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This introduction to the special issue entitled “Mechanisms of Variation in Reading Comprehension: Processes and Products” defines what is referred to as the process and product of reading comprehe...

The present research presents a novel method for investigating how characteristics of texts (words, sentences, and passages) and individuals (verbal and general cognitive skills) jointly influence eye-movement patterns over the time-course of reading, as well as comprehension accuracy. Fifty-one proficient readers read passages of varying complexity from the Gray Oral Reading Test, while their eye-movements were recorded. Participants also completed a large battery of tests assessing various components of reading comprehension ability (vocabulary size, decoding, phonological awareness, and experience with print), as well as general cognitive and executive skills. We used the Random Forests nonparametric regression technique to simultaneously estimate relative importance of all predictors. This method enabled us to trace the temporal engagement of individual predictors and entire predictor groups on eye-movements during reading, while avoiding the problems of model overfitting and collinearity, typical of parametric regression methods. Our findings both confirmed well-established results of prior research and pointed to a space of hypotheses that is as yet unexplored. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

The current study investigates the validity of the visual scanning hypothesis, which posits that rapid automatized naming (RAN) predicts reading skill partly because both require the ability to perform rapid sequential eye-movements. Our data consist of eye-movements collected while 124 young English speaking adults of variable reading skill read passages and performed six modifications of RAN. These modifications isolated articulatory, lexical, oculomotor and attentional task components of RAN. A further requirement for participants was to perform each of the RAN tasks in two directions—the habitual direction of reading (RAN forward) and from right to left and top to bottom (RAN backward). Participants who were better at oculomotor control in RAN-like tasks were better readers regardless of task type or direction. Our most crucial finding is that the explanatory contribution of oculomotor control in the RAN-reading relationship is independent of the practice effect afforded by the habitual direction of visual scanning in reading.

Semantic transparency effects during compound word recognition provide critical insight into the organization of semantic knowledge and the nature of semantic processing. The past 25 years of psycholinguistic research on compound semantic transparency has produced discrepant effects, leaving the existence and nature of its influence unresolved. In the present study, we examined the influence of semantic transparency and individual reading experience on eye-movement behavior during sentence reading. Eye-movement data were collected from 138 non-college-bound 16- to 26-year-old speakers of English in a sentence-reading task representing a total of 455 different compound words. Measures of individual differences in reading experience were collected from the same participants and consisted of standardized assessments of exposure to printed materials, vocabulary size, and word recognition skill. Statistical analyses revealed facilitatory effects of both Modifier-Compound and Head-Compound transparency throughout the eye-movement record. Moreover, the study reports interactions between Head-Compound transparency and measures of reading experience. Readers with a small amount exposure to printed materials and a limited vocabulary size exhibited slower processing in late eye-movement measures when reading highly transparent compounds relative to opaque compounds. The opposite effect was observed for readers with a relatively large amount of exposure to printed materials and a relatively larger vocabulary size, such that highly transparent compounds facilitated lexical processing. To account for the results, the authors posit a trade-off between 2 cognitive mechanisms, which is modulated by individual reading experience; that is, the benefit of semantic coactivation of closely related concepts, and the cost of discriminating between those concepts. (PsycINFO Database Record This work was supported by the Ontario Trillium Award and a Graduate fellowship awarded by the Lewis & Ruth Sherman Centre for Digital Scholarship (McMaster University) to Daniel Schmidtke. Julie A. Van Dyke’s contribution was supported by the following NIH grants to Haskins Laboratories: R01 HD-073288 (Julie A. Van Dyke, PI), and P01 HD-01994 (Jay G. Rueckl, PI). Victor Kuperman’s contribution was partially supported by the Canadian Social Sciences and Humanities Research Council Insight Development (430-2012-0488), and the Canadian Natural Sciences and Engineering Research Council (402395-2012), and the Early Researcher Award from the Ontario Research Fund. The authors are grateful to Morgan Bontrager for assistance with data collection and Kazunaga Matsuki for his contributions to statistical analyses. For technical support, we thank the Sherman Centre for Digital Scholarship at McMaster University. Thanks are also due to the attendees of the Twenty-First Annual Meeting of the Society for the Scientific Study of Reading, Santa Fe, New Mexico, where this work was presented in July 2014; the attendees of the Eighteenth Annual European Conference on Eye Movements, Vienna, Austria, where this work was presented in August 2015; attendees of the Third American International Morphology Meeting, which was held in Amherst, Massachusetts, in October 2015; and also to members of the Quantitative Linguistics research unit at the University of Tübingen, Tübingen, Germany, where this work was presented in April 2016. We also wish to thank Harald Baayen, Thomas Spalding and Christina Gagné for commenting upon earlier versions of this article. The content is solely the responsibility of the authors and does not necessarily represent the official views of the U.S. National Institutes of Health or the Canadian Government.

Studies investigating individual differences in reading ability often involve data sets containing a large number of collinear predictors and a small number of observations. In this paper, we discuss the method of Random Forests and demonstrate its suitability for addressing the statistical concerns raised by such datasets. The method is contrasted with other methods of estimating relative variable importance, especially Dominance Analysis and Multimodel Inference. All methods were applied to a dataset that gauged eye-movements during reading and offline comprehension in the context of multiple ability measures with high collinearity due to their shared verbal core. We demonstrate that the Random Forests method surpasses other methods in its ability to handle model overfitting, and accounts for a comparable or larger amount of variance in reading measures relative to other methods.

Gough and Tunmer’s (1986) simple view of reading (SVR) proposed that reading comprehension (RC) is a function of language comprehension (LC) and word recognition/decoding. Braze et al. (2007) presented data suggesting an extension of the SVR in which knowledge of vocabulary (V) affected RC over and above the effects of LC. Tunmer and Chapman (2012) found a similar independent contribution of V to RC when the data were analyzed by hierarchical regression. However, additional analysis by factor analysis and structural equation modeling indicated that the effect of V on RC was, in fact, completely captured by LC itself and there was no need to posit a separate direct effect of V on RC. In the present study, we present new data from young adults with sub-optimal reading skill (N = 286). Latent variable and regression analyses support Gough and Tunmer’s original proposal and the conclusions of Tunmer and Chapman that V can be considered a component of LC and not an independent contributor to RC.

Past studies have shown that antecedent prominence affects the processing of a pronoun, but these studies have used experimental methodologies that do not make it possible to determine at what stage(s) of pronominal resolution these effects occur. We used the speed-accuracy tradeoff procedure to investigate whether antecedent prominence affects the accuracy of antecedent retrieval, the speed of resolution, or both. Consistent with previous results, we find that accuracy is higher when antecedents are prominent than when they are not (cf. Foraker & McElree, 2007). However, in contrast to previous results, we also find that prominence impacts the speed with which the pronominal dependency is resolved. We consider the implications of our findings for various models of pronoun resolution and offer suggestions for how to implement prominence-sensitive speed differences within a cue-based retrieval architecture. © American Psychological Association, [2018]. This paper is not the copy of record and may not exactly replicate the authoritative document published in the APA journal. Please do not copy or cite without author's permission. The final article is available, upon publication, at: http://dx.doi.org/10.1037/xlm0000646

The link between phonological abilities, as indexed through measures of phonological awareness and phonological memory, and the development of skilled reading is well-established in both typical and atypical populations. However, the specific nature of the skill differences tapped by these meta-phonological tasks remains a debated topic. To the extent that such tasks are indicative of differences in phonological processing, individuals who perform poorly on them have been mostly assumed to have underspecified (or “fuzzy”) phonological representations (e.g., Tallal et al., 1998), which overlap excessively due to imprecise phonemic encoding. An alternative hypothesis holds that performance deficits on these tasks may derive from overspecified phonological representations, in which case speech sounds are perceived in allophonic (i.e., phonetically distinct variants of a single phonemic category) instead of typical phonemic units (Serniclaes, 2006). While both accounts predict mismatch between spoken sound categories and written symbols that may eventually lead to phonological-based reading difficulty, their implications are quite different with regard to the details of online phonological processing and speech perception at large. To examine these two hypotheses, we used a visual world eye tracking paradigm modeled after that of Dahan et al. (2001), to investigate individual differences in sensitivity to subphonemic information in young adults with a wide range of phonological skills and reading-related abilities (N = 60). Our findings suggest that subphonemic sensitivity is inversely correlated with meta-phonological task performance, consistent with the overspecification hypothesis. Our study of individual differences in subphonemic sensitivity during online speech processing contributes important new knowledge regarding the underlying nature of phonological skills and representations relevant to development of reading skill across a wide spectrum of abilities.

This exploratory study investigated relations between individual differences in cortical grey matter structure and young adult readers’ cognitive profiles. Whole-brain analyses revealed neuroanatomical correlations with word and nonword reading ability (decoding), and experience with printed matter. Decoding was positively correlated with grey matter volume (GMV) in left superior temporal sulcus, and thickness (GMT) in right superior temporal gyrus. Print exposure was negatively correlated with GMT in left inferior frontal gyrus (pars opercularis) and left fusiform gyrus (including the visual word form area). Both measures also correlated with supramarginal gyrus (SMG), but in spatially distinct subregions: decoding was positively associated with GMV in left anterior SMG, and print exposure was negatively associated with GMT in left posterior SMG. Our comprehensive approach to assessment both confirms and refines our understanding of the novel relation between the structure of pSMG and proficient reading, and unifies previous research relating cortical structure and reading skill. © 2018 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License (http://creativecommons.org/licenses/by-nc-nd/ 4.0/)

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link. Recent studies have found considerable individual variation in language comprehenders’ predictive behaviors, as revealed by their anticipatory eye movements during language comprehension. The current study investigated the relationship between these predictive behaviors and the language and literacy skills of a diverse, community-based sample of young adults. We found that rapid automatized naming (RAN) was a key determinant of comprehenders’ prediction ability (e.g., as reflected in predictive eye movements to a WHITE CAKE on hearing “The boy will eat the white…”). Simultaneously, comprehension-based measures predicted participants’ ability to inhibit eye movements to objects that shared features with predictable referents but were implausible completions (e.g., as reflected in eye movements to a white but inedible WHITE CAR). These findings suggest that the excitatory and inhibitory mechanisms that support prediction during language processing are closely linked with specific cognitive abilities that support literacy. We show that a self-organizing cognitive architecture captures this pattern of results.

Researchers have established a relationship between beginning readers’ silent comprehension ability and their prosodic fluency, such that readers who read aloud with appropriate prosody tend to have higher scores on silent reading comprehension assessments. The current study was designed to investigate this relationship in two groups of high school readers: Specifically Poor Comprehenders (SPCs), who have adequate word level and phonological skills but poor reading comprehension ability, and a group of age- and decoding skill-matched controls. We compared the prosodic fluency of the two groups by determining how effectively they produced prosodic cues to syntactic and semantic structure in imitations of a model speaker’s production of syntactically and semantically varied sentences. Analyses of pitch and duration patterns revealed that speakers in both groups produced the expected prosodic patterns; however, controls provided stronger durational cues to syntactic structure. These results demonstrate that the relationship between prosodic fluency and reading comprehension continues past the stage of early reading instruction. Moreover, they suggest that prosodically fluent speakers may also generate more fluent implicit prosodic representations during silent reading, leading to more effective comprehension.

The cue-based retrieval theory (Lewis, Vasishth, & Van Dyke, 2006) predicts that interference from similar distractors should create difficulty for argument integration, however this hypothesis has only been examined in the written modality. The current study uses the Visual World Paradigm (VWP) to assess its feasibility to study retrieval interference arising from distractors present in a visual display during spoken language comprehension. The study aims to extend findings from Van Dyke & McElree (2006), which utilized a dual-task paradigm with written sentences in which they manipulated the relationship between extra-sentential distractors and the semantic retrieval cues from a verb, to the spoken modality. Results indicate that retrieval interference effects do occur in the spoken modality, manifesting immediately upon encountering the verbal retrieval cue for inaccurate trials when the distractors are present in the visual field. We also observed indicators of repair processes in trials containing semantic distractors, which were ultimately answered correctly. We conclude that the VWP is a useful tool for investigating retrieval interference effects, including both the online effects of distractors and their after-effects, when repair is initiated. This work paves the way for further studies of retrieval interference in the spoken modality, which is especially significant for examining the phenomenon in pre-reading children, non-reading adults (e.g., people with aphasia), and spoken language bilinguals.

This study investigated phonological components of reading skill at two ages, using a novel pseudoword repetition task for assessing phonological memory (PM). Pseudowords were designed to incorporate control over segmental, prosodic and lexical features. In experiment 1, the materials were administered to 3- and 4-year-old children together with a standardized test of phonological awareness (PA). PA and pseudoword repetition showed a moderate positive correlation, independent of age. Experiment 2, which targeted young adults, employed the same pseudoword materials, with a different administration protocol, together with standardized indices of PA, other memory measures, and decoding skill. The results showed moderate to strong positive correlations among our novel pseudoword repetition task, measures of PM and PA, and decoding. Together, the findings demonstrate the feasibility of assessing PM with the same carefully controlled materials at widely spaced points in age, adding to present resources for assessing phonological memory and better enabling future studies to map the development of relationships among phonological capabilities in both typically developing children and those with language-related impairments.

The parameters of the human memory system constrain the operation of language comprehension processes. In the memory literature, both decay and interference have been proposed as causes of forgetting; however, while there is a long history of research establishing the nature of interference effects in memory, the effects of decay are much more poorly supported. Nevertheless, research investigating the limitations of the human sentence processing mechanism typically focus on decay-based explanations, emphasizing the role of capacity, while the role of interference has received comparatively little attention. This paper reviews both accounts of difficulty in language comprehension by drawing direct connections to research in the memory domain. Capacity-based accounts are found to be untenable, diverging substantially from what is known about the operation of the human memory system. In contrast, recent research investigating comprehension difficulty using a retrieval-interference paradigm is shown to be wholly consistent with both behavioral and neuropsychological memory phenomena. The implications of adopting a retrieval-interference approach to investigating individual variation in language comprehension are discussed.

The role of interference as a primary determinant of forgetting in memory has long been accepted, however its role as a contributor to poor comprehension is just beginning to be understood. The current paper reports two studies, in which speed-accuracy tradeoff and eye-tracking methodologies were used with the same materials to provide converging evidence for the role of syntactic and semantic cues as mediators of both proactive (PI) and retroactive interference (RI) during comprehension. Consistent with previous work (e.g., Van Dyke & Lewis, 2003), we found that syntactic constraints at the retrieval site are among the cues that drive retrieval in comprehension, and that these constraints effectively limit interference from potential distractors with semantic/pragmatic properties in common with the target constituent. The data are discussed in terms of a cue-overload account, in which interference both arises from and is mediated through a direct-access retrieval mechanism that utilizes a linear, weighted cue-combinatoric scheme.

BACKGROUND: There is still a dearth of information about grammatical aspects of language production in aphasia. AIMS: Making novel use of methods of elicited production aimed at testing the limits of competence, we studied three cases of chronic aphasia, stemming from major stroke. We asked: (1) Whether the elicited production method reveals sparing of language abilities not readily evidenced in spontaneous utterances or on conventional aphasia tests. (2) Which language production abilities survive damage to both Broca's region and Wernicke's region? MATERIALSPROCEDURES: Targeted words, morphological and syntactic structures were elicited by sentence completion with supporting linguistic and visual context. Targets were never modelled during the procedure. For verbs, visual and auditory contexts emphasise completed actions, targeting past tense forms. Lesion description was based on structural MRI scans. OUTCOMESRESULTS: The three participants showed partially spared ability to produce nouns, adjectives, and verb stems in context. The elicitation method proved more productive in some cases than picture prompts or sentence prompts. Past tense inflections were usually omitted. Hence stems and inflections were dissociable. Two participants showed partial success with the passive, and no participant produced a full relative clause, including the relative pronoun, but two produced reduced forms of subject relatives. Partial sparing of production capability in these cases points to the likely importance of portions of the left hemisphere remote from Broca and Wernicke regions. CONCLUSIONS: This application of elicited production methodology demonstrates possibilities of lexical, morphological, and syntactic production not evident in spontaneous utterances or by conventional aphasia tests. Some lexical and grammatical capabilities survived massive damage to both anterior and posterior portions of the left hemisphere.

A substantial body of evidence points to a cue-based direct-access retrieval mechanism as a crucial component of skilled adult reading. We report two experiments aimed at examining whether poor readers are able to make use of the same retrieval mechanism. This is significant in light of findings that poor readers have difficulty retrieving linguistic information (e.g., Perfetti, 1985). Our experiments are based on a previous demonstration of direct-access retrieval in language processing, presented in McElree, Foraker, & Dyer (2003). Experiment 1 replicates the original result using an auditory implementation of the Speed-Accuracy Tradeoff method. This finding represents a significant methodological advance, as it opens up the possibility of exploring retrieval speeds in non-reading populations. Experiment 2 provides evidence that poor readers do use a direct-access retrieval mechanism during listening comprehension, despite overall poorer accuracy and slower retrieval speeds relative to skilled readers. The findings are discussed with respect to hypotheses about the source of poor reading comprehension.

Phonological properties of the words in a sentence have been shown to affect processing fluency and comprehension. However, the exact role of phonology in sentence comprehension remains unclear. If constituents are stored in working memory during routine processing and accessed through their phonological code, phonological information may exert a pervasive influence on post-lexical comprehension processes such as retrieval for thematic integration. On the other hand, if access to constituents in memory during parsing is guided primarily by syntactic and semantic information, the parser should be isolated from phonologically based effects. In two self-paced reading experiments, we tested whether phonological overlap between distractors and a retrieval target caused retrieval interference during thematic integration. We found that phonological overlap creates difficulty during the initial encoding of the filler, but there was no evidence that phonological overlap caused later interference when the filler was retrieved for thematic integration. Despite effects at encoding, phonological interference did not have a detrimental effect on comprehension. These results suggest that phonological information is not used as a retrieval cue during routine dependency construction in incremental sentence processing. We conclude by considering the potential importance of phonology in parsing under conditions of extraordinary syntactic and/or semantic interference.

This paper presents the cue-based retrieval theory of parsing and reanalysis and illustrates how this account can accommodate a number of key results about parsing and reanalysis, including effects due to structure, distance, and type of structural change. Three offline experiments and one online experiment permit establishing the locus of these effects as due to properties of the initial parsing processes or to the repair mechanism. Specifically, the data reported here suggest that a structural factor specific to the operation of the parser, retrieval interference, affects attachment uniformly across ambiguous and unambiguous sentences and serves to create a limit on successful repair. In addition, these experiments suggest that distance of the head of an ambiguous phrase from its disambiguator affects repair processes—and not attachment processes—independently of the interference effect. These results are interpreted with respect to alternative models of reanalysis, which are contrasted with the cue-based retrieval account, which requires no distinct repair mechanism to account for the current results. A further contribution of this article is to suggest a statistical correction for individual variance in reading rates. Statistical analyses on individual subject data confirmed previous speculations regarding a possible increase in reading rates as subjects move through a sentence. While this individual variation limits fair comparisons of reading times in sentence regions that appear in non-identical serial positions, we demonstrate that such comparisons become meaningful when the appropriate regression analyses have been performed.

Accounts of comprehension failure, whether in the case of readers with poor skill or when syntactic complexity is high, have overwhelmingly implicated working memory capacity as the key causal factor. However, extant research suggests that this position is not well supported by evidence on the span of active memory during online sentence processing, nor is it well motivated by models that make explicit claims about the memory mechanisms that support language processing. The current study suggests that sensitivity to interference from similar items in memory may provide a better explanation of comprehension failure. Through administration of a comprehensive skill battery, we found that the previously observed association of working memory with comprehension is likely due to the collinearity of working memory with many other reading-related skills, especially IQ. In analyses which removed variance shared with IQ, we found that receptive vocabulary knowledge was the only significant predictor of comprehension performance in our task out of a battery of 24 skill measures. In addition, receptive vocabulary and non-verbal memory for serial order—but not simple verbal memory or working memory—were the only predictors of reading times in the region where interference had its primary affect. We interpret these results in light of a model that emphasizes retrieval interference and the quality of lexical representations as key determinants of successful comprehension.

Management of patients with aph asia often focuses on training nonverbal augmentative communication strategies; however, these strategies frequently do not generalize to natural situations. The limited success may be because training waS not sufficient to produce an integrated multimodal semantic representation. The purpose of this study was to examine whether simultaneous training of stimuli in both verbal and nonverbal modalities would solidify the links within the semantic network and improve switching among modalities as needed in conversation. Two individuals with severe aphasia participated in 6 to 8 hours of Multi moda I Communication Training (MeT), during which they conveyed a concept by verbalizing, gesturing, writing, and drawing. After practice with all modalities for a single concept, a new concept was introduced. Results showed that one participant increased conveyance of concepts on the functional communication task using a variety of modalities. Although some improvement was seen with the second participant, his overall performance remained poor, likely because of a greater impairment in semantic knowledge. After a brief period of semantic training, the second participant demonstrated additional gains. Thus, MeT may serve to increase switching among verbal and nonverbal modalities in individuals with intact semantic representations, thereby increasing the likelihood that individuals will use an alternative method to communicate.

We review major issues in research on reading, including theories of word reading, cross-writing system comparisons, comprehension, reading difficulties, learning how to read, and cognitive neuroscience studies of reading. Each of these topics has psycholinguistic components that reflect the language foundations of reading. These foundations lie in two facts: (1) a writing system connects to a linguistic system at one or more levels, meaning that word reading is partially a psycholinguistic process; and (2): reading comprehension shares processes (e.g., parsing) with general language comprehension. One trend of recent research is the development of models of word identification that rely on single rather than dual mechanisms and their extension to explain reading difficulties. Another is the conclusion that phonology plays a role in reading that cuts across writing systems. Reading comprehension research continues to reflect two different traditions, sentence parsing and text comprehension. Both show increasing influence of general cognitive explanations, as opposed to strictly linguistic explanations, for comprehension phenomena. Studies of brain activation bring converging evidence on reading processes and provide neuroanatomical correlates of reading problems. In one area, the acquisition and teaching of reading, advances come from increasing consolidation and practical use of previous research gains.

According to the cue-based parsing approach (Lewis, Vasishth, & Van Dyke, 2006), sentence comprehension difficulty derives from interference from material that partially matches syntactic and semantic retrieval cues. In a 2 (low vs. high semantic interference) 2 (low vs. high syntactic interference) fMRI study, greater activation was observed in left BA44/45 for high versus low syntactic interference conditions following sentences and in left BA45/47 for high versus low semantic interference conditions following comprehension questions. A conjunction analysis showed BA45 associated with both types of interference, while BA47 was associated with only semantic interference. Greater activation was also observed in the left STG in the high interference conditions. Importantly, the results for the LIFG could not be attributed to greater working memory capacity demands for high interference conditions. The results favor a fractionation of the LIFG wherein BA45 is associated with post-retrieval selection and BA47 with controlled retrieval of semantic information.

The importance of vocabulary in reading comprehension emphasizes the need to accurately assess an individual's familiarity with words. The present article highlights problems with using occurrence counts in corpora as an index of word familiarity, especially when studying individuals varying in reading experience. We demonstrate via computational simulations and norming studies that corpus-based word frequencies systematically overestimate strengths of word representations, especially in the low-frequency range and in smaller-size vocabularies. Experience-driven differences in word familiarity prove to be faithfully captured by the subjective frequency ratings collected from responders at different experience levels. When matched on those levels, this lexical measure explains more variance than corpus-based frequencies in eye-movement and lexical decision latencies to English words, attested in populations with varied reading experience and skill. Furthermore, the use of subjective frequencies removes the widely reported (corpus) Frequency × Skill interaction, showing that more skilled readers are equally faster in processing any word than the less skilled readers, not disproportionally faster in processing lower frequency words. This finding challenges the view that the more skilled an individual is in generic mechanisms of word processing, the less reliant he or she will be on the actual lexical characteristics of that word.

This study is a large-scale exploration of the influence that individual reading skills exert on eye-movement behavior in sentence reading. Seventy-one non-college-bound 16– 24 year-old speakers of English completed a battery of 18 verbal and cognitive skill assessments, and read a series of sentences as their eye-movements were monitored. Statistical analyses were performed to establish what tests of reading abilities were predictive of eye movement patterns across this population and how strong the effects were. We found that individual scores in rapid automatized naming and word identification tests (i) were the only participant variables with reliable predictivity throughout the time-course of reading; (ii) elicited effects that superceded in magnitude the effects of established predictors like word length or frequency; and (iii) strongly modulated the influence of word length and frequency on fixation times. We discuss implications of our findings for testing reading ability, as well as for research of eye-movements in reading.

We present new evidence based on fMRI for the existence and neural architecture of an abstract supramodal language system that can integrate linguistic inputs arising from different modalities such that speech and print each activate a common code. Working with sentence material, our aim was to find out where the putative supramodal system is located and how it responds to comprehension challenges. To probe these questions we examined BOLD activity in experienced readers while they performed a semantic categorization task with matched written or spoken sentences that were either well-formed or contained anomalies of syntactic form or pragmatic content. On whole-brain scans, both anomalies increased net activity over non-anomalous baseline sentences, chiefly at left frontal and temporal regions of heteromodal cortex. The anomaly-sensitive sites correspond approximately to those that previous studies (Michael et al., 2001; Constable et al., 2004) have found to be sensitive to other differences in sentence complexity (object relative minus subject relative). Regions of interest (ROIs) were defined by peak response to anomaly averaging over modality conditions. Each anomaly-sensitive ROI showed the same pattern of response across sentence types in each modality. Voxel-by-voxel exploration over the whole brain based on a cosine similarity measure of common function confirmed the specificity of supramodal zones.

Evidence from 3 experiments reveals interference effects from structural relationships that are inconsistent with any grammatical parse of the perceived input. Processing disruption was observed when items occurring between a head and a dependent overlapped with either (or both) syntactic or semantic features of the dependent. Effects of syntactic interference occur in the earliest online measures in the region where the retrieval of a long-distance dependent occurs. Semantic interference effects occur in later online measures at the end of the sentence. Both effects endure in offline comprehension measures, suggesting that interfering items participate in incorrect interpretations that resist reanalysis. The data are discussed in terms of a cue-based retrieval account of parsing, which reconciles the fact that the parser must violate the grammar in order for these interference effects to occur. Broader implications of this research indicate a need for a precise specification of the interface between the parsing mechanism and the memory system that supports language comprehension.

Understanding a sentence requires a working memory of the partial products of comprehension, so that linguistic relations between temporally distal parts of the sentence can be rapidly computed. We describe an emerging theoretical framework for this working memory system that incorporates several independently motivated principles of memory: a sharply limited attentional focus, rapid retrieval of item (but not order) information subject to interference from similar items, and activation decay (forgetting over time). A computational model embodying these principles provides an explanation of the functional capacities and severe limitations of human processing, as well as accounts of reading times. The broad implication is that the detailed nature of cross-linguistic sentence processing emerges from the interaction of general principles of human memory with the specialized task of language comprehension.

The role of interference effects in sentence processing has recently begun to receive attention, however whether these effects arise during encoding or retrieval remains unclear. This paper draws on basic memory research to help distinguish these explanations and reports data from an experiment that manipulates the possibility for retrieval interference while holding encoding conditions constant. We found clear support for the principle of cue-overload, wherein cues available at retrieval cannot uniquely distinguish among competitors, thus giving rise to interference effects. We discuss the data in relation to a cue-based parsing framework (Van Dyke & Lewis, 2003) and other interference effects observed in sentence processing (e.g., Gordon, Hendrick, & Johnson, 2001, 2004). We conclude from the available data that the memory system that subserves language comprehension operates according to similar principles as memory in other domains.

On page 165, left column, second paragraph, lines 20–27 should read: ‘‘Hence, the Gordon et al. (2001, 2004) findings can be explained with a simple assumption that the match of the target to a pronoun or to a proper name is lower than that to a common noun phrase, perhaps because the referential properties associated with the former make it more distinctive than those associated with the later.’’ www.elsevier.com/locate/jml