lesions on Broca’s area. Independent FMRI and PET investigations of working verbal memory (WVM) (e.g., Smith & Jonides, 1999) have also found evidence of activation of Broca’s area correlated with increased memory load. One hypothesis to consider based on these two pieces of evidence is that Broca’s area is involved in verbal working memory operations, and that complex structural processing employs this same resource. However, the experimental evidence does not easily reconcile with such a hypothesis. There is, for example, evidence suggesting that individuals with working memory deficits caused by brain lesions have no significant language processing difficulties, and, simultaneously, that individuals with language comprehension difficulties caused by lesion have no deficits in standard tests of WVM (e.g., Martin, 1990). In addition, studies of memory load in language have traditionally failed to find convincing demonstrations that the memory that is standardly examined in ‘working memory’ tests is the same memory employed in language processing (see, e.g., Caplan & Waters, 1999). One potential basis for the apparent inconsistency and conflict in this literature may lie in a little-considered aspect of these studies: the tasks (and their relevant ‘demands’) that have been employed in the study of both language and memory. Task demands have long been cited as prime candidates for non-reliability and non-replicability across both laboratories and techniques in neuro-imaging work (e.g., Ojemann et al, 1998). In the current fMRI study, we were interested in teasing apart the additional processing demands that standard sentence comprehension-tasks bring to the study of language processing from issues of sentence complexity per se. We undertook this study to attempt to resolve the potential conflict in the literature on the role of Broca’s area in cognitive and language processing.

Manifestations of aphasic symptoms in Hungarian

The characteristics of Hungarian aphasics reflect the difference in the features of Hungarian as a Finnish-Ugric language. These features are the highly complex use of inflectional morphemes, which are concatenated, providing markers for several functions in one word. Hungarian aphasics were systematically studied for features of agrammatism in language output, as well as in comprehension. The results of these studies suggest that in Hungarian there is a direct mapping of inflectional markings to semantics. The competition between definite and conditional conjugation is a major source of error just like in French, as well as competition between first and third persons. Omission errors occurred frequently, especially among Broca's aphasics omitting the indirect objects and Wernicke's aphasics the direct objects. Broca's aphasics also showed a lower level of pronoun use and article omission. Omissions and substitutions amounted to telegraphic speech in some patients, although this is not as marked as in English because of the high rate of omission in normal Hungarian. Wernicke's aphasics tended to produce paraphasic nouns and pronouns with some errors in inflection. Vowel harmony in the inflections was particularly resistant to deficit. Studies of sentence comprehension revealed that subject-verb agreement cues were most affected in Wernicke's aphasics and animacy cues were the weakest in Broca's aphasics. Although word order is rather free in Hungarian, canonical word orders were used for interpretation by all aphasics. Systematic studies of comprehension in Hungarian aphasics show that phonemic contrasts in words are more sensitive than sound discrimination tasks. Higher levels of sentence processing are influenced by the availability of case marking suffixes, which are numerous in Hungarian.

Determinants of sentence comprehension in aphasic patients in sentence-picture matching tasks.

The results of two studies of sentence comprehension in aphasic patients using sentence-picture matching tests are presented. In the first study, 52 aphasic patients were tested on 10 sentence types. Analysis of the number of correct responses per sentence type showed effects of syntactic complexity and number of propositions. Factor analysis yielded first factors that accounted for two-thirds of the variance in performance to which all sentence types contributed. Clustering analysis yielded groups of patients whose performances progressively deteriorated and in which performance was more affected by sentence types that were harder for the group overall. These results were very similar to those previously obtained using an enactment task. In the second study, 17 aphasic patients were tested on the same 10 sentence types using both sentence-picture matching and enactment tasks. Correlational analyses showed that performance on the two tests was significantly correlated across both subjects and sentences. The results provide data relevant to the determinants of the complexity of a sentence in auditory comprehension.

Grammatical theory and the study of sentence comprehension in aphasia: comments on Druks and Marshall (1995).

Druks and Marshall (1995) argue that aphasic comprehension problems are accountable as the consequence of a disrupted Case assignment module. But the analysis they present does not support their argument and it provides a distorted view of grammatically based analyses of brain-language relations.

Click monitoring revisited: an on-line study of sentence comprehension.

Spoken sentence comprehension is based upon rapid and complex psychological processes, yielding a constantly fluctuating cognitive load. The aim of this study was to evaluate on-line click monitoring, a classical but poorly exploited experimental method, which should allow for an easy measurement of processing load at any chosen point of experimental sentences. In Experiments 1 and 2, we obtained longer latencies to clicks located at the boundary of reversible object relative clauses than to clicks identically located in subject relatives and to clicks located earlier within object relatives. Experiment 3 further revealed that this effect of syntactic type was specific to transposed object relatives and did not occur with normal object relatives. In Experiment 4, we observed longer latencies with semantically reversible than with irreversible sentences, but no difference between actives and passives. These results were obtained under strict control of potential lexical and phonological biases, and suggest that on-line click monitoring may be one useful tool in the study of sentence comprehension.