Developmental differences in children's context-dependent word learning

In this study, 2.5-, 3-, and 4-year-olds (N = 108) participated in a novel noun generalization task in which background context was manipulated. During the learning phase of each trial, children were presented with exemplars in one or multiple background contexts. At the test, children were asked to generalize to a novel exemplar in either the same or a different context. The 2.5-year-olds’ performance was supported by matching contexts; otherwise, children in this age group demonstrated context dependent generalization. The 3-year-olds’ performance was also supported by matching contexts; however, children in this age group were aided by training in multiple contexts as well. Finally, the 4-year-olds demonstrated high performance in all conditions. The results are discussed in terms of the relationship between word learning and memory processes; both general memory development and memory developments specific to word learning (e.g., retention of linguistic labels) are likely to support word learning and generalization.     

Ability to stand alone and processing of open-class and closed-class words: Isolation versus context

Four experiments investigating processing of closed-class and open-class words in isolation and in sentence contexts are reported. Taft (1990) reported that closed-class words which could not meaningfully stand alone and open-class words which could not meaningfully stand alone incurred longer lexical decision responses than did control words. Taft also reported that closed-class and open-class words which could stand alone meaningfully were not associated with longer lexical decision responses than were control words. Experiments 1 and 2 replicated Taft 's effect of ability to stand alone on lexical decision responses to closed-class and open-class words presented in isolation. In Experiments 3 and 4, the same lexical decision targets were presented as part of semantically neutral context sentences in a moving window paradigm. The stand-alone effect was not present in Experiments 3 and 4. The results suggest Toft's conclusion that meaningfulness of a word influences lexical decision needs revision. An explanation is provided according to which support from message level and syntactic and lexical sources in sentence contexts influence words' perceived “meaningfulness.”     

WORKING MEMORY CAPACITY DISSOCIATES LEXICAL AND SENTENTIAL CONTEXT EFFECTS

Abstract— Semantically associated and unassociated word pairs were embedded in normal meaningful sentences and in sentences that were semantically anomalous throughout The influence of lexical context was isolated via comparison of responses to the second words of the associated and unassociated pairs. The influence of sentence-level context was isolated by comparing responses to the same words in the two sentence types Subjects of high, medium and low working memory capacity (as evaluated by the reading span test) showed modulations of event-related brain potentials in response so lexical context. In contrast, only the high- and medium-capacity groups were responsive to purely sentence-level semantic context. The results demonstrate that sentential context influences the processing of words in intermediate sentence positions at normal reading speeds but that the on-line utilization of this context is more demanding of working memory than single-word contexts.     

Is there a natural order for expressing semantic relations?

All languages rely to some extent on word order to signal relational information. Why? We address this question by exploring communicative and cognitive factors that could lead to a reliance on word order. In Study 1, adults were asked to describe scenes to another using their hands and not their mouths. The question was whether this home-made "language" would contain gesture sentences with consistent order. In addition, we asked whether reliance on order would be influenced by three communicative factors (whether the communication partner is permitted to give feedback; whether the information to be communicated is present in the context that recipient and gesturer share; whether the gesturer assumes the role of gesture receiver as well as gesture producer). We found that, not only was consistent ordering of semantic elements robust across the range of communication situations, but the same non-English order appeared in all contexts. Study 2 explored whether this non-English order is found only when a person attempts to share information with another. Adults were asked to reconstruct scenes in a non-communicative context using pictures drawn on transparencies. The adults picked up the pictures for their reconstructions in a consistent order, and that order was the same non-English order found in Study 1. Finding consistent ordering patterns in a non-communicative context suggests that word order is not driven solely by the demands of communicating information to another, but may reflect a more general property of human thought.     

Electrophysiological evidence for the time-course of verifying text ideas

We examined how verb factivity influences the ability of readers to detect and resolve the mismatch of receiving false referents in relation to true referents in discourse contexts. Factive verbs (e.g., know), but not nonfactive verbs (believe), entail the truth of their complements. Recent research by Singer [Singer, M. (2006). Verification of text ideas during reading. Journal of Memory and Language, 54, 574-591] suggests that there are pragmatic costs associated with knowing something that is clearly false and only believing something that is clearly true. However, because Singer measured reading times for full sentences, it could not be determined whether these costs were initiated upon the appearance of the critical target word (i.e., the word that validated or invalidated previous text ideas) or at a later point in the sentences. In the present research we recorded event-related brain potentials while people read the same passages for comprehension and analyzed potentials evoked to the critical target words. Our results demonstrate that the brain distinguishes between true and false target words by at least 200ms after their onset, and that the pragmatic costs identified by Singer lead to interactions between verb factivity and truth in both early (P2) and later occurring brain components (late phase of N400 and late frontal positivity). In general, the results suggest readers had greater difficulty integrating false nouns than true nouns following factive than nonfactive verbs, and that detection of this mismatch also occurred earlier following factive verbs. Our results provide insight into the time-course of the processes that underlie the verification of text ideas, and extend neurocognitive research on anaphoric resolution.     

Predicting language: MEG evidence for lexical preactivation

It is widely assumed that prediction plays a substantial role in language processing. However, despite numerous studies demonstrating that contextual information facilitates both syntactic and lexical–semantic processing, there exists no direct evidence pertaining to the neural correlates of the prediction process itself. Using magnetoencephalography (MEG), this study found that brain activity was modulated by whether or not a specific noun could be predicted, given a picture prime. Specifically, before the noun was presented, predictive contexts triggered enhanced activation in left mid-temporal cortex (implicated in lexical access), ventro-medial prefrontal cortex (previously associated with top-down processing), and visual cortex (hypothesized to index the preactivation of predicted form features), successively. This finding suggests that predictive language processing recruits a top-down network where predicted words are activated at different levels of representation, from more ‘abstract’ lexical–semantic representations in temporal cortex, all the way down to visual word form features. The same brain regions that exhibited enhanced activation for predictive contexts before the onset of the noun showed effects of congruence during the target word. To our knowledge, this study is one of the first to directly investigate the anticipatory stage of predictive language processing.     

Understanding words in sentence contexts: the time course of ambiguity resolution

Spoken language comprehension requires rapid integration of information from multiple linguistic sources. In the present study we addressed the temporal aspects of this integration process by focusing on the time course of the selection of the appropriate meaning of lexical ambiguities ("bank") in sentence contexts. Successful selection of the contextually appropriate meaning of the ambiguous word is dependent upon the rapid binding of the contextual information in the sentence to the appropriate meaning of the ambiguity. We used the N400 to identify the time course of this binding process. The N400 was measured to target words that followed three types of context sentences. In the concordant context, the sentence biased the meaning of the sentence-final ambiguous word so that it was related to the target. In the discordant context, the sentence context biased the meaning so that it was not related to the target. In the unrelated control condition, the sentences ended in an unambiguous noun that was unrelated to the target. Half of the concordant sentences biased the dominant meaning, and the other half biased the subordinate meaning of the sentence-final ambiguous words. The ISI between onset of the target word and offset of the sentence-final word of the context sentence was 100 ms in one version of the experiment, and 1250 ms in the second version. We found that (i) the lexically dominant meaning is always partly activated, independent of context, (ii) initially both dominant and subordinate meaning are (partly) activated, which suggests that contextual and lexical factors both contribute to sentence interpretation without context completely overriding lexical information, and (iii) strong lexical influences remain present for a relatively long period of time.     

On the young child's use of lexis and syntax in understanding locative instructions

The ability of two and three year old children to comprehend in, on and under was tested in five contexts. In the first context, where responses did not depend on the child manipulating the experimental objects, responses were invariably correct except for some difficulty with under in the youngest subjects. In the other four contexts, which did involve manipulation of the objects by the child, responses varied as a function of the noun phrases used to refer to the experimental objects which themselves remained the same across different contexts. The result suggest that the young child's comprehension of instructions involves an interaction between aspects of the instruction's lexis and syntax and the child's construal of context.     

Brain potentials during language production in children and adults: An ERP study of the English past tense

The current study examines the neural correlates of 8-to-12-year-old children and adults producing inflected word forms, specifically regular vs. irregular past-tense forms in English, using a silent production paradigm. ERPs were time-locked to a visual cue for silent production of either a regular or irregular past-tense form or a 3rd person singular present tense form of a given verb (e.g., walked/sang vs. walks/sings). Subsequently, another visual stimulus cued participants for an overt vocalization of their response. ERP results for the adult group revealed a negativity 300–450 ms after the silent-production cue for regular compared to irregular past-tense forms. There was no difference in the present form condition. Children’s brain potentials revealed developmental changes, with the older children demonstrating more adult-like ERP responses than the younger ones. We interpret the observed ERP responses as reflecting combinatorial processing involved in regular (but not irregular) past-tense formation.     

Activating event knowledge

An increasing number of results in sentence and discourse processing demonstrate that comprehension relies on rich pragmatic knowledge about real-world events, and that incoming words incrementally activate such knowledge. If so, then even outside of any larger context, nouns should activate knowledge of the generalized events that they denote or typically play a role in. We used short stimulus onset asynchrony priming to demonstrate that (1) event nouns prime people (sale-shopper) and objects (trip-luggage) commonly found at those events; (2) location nouns prime people/animals (hospital-doctor) and objects (barn-hay) commonly found at those locations; and (3) instrument nouns prime things on which those instruments are commonly used (key-door), but not the types of people who tend to use them (hose-gardener). The priming effects are not due to normative word association. On our account, facilitation results from event knowledge relating primes and targets. This has much in common with computational models like LSA or BEAGLE in which one word primes another if they frequently occur in similar contexts. LSA predicts priming for all six experiments, whereas BEAGLE correctly predicted that priming should not occur for the instrument-people relation but should occur for the other five. We conclude that event-based relations are encoded in semantic memory and computed as part of word meaning, and have a strong influence on language comprehension.     

The Interaction of Contextual and Syntactic Information in the Processing of Turkish Anaphors

In contrast with languages where anaphors can be classified into pronouns and reflexives, Turkish has a tripartite system that consists of the anaphors o, kendi, and kendisi. The syntactic literature on these anaphors has proposed that whereas o behaves like a pronoun and kendi behaves like a reflexive, kendisi has a more flexible behavior and it can function as both a pronoun and a reflexive. Using acceptability judgments and a self-paced reading task, we examined how Turkish anaphors are processed in isolated sentences and within larger discourse contexts. We manipulated contextual information by creating passages where the context favored a local, long-distance or extra-sentential referent prior to the appearance of the anaphor. We measured the effect of the context on participants’ reading times and their end-of-trial coreference assignments. Our results suggest that contextual information affects the interpretive possibilities associated with an anaphor, but that the influence of context depends on the degree to which the anaphor is syntactically constrained.     

维吾尔族与汉族的大学生在汉语歧义词消解中的语境促进效应及反应抑制效应

词汇歧义是语言的普遍现象。在汉语中, 歧义词的种类繁多, 是少数民族学生汉语学习困难的重要原因之一。通过两个实验, 考察在不同加工时间条件下维吾尔族和汉族的大学生在汉语歧义词消解中的语境促进效应及抑制效应。结果发现, 两个民族的大学生均出现了语境促进效应, 但在短时加工条件下, 汉族大学生的语境促进效应显著大于维吾尔族大学生, 在长时加工条件下, 两个民族的大学生的语境促进效应并无显著差异。在短时加工条件下, 仅汉族大学生可以有效地抑制无关信息的干扰; 在长时加工条件下, 两个民族的大学生均可以有效地抑制无关信息的干扰。整个研究表明, 在汉语歧义词消解中, 随着加工时间增加, 维吾尔族大学生的语境促进效应和对无关信息的抑制均可以达到与汉族大学生相近的水平。     

Negation in context: Evidence from the visual world paradigm

Literature assumes that negation is more difficult to understand than affirmation, but this might depend on the pragmatic context. The goal of this paper is to show that pragmatic knowledge modulates the unfolding processing of negation due to the previous activation of the negated situation. To test this, we used the visual world paradigm. In this task, we presented affirmative (e.g., her dad was rich) and negative sentences (e.g., her dad was not poor) while viewing two images of the affirmed and denied entities. The critical sentence in each item was preceded by one of three types of contexts: an inconsistent context (e.g., She supposed that her dad had little savings) that activates the negated situation (a poor man), a consistent context (e.g., She supposed that her dad had enough savings) that activates the actual situation (a rich man), or a neutral context (e.g., her dad lived on the other side of town) that activates neither of the two models previously suggested. The results corroborated our hypothesis. Pragmatics is implicated in the unfolding processing of negation. We found an increase in fixations on the target compared to the baseline for negative sentences at 800?ms in the neutral context, 600?ms in the inconsistent context, and 1450?ms in the consistent context. Thus, when the negated situation has been previously introduced via an inconsistent context, negation is facilitated.     

Context effects in word recognition: evidence for early interactive processing

This study investigated whether a prior context influenced lexical access as indexed by participants' electrophysiological response in the N1 from 132 to 192 ms poststimulus. Ambiguous, high-frequency (HF), and low-frequency (LF) words were presented in neutral and biasing contexts. Event-related potentials (ERPs) for ambiguous words were compared with those for unambiguous HF (word form) and LF (word meaning) control words. Word frequency effects in the N1 extended previous ERP findings. A marginal effect of context for LF words provided electrophysiological support for the context-by-frequency interaction shown in reaction time paradigms. In neutral context, responses to ambiguous words were comparable to responses to HF words, and in biasing context (where context instantiated the subordinate sense), responses to ambiguous words were comparable to responses to LF words. The results establish temporal parameters for the early operation of context in lexical access. These constraints are more consistent with an interactive than a modular account.     

Contextual information modulates initial processes of syntactic integration: the role of inter- versus intrasentential predictions

The authors demonstrate that intersentential context may influence syntactic integration processes during online sentence comprehension, although this influence appears to be restricted to cases in which a contextual requirement must be fulfilled. By applying event-related brain potentials to the processing of clause-medial word order variations in German, the authors show that the local processing difficulty (a negativity from 300 to 450 ms) observed for object-initial sentences in a neutral context is also obtained in a (behaviorally) facilitating context in which the object is contextually given. By contrast, the processing pattern for a focused (questioned) initial object does not differ from that for a focused subject: both elicit a parietal positivity (280-480 ms) post-onset of the focused phrase. The authors interpret this early positivity as a general marker of focus integration, a process that appears to briefly supersede sentence-internal requirements.     

Musical metaphors: Evidence for a spatial grounding of non-literal sentences describing auditory events

This study investigated whether the spatial terms high and low, when used in sentence contexts implying a non-literal interpretation, trigger similar spatial associations as would have been expected from the literal meaning of the words. In three experiments, participants read sentences describing either a high or a low auditory event (e.g., The soprano sings a high aria vs. The pianist plays a low note). In all Experiments, participants were asked to judge (yes/no) whether the sentences were meaningful by means of up/down (Experiments 1 and 2) or left/right (Experiment 3) key press responses. Contrary to previous studies reporting that metaphorical language understanding differs from literal language understanding with regard to simulation effects, the results show compatibility effects between sentence implied pitch height and response location. The results are in line with grounded models of language comprehension proposing that sensory motor experiences are being elicited when processing literal as well as non-literal sentences.     

Support for context effects on segmentation and segments depends on the context

Listeners must adapt to differences in speech rate across talkers and situations. Speech rate adaptation effects are strong for adjacent syllables (i.e., proximal syllables). For studies that have assessed adaptation effects on speech rate information more than one syllable removed from a point of ambiguity in speech (i.e., distal syllables), the difference in strength between different types of ambiguity is stark. Studies of word segmentation have shown large shifts in perception as a result of distal rate manipulations, while studies of segmental perception have shown only weak, or even nonexistent, effects. However, no study has standardized methods and materials to study context effects for both types of ambiguity simultaneously. Here, a set of sentences was created that differed as minimally as possible except for whether the sentences were ambiguous to the voicing of a consonant or ambiguous to the location of a word boundary. The sentences were then rate-modified to slow down the distal context speech rate to various extents, dependent on three different definitions of distal context that were adapted from previous experiments, along with a manipulation of proximal context to assess whether proximal effects were comparable across ambiguity types. The results indicate that the definition of distal influenced the extent of distal rate effects strongly for both segments and segmentation. They also establish the presence of distal rate effects on word-final segments for the first time. These results were replicated, with some caveats regarding the perception of individual segments, in an Internet-based sample recruited from Mechanical Turk.     

Hemispheric asymmetries in meaning selection: Evidence from the disambiguation of homophonic vs. heterophonic homographs

Research investigating hemispheric asymmetries in meaning selection using homophonic homographs (e.g., bank), suggests that the left hemisphere (LH) quickly selects contextually relevant meanings, whereas the right hemisphere (RH) maintains a broader spectrum of meanings including those that are contextually irrelevant (e.g., Faust & Chiarello, 1998). The present study investigated cerebral asymmetries in maintaining the multiple meanings of two types of Hebrew homographs: homophonic homographs and heterophonic homographs (e.g., tear). Participants read homographs preceded by a biasing, or a non-biasing sentential context, and performed a lexical decision task on targets presented laterally, 1000 ms after the onset of the sentence-final ambiguous prime. Targets were related to either the dominant or the subordinate meaning of the preceding homograph, or unrelated to it. When targets were presented in the LVF/RH, dominant and subordinate meanings, of both types of homographs, were retained only when they were supported by context. In a non-biasing context, only dominant meanings of homophonic homographs were retained. Alternatively, when targets were presented in the RVF/LH, priming effects for homophonic homographs were only evident when meanings were supported by both context and frequency (i.e., when context favored the dominant meaning). In contrast, heterophonic homographs resulted in activation of dominant meanings, in all contexts, and activation of subordinate meanings, only in subordinate-biasing contexts. The results challenge the view that a broader spectrum of meanings is maintained in the right than in the left hemisphere and suggest that hemispheric differences in the time course of meaning selection (or decay) may be modulated by phonology.     

The Time-Course of Metaphor Comprehension: An Event-Related Potential Study

ERPs were recorded while subjects were reading short familiar metaphors (e.g., Those fighters are lions), unfamiliar metaphors (Those apprentices are lions), or literal control sentences (Those animals are lions) presented in isolation or preceded by either an irrelevant or relevant context (e.g., They are not idiotic: . . . .” vs. “They are not cowardly: Those fighters are lions”). The terminal word of metaphors elicited larger N400 components than did the terminal word of literal sentences (Experiment 1) suggesting that the (incongruous) literal meaning of metaphors was indeed accessed at some point during comprehension. The analysis of the 600–1000 and 1000–1400 latency bands (Late Positive Components) revealed no significant difference between metaphors and literal sentences. The manipulation of metaphor difficulty (Experiments 2 and 3) also failed to reveal any late effect specifically linked to metaphorical processing. Finally, an effect of the preceding sentence context was found in Experiments 3 and 4, as early as 300 ms following the terminal word onset. Overall, these results support a context-dependent account of metaphor comprehension stating that when contextually relevant, the metaphorical meaning is the only one accessed.     

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。