Semantic facilitation and lexical access during sentence processing

An experiment was conducted testing predictions derived from context-dependent and context-independent models of lexical access. Four types of unambiguous test sentences were constructed. The direct object of each test sentence was preceded by a verb that was either semantically related or unrelated to it, and by an adjective that was semantically related or unrelated. Context-dependent models predict that the speed with which the object noun is retrieved from the mental lexicon will be faster when the verb and/or the adjective is semantically related; context-independent models predict no such facilitation. Forty-four subjects each heard 32 test sentences and were asked to monitor within the sentence for a word-initial target phoneme. The target phoneme occurred on the word following the object noun. Reaction times to detect the targets were obtained. According to context-dependent models, these times should be shorter when related words precede the object noun, and that is what was found. It was also observed that the facilitation effects due to the related verbs and adjectives were additive. Implications of these results were discussed.     

Measuring lexical access during sentence processing

The results from “on-line” investigations of sentence comprehension are often difficult to interpret since it is not always apparent what component processes are reflected in the response measure. The results of two experiments reported here indicate that response latencies from phoneme-triggered lexical decision (PTLD) reflect the time needed for lexical access during sentence processing. Listeners were presented with sentences and were asked to make a word/nonword judgment for items beginning with a particular word-initial target phoneme. Speed of lexical access was manipulated by varying the semantic predictability of the target-bearing word. WORD judgments were faster for words that were preceded by semantically related verbs than were WORD judgments for words that were preceded by neutral verbs. The present results are consistent with other studies showing semantic facilitation of lexical access during the processing of fluent speech. It is argued that the phoneme-triggered lexical-decision task is a more suitable measure of lexical access during sentence processing than phoneme monitoring (Foss, 1969) or word monitoring (Marslen-Wilson & Tyler, 19751. In addition, it is pointed out that the phoneme-triggered lexical-decision task lends itself to modifications which should enable investigators to study various aspects of on-line sentence processing.     

Context and lexical access: implications of nonword interference for lexical ambiguity resolution

To eliminate potential "backward" priming effects, Glucksberg, Kreuz, and Rho (1986) introduced a variant of the cross-modal lexical priming task in which subjects made lexical decisions to nonword targets that were modeled on a word related to either the contextually biased or unbiased sense of an ambiguous word. Lexical decisions to nonwords were longer than controls only when the nonword was related to the contextually biased sense of the ambiguous word, leading Glucksberg et al. to conclude that context does constrain lexical access and that the multiple access pattern observed in previous studies was probably an artifact of backward priming. We did not find nonword interference when the nonword targets used by Glucksberg et al. were preceded by semantically related ambiguous or unambiguous word primes. However, we did replicate their sentence context results when the ambiguous words were removed from the sentences. We conclude that the interference obtained by Glucksberg et al. is due to postlexical judgements of the congruence of the sentence context and the target, not to context constraining lexical access.     

Lexical decision in sentences: Effects of syntactic structure

A lexical decision paradigm was used to examine syntactic influence on word recognition in sentences. Initial fragments of sentences were presented visually (CRT display) one word at a time (at reading speeds), from left to right. The string terminated with the appearance of a lexical decision target. The grammatical structure of the incomplete sentence affected lexical decision reaction time (RT). In Experiment 1, modal verb contexts followed by main verb targets and preposition contexts followed by noun targets produced lower RTs than did the opposite pairings (i.e., modal/noun and preposition/verb). In Experiment 2, transitive verb contexts followed by noun targets and subject noun phrase contexts followed by verb targets yielded lower RTs than did the opposite pairings. Similar contrasts for adjective targets did not yield comparable effects in Experiment 2, but did when the adjective was the head of a predictable phrase (Experiment 4). In Experiment 3, noun targets yielded lower RTs than did verb targets after contexts of a transitive verb followed by a prepositional phrase. An account of these effects is offered in terms of parsing constraints on phrasal categories.     

Typicality effects in picture‐word interference paradigm: An evaluation of the response exclusion hypothesis

The response exclusion hypothesis suggests that the polarity of semantic effects in the picture‐word interference paradigm is determined by the response‐relevant criteria. Semantic interference effects would be observed when semantically related distractor words satisfy the response‐relevant criteria; otherwise, semantic facilitation effects should be found. The purpose of this study was to further evaluate the response exclusion hypothesis by exploring the typicality effects in pictures naming. In two experiments, pictures of objects were named either in the context of verb distractor words with different typicality of passive functions or in the context of adjective distractor words with different typicality of characteristics. Facilitation effects were observed in context of typical verbs and adjectives, while interference effects were observed in the context of atypical verbs and adjectives. Given that neither typical nor atypical distractor words satisfy the response‐relevant criteria to produce noun, these findings are problematic for the response exclusion hypothesis. Role of syntagmatic relationships in lexical retrieval was invoked to explain present findings.     

Planning at the Phonological Level during Sentence Production

In two picture–word interference experiments we examined whether phrase boundaries affected how far in advance speakers plan the sounds of words during sentence production. Participants produced sentences of varying lengths (short determiner + noun + verb or long determiner + adjective + noun + verb) while ignoring phonologically related and unrelated words to the verb of the sentence. Response times to begin producing both types of sentences were faster in the presence of a related versus unrelated distractor. The results suggest that the activation of phonological properties of words outside the first phrase and first and second phonological word affect onset of articulation during sentence production. The results are discussed in the light of previous evidence of phonological planning during multi-word production. Implications for the phonological facilitation effect in the picture–word interference paradigm are also discussed.The research reported in this article served as partial fulfillment of the requirements for the PhD degree at Harvard University for Tatiana T. Schnur     

Priming nouns and verbs: differential influences of semantic and grammatical cues in the two cerebral hemispheres

The current experiment investigated how sentential form-class expectancies influenced lexical-semantic priming within each hemisphere. Sentences were presented that led readers to expect a noun or a verb and the sentence-final target word was presented to one visual field/hemisphere for a lexical decision response. Noun and verb targets in the semantically related condition were compared to an unrelated prime condition, which also predicted part of speech but did not contain any lexical-semantic associates of the target word. The semantic priming effect was strongly modulated by form-class expectancy for RVF/LH targets, for both nouns and verbs. In the LVF/RH, semantic priming was obtained in all conditions, regardless of whether the form-class expectancy was violated. However, the nouns that were preceded by a noun-predicting sentence showed an extremely high priming value in the LVF/RH, suggesting that the RH may have some sensitivity to grammatical predictions for nouns. Comparisons of LVF/RH priming to calculations derived from the LSA model of language representation, which does not utilize word order, suggested that the RH might derive message-level meaning primarily from lexical-semantic relatedness.     

Phonological recoding and context

This paper reports an experiment in which lexical decision times for words with irregular spelling-to-sound correspondence (e.g., GAUGE) and matched regular words (e.g., GRILL) were measured under two conditions: priming, in which each target was preceded by a semantically related word, and a control condition, in which each target was preceded by an asterisk. The results showed that lexical decision times were significantly longer for irregular words and that lexical decision times were significantly faster in the priming condition. There was no interaction between these two factors, indicating that these two variables have an additive effect on lexical decision speed. The experiment therefore extends the range of conditions under which word regularity effects can be demonstrated and suggests that the phonological component of the lexical access process is uninfluenced by the provision of semantic context. The nature of regularity effects with regard to lexical decision is also briefly discussed.     

Priming and the effects of sentence and lexical contexts on naming time: Evidence for autonomous lexical processing

Models of language processing which stress the autonomy of processing at each level predict that the semantic properties of an incomplete sentence context should have no influence on lexical processing, either facilitatory or inhibitory. An experiment similar to those reported by Fischler and Bloom (1979) and Stanovich and West (1979, 1981) was conducted using naming time as an index of lexical access time. No facilitatory effects of context were observed for either highly predictable or semantically appropriate (but unpredictable) completions, whereas strong inhibitory effects were obtained for inappropriate completions. When lexical decision time was the dependent measure, the same results were obtained, except that predictable completions now produced strong facilitation. In a further experiment the inhibitory effects of context on lexical decision times for inappropriate targets were maintained, even though unfocussed contexts were used, in which no clear expectancy for a particular completion was involved. These results were interpreted in terms of a two-factor theory which attributes the facilitation observed with the lexical decision task to postaccess decision processes which are not involved in the naming task. The inhibitory effects were attributed to interference resulting from semantic integration. In contrast to the results for sentence contexts, lexical contexts of the doctor-nurse variety produced clear facilitation effects on naming time (but no inhibitory effects). It was also shown that relatively minor variations in the type of neutral context could completely alter the relative importance of facilitation and inhibition.     

Differences in semantic encoding as a function of reading comprehension skill

Using a modified Stroop procedure, we examined the extent to which the semantic encoding of a word is governed by the context within which that word appears. Good and poor comprehenders named the color of target words following their reading of either sentences or single words representing the object nouns of the sentences. Target words represented contextually emphasized (appropriate) attributes of the object nouns, nonemphasized (inappropriate) attributes of these nouns, or object attributes not related to these nouns (neutral). For single-word contexts, all subjects exhibited equal semantic interference to appropriate and inappropriate targets, relative to neutral targets. For sentence contexts, however, good comprehenders exhibited semantic interference only to appropriate targets, whereas poor comprehenders again exhibited equal interference to appropriate and inappropriate targets. These findings suggest that differences in comprehension skill may be attributable, at least in part, to fundamental differences in the way in which sentences are semantically encoded.     

The generalizability of context effects on word recognition: A reconsideration of the roles of parafoveal priming and sentence context

In three experiments, subjects named target words preceded by congruous, incongruous, or neutral sentence contexts. There was no evidence that the recognition of the target word was affected by the semantic characteristics of a word presented immediately to the right of it. The nature of the preceding sentence context did affect target-naming speed. However, the magnitude of the context effect was considerably smaller in these experiments, in which nonterminal target words were used, than in previous experiments in which the target word was always the final word of the sentence, was highly predictable from the context, and was often semantically related to words in the sentence. The implications of these two findings for theories of reading and context effects are discussed.     

汉语句子可继续性对句子理解加工的即时影响

通过操纵动词与后接词的关系,来产生搭配异常并控制句子的可继续性,研究汉语词汇信息在句子加工中的即时作用。实验一利用跨通道技术,发现动一名词搭配异常对目标名词的加工有即时影响,形容词条件下可继续性对目标形容词的加工有即时影响;实验二采用眼动技术,发现名词条件和形容词条件下可继续性均有显著的即时影响。结果显示,语义等多种词汇信息被通达后立即共同参与了汉语句子加工。     

Pictures in sentences: understanding without words

To understand a sentence, the meanings of the words in the sentence must be retrieved and combined. Are these meanings represented within the language system (the lexical hypothesis) or are they represented in a general conceptual system that is not restricted to language (the conceptual hypothesis)? To evaluate these hypotheses, sentences were presented in which a pictured object replaced a word (rebus sentences). Previous research has shown that isolated pictures and words are processed equally rapidly in conceptual tasks, but that pictures are markedly slower than words in tasks requiring lexical access. The lexical hypothesis would therefore lead one to expect that rebus sentences will be relatively difficult, whereas the conceptual hypothesis would predict that rebus sentences would be rather easy. Sentences were shown using rapid serial visual presentation (RSVP) at a rate of 10 or 12 words per second. With one set of materials (Experiments 1 and 2), readers took longer to judge the plausibility of rebus sentences than all-word sentences, although the accuracy of judgment and of recall were similar for the two formats. With two new sets of materials (Experiments 3 and 5), rebus and all-word sentences were virtually equivalent except in one circumstance: when a picture replaced the noun in a familiar phrase such as seedless grapes. In contrast, when the task required overt naming of the rebus picture in a sentence context, latency to name the picture was markedly longer than to name the corresponding word, and the appropriateness of the sentence context affected picture naming but not word naming (Experiment 4). The results fail to support theories that place word meanings in a specialized lexical entry. Instead, the results suggest that the lexical representation of a noun or familiar noun phrase provides a pointer to a nonlinguistic conceptual system, and it is in that system that the meaning of a sentence is constructed.     

On obtaining episodic priming in a lexical decision task following paired-associate learning

In four experiments, subjects made lexical (word-nonword) decisions to target letter strings after studying paired associates. In this lexical decision test, word targets previously studied as response terms in the paired associates were preceded at a 150-ms and/or 950-ms stimulus onset asynchrony (SOA) by one of various subsets of the following six types of primes: a neutral (XXX or ready) prime, a semantically unrelated word prime episodically related to the target through its having been previously studied in the same pair, a semantically related word prime previously studied in a pair with some other unrelated word, a semantically unrelated word prime previously studied in a pair with some other unrelated word, a nonstudied semantically related word prime, and a nonstudied semantically unrelated word prime. At the 950-ms SOA, facilitation of lexical decisions produced by the episodically related primes was greater in test lists in which there were no 150-ms SOA trials intermixed, no previously studied semantically related primes, and no studied nonword targets. At the 150-ms SOA, facilitation from episodic priming was greater in test lists in which there were no semantically related primes and all studied word targets and no studied nonword targets. Facilitation effects from semantically related primes were small in magnitude and occurred inconsistently. Discussion focused on the implications these results have for the episodic-semantic memory distinction and the automaticity of episodic and semantic priming effects.     

Semantic representation and surface forms: A look at across-language priming in bilinguals

The question of whether words in one language versus their translations in another access the same conceptual representation was addressed in the present experiment. English-French bilinguals were tested in a lexical decision task, the target words being primed by semantically related words in either the same language or across languages. The results show significant priming facilitation in both conditions; response latencies were notably shorter when the target was preceded by a semantically related word than when presented alone, whether or not the two words were presented in the same language. While these results seem to substantiate the hypothesis of a common semantic store for the two languages, close inspection reveals that facilitation was more likely due to the strategic use of primes than to automatic processing.     

Vertical similarity in spoken word recognition: Multiple lexical activation,individual differences,and the role of sentence context

Four experiments investigated acoustic-phonetic similarity in the mapping process between the speech signal and lexical representations (vertical similarity). Auditory stimuli were used where ambiguous initial phonemes rendered a phoneme sequence lexically ambiguous (perceptual-lexical ambiguities). A cross-modal priming paradigm (Experiments 1, 2, and 3) showed facilitation for targets related to both interpretations of the ambiguities, indicating multiple activation. Experiment 4 investigated individual differences and the role of sentence context in vertical similarity mapping. The results support a model where spoken word recognition proceeds via goodness-of-fit mapping between speech and lexical representations that is not influenced by sentence context.     

Phoneme monitoring and lexical processing: Evidence for associative context effects

In this paper, we propose a new version of the phoneme monitoring task that is well-suited for the study of lexical processing. The generalized phoneme monitoring (GPM) task, in which subjects detect target phonemes appearing anywhere in the test words, was shown to be sensitive to associative context effects. In Experiment 1, using the standard phoneme monitoring procedure in which subjects detect only word-initial targets, no effect of associative context was obtained. In contrast, clear context effects were observed in Experiment 2, which used the GPM task. Subjects responded faster to word-initial and word-medial targets when the target-bearing words were preceded by an associatively related word than when preceded by an unrelated one. The differential effect of context in the two versions of the phoneme monitoring task was interpreted with reference to task demands and their role in directing selective attention. Experiment 3 showed that the size of the context effect was unaffected by the proportion of related words in the experiment, suggesting that the observed effects were not due to subject strategies.     

The role of grammatical class on word recognition

The double dissociation between noun and verb processing, well documented in the neuropsychological literature, has not been supported in imaging studies. Recent imaging studies, in fact, suggest that once confounding with semantics is eliminated, grammatical class effects only emerge as a consequence of building frames. Here we assess this hypothesis behaviorally in two visual word recognition experiments. In Experiment 1, participants made lexical decisions on verb targets. We manipulated the grammatical class of the prime words (either nouns or verbs and always introduced in a minimal phrasal context, i.e., “the + N” or “to + V”), and their semantic similarity to a target (related vs. unrelated). We found reliable effects of grammatical class, and no interaction with semantic similarity. Experiment 2 further explored this grammatical class effect, using verb targets preceded by semantically unrelated verb vs. noun primes. In one condition, prime words were presented as bare words; in the other, they were presented in the minimal phrasal context used in Experiment 1. Grammatical class effects only arose in the latter but not in the former condition thus providing evidence that word recognition does not recruit grammatical class information unless it is provided to the system.     

How verbs can activate things: cross-language activation across word classes

The present study explored whether language-nonselective access in bilinguals occurs across word classes in a sentence context. Dutch–English bilinguals were auditorily presented with English (L2) sentences while looking at a visual world. The sentences contained interlingual homophones from distinct lexical categories (e.g., the English verb spoke, which overlaps phonologically with the Dutch noun for ghost, spook). Eye movement recordings showed that depictions of referents of the Dutch (L1) nouns attracted more visual attention than unrelated distractor pictures in sentences containing homophones. This finding shows that native language objects are activated during second language verb processing despite the structural information provided by the sentence context.     

Expectancy,integration, and interactional processes: Age differences in the nature of words affected by sentence context

Two experiments investigated sentence context effects on the naming times of sentence completion words by third-grade children and college students. Across both experiments, the largest age difference in contextual facilitation was obtained for highly predictable, best completion words. Pronounced age differences in facilitation effects were also present for semantically acceptable target words which were much less predictable in the sentence context than the best completion words. However, age differences in contextual facilitation were negligible for target words which were associatively related to the best completion word, but which were not also semantically acceptable in the sentence context. Thus, the semantic acceptability of the word in the sentence context had a much greater influence on children's as compared to adults' word identification times, both when the word was highly predictable, as well as when it was much less predictable in the sentence context.