Neural pattern similarity across concept exemplars predicts memory after a long delay.

The irregularities of the world ensure that each interaction we have with a concept is unique. In order to generalize across these unique encounters to form a high-level representation of a concept, we must draw on similarities between exemplars to form new conceptual knowledge that is maintained over a long time. Two neural similarity measures - pattern robustness and encoding-retrieval similarity - are particularly important for predicting memory outcomes. In this study, we used fMRI to measure activity patterns while people encoded and retrieved novel pairings between unfamiliar (Dutch) words and visually presented animal species. We address two underexplored questions: 1) whether neural similarity measures can predict memory outcomes, despite perceptual variability between presentations of a concept and 2) if pattern similarity measures can predict subsequent memory over a long delay (i.e., one month). Our findings indicate that pattern robustness during encoding in brain regions that include parietal and medial temporal areas is an important predictor of subsequent memory. In addition, we found significant encoding-retrieval similarity in the left ventrolateral prefrontal cortex after a month's delay. These findings demonstrate that pattern similarity is an important predictor of memory for novel word-animal pairings even when the concept includes multiple exemplars. Importantly, we show that established predictive relationships between pattern similarity and subsequent memory do not require visually identical stimuli (i.e., are not simply due to low-level visual overlap between stimulus presentations) and are maintained over a month.

The complex interactions of context availability, polysemy, word frequency, and orthographic variables during lexical processing.

In this study we examined the interactions of context availability, polysemy, word frequency, and orthographic neighborhood variables during lexical processing. Context availability and polysemy interacted, in that words that were both lower in context availability and had fewer related senses were especially disadvantaged, as was originally reported by Tokowicz and Kroll (2007). Word frequency interacted with both polysemy and context availability, in that the effects of polysemy and context availability were stronger for lower-frequency words. Finally, orthographic neighborhood size and frequency both interacted with polysemy: the effect of polysemy was greater for words with smaller orthographic neighborhoods and a greater number of higher-frequency neighbors. These findings provide support for the context availability hypothesis (Schwanenflugel & Shoben, 1983). Specifically, the feedback activation account (Hino & Lupker, 1996) offers a mechanistic explanation of our findings that is rooted in feedback from semantic to orthographic representations.

The consequences of language proficiency and difficulty of lexical access for translation performance and priming.

Repetition priming was used to assess how proficiency and the ease or difficulty of lexical access influence bilingual translation. Two experiments, conducted at different universities with different Spanish-English bilingual populations and materials, showed repetition priming in word translation for same-direction and different-direction repetitions. Experiment 1, conducted in an English-dominant environment, revealed an effect of translation direction but not of direction match, whereas Experiment 2, conducted in a more balanced bilingual environment, showed an effect of direction match but not of translation direction. A combined analysis on the items common to both studies revealed that bilingual proficiency was negatively associated with response time (RT), priming, and the degree of translation asymmetry in RTs and priming. An item analysis showed that item difficulty was positively associated with RTs, priming, and the benefit of same-direction over different-direction repetition. Thus, although both participant accuracy and item accuracy are indices of learning, they have distinct effects on translation RTs and on the learning that is captured by the repetition-priming paradigm.

Cross-language influences: translation status affects intraword sense relatedness.

Many words have more than one meaning, and these meanings vary in their degree of relatedness. In the present experiment, we examined whether this degree of relatedness is influenced by whether or not the two meanings share a translation in a bilingual's other language. Native English speakers with Spanish as a second language (i.e., English-Spanish bilinguals) and native Spanish speakers with English as a second language (i.e., Spanish-English bilinguals) were presented with pairs of phrases instantiating different senses of ambiguous English words (e.g., dinner date-expiration date) and were asked to decide whether the two senses were related in meaning. Critically, for some pairs of phrases, a single Spanish translation encompassed both meanings of the ambiguous word (joint-translation condition; e.g., mercado in Spanish refers to both a flea market and the housing market), but for others, each sense corresponded to a different Spanish translation (split-translation condition; e.g., cita in Spanish refers to a dinner date, but fecha refers to an expiration date). The proportions of "yes" (related) responses revealed that, relative to monolingual English speakers, Spanish-English bilinguals consider joint-translation senses to be less related than split-translation senses. These findings exemplify semantic cross-language influences from a first to a second language and reveal the semantic structure of the bilingual lexicon.

eDom: norming software and relative meaning frequencies for 544 English homonyms.

Words that are homonyms-that is, for which a single written and spoken form is associated with multiple, unrelated interpretations, such as COMPOUND, which can denote an < enclosure > or a < composite > meaning-are an invaluable class of items for studying word and discourse comprehension. When using homonyms as stimuli, it is critical to control for the relative frequencies of each interpretation, because this variable can drastically alter the empirical effects of homonymy. Currently, the standard method for estimating these frequencies is based on the classification of free associates generated for a homonym, but this approach is both assumption-laden and resource-demanding. Here, we outline an alternative norming methodology based on explicit ratings of the relative meaning frequencies of dictionary definitions. To evaluate this method, we collected and analyzed data in a norming study involving 544 English homonyms, using the eDom norming software that we developed for this purpose. Dictionary definitions were generally sufficient to exhaustively cover word meanings, and the methods converged on stable norms with fewer data and less effort on the part of the experimenter. The predictive validity of the norms was demonstrated in analyses of lexical decision data from the English Lexicon Project (Balota et al., Behavior Research Methods, 39, 445-459, 2007), and from Armstrong and Plaut (Proceedings of the 33rd Annual Meeting of the Cognitive Science Society, 2223-2228, 2011). On the basis of these results, our norming method obviates relying on the unsubstantiated assumptions involved in estimating relative meaning frequencies on the basis of classification of free associates. Additional details of the norming procedure, the meaning frequency norms, and the source code, standalone binaries, and user manual for the software are available at http://edom.cnbc.cmu.edu .

Determinants of translation ambiguity: A within and cross-language comparison.

Ambiguity in translation is highly prevalent, and has consequences for second-language learning and for bilingual lexical processing. To better understand this phenomenon, the current study compared the determinants of translation ambiguity across four sets of translation norms from English to Spanish, Dutch, German and Hebrew. The number of translations an English word received was correlated across these different languages, and was also correlated with the number of senses the word has in English, demonstrating that translation ambiguity is partially determined by within-language semantic ambiguity. For semantically-ambiguous English words, the probability of the different translations in Spanish and Hebrew was predicted by the meaning-dominance structure in English, beyond the influence of other lexical and semantic factors, for bilinguals translating from their L1, and translating from their L2. These findings are consistent with models postulating direct access to meaning from L2 words for moderately-proficient bilinguals.

How meaning similarity influences ambiguous word processing: the current state of the literature.

The majority of words in the English language do not correspond to a single meaning, but rather correspond to two or more unrelated meanings (i.e., are homonyms) or multiple related senses (i.e., are polysemes). It has been proposed that the different types of "semantically-ambiguous words" (i.e., words with more than one meaning) are processed and represented differently in the human mind. Several review papers and books have been written on the subject of semantic ambiguity (e.g., Adriaens, Small, Cottrell, & Tanenhaus, 1988; Burgess & Simpson, 1988; Degani & Tokowicz, 2010; Gorfein, 1989, 2001; Simpson, 1984). However, several more recent studies (e.g., Klein & Murphy, 2001; Klepousniotou, 2002; Klepousniotou & Baum, 2007; Rodd, Gaskell, & Marslen-Wilson, 2002) have investigated the role of the semantic similarity between the multiple meanings of ambiguous words on processing and representation, whereas this was not the emphasis of previous reviews of the literature. In this review, we focus on the current state of the semantic ambiguity literature that examines how different types of ambiguous words influence processing and representation. We analyze the consistent and inconsistent findings reported in the literature and how factors such as semantic similarity, meaning/sense frequency, task, timing, and modality affect ambiguous word processing. We discuss the findings with respect to recent parallel distributed processing (PDP) models of ambiguity processing (Armstrong & Plaut, 2008, 2011; Rodd, Gaskell, & Marslen-Wilson, 2004). Finally, we discuss how experience/instance-based models (e.g., Hintzman, 1986; Reichle & Perfetti, 2003) can inform a comprehensive understanding of semantic ambiguity resolution.

Cue strength in second-language processing: an eye-tracking study.

This study used eye-tracking and grammaticality judgement measures to examine how second-language (L2) learners process syntactic violations in English. Participants were native Arabic and native Mandarin Chinese speakers studying English as an L2, and monolingual English-speaking controls. The violations involved incorrect word order and differed in two ways predicted to be important by the unified competition model [UCM; MacWhinney, B. (2005). A unified model of language acquisition. In J. F. Kroll & A. M. B. de Groot (Eds.), Handbook of bilingualism: Psycholinguistic approaches (pp. 49-67). Oxford: Oxford University Press.]. First, one violation had more and stronger cues to ungrammaticality than the other. Second, the grammaticality of these word orders varied in Arabic and Mandarin Chinese. Sensitivity to violations was relatively quick overall, across all groups. Sensitivity also was related to the number and strength of cues to ungrammaticality regardless of native language, which is consistent with the general principles of the UCM. However, there was little evidence of cross-language transfer effects in either eye movements or grammaticality judgements.

Testing an assumption of the E-Z Reader model of eye-movement control during reading: using event-related potentials to examine the familiarity check.

According to the E-Z Reader model of eye-movement control, the completion of an early stage of lexical processing, the familiarity check, causes the eyes to move forward during reading (Reichle, Pollatsek, Fisher, & Rayner, 1998). Here, we report an event-related potential (ERP) experiment designed to examine the hypothesized familiarity check at the electrophysiological level. The results indicate ERP components modulated by word frequency at the time of the predicted familiarity check. These findings are consistent with the hypothesis that an early stage of lexical processing is linked to the "decisions" about when to move the eyes during reading.

Semantic ambiguity within and across languages: an integrative review.

Semantic ambiguity often occurs within a language (e.g., the word "organ" in English means both a body part and a musical instrument), but it can also cross a language boundary, such that a given word form is shared in two languages, but its meanings are different (e.g., the word "angel" means "sting" in Dutch). Bilingual individuals are therefore faced not only with ambiguity in each of their languages, but also with ambiguity across languages. The current review focuses on studies that explored such cross-language ambiguity and examines how the results from these studies can be integrated with what we have learned about within-language ambiguity resolution. In particular, this review examines how interactions of frequency and context manifest themselves in ambiguity that crosses a language boundary and call for the inclusion of language context as a contributing factor. An extension of the monolingual reordered access model (Duffy, Morris, & Rayner, 1988) is outlined to discuss the interactions between these factors. Furthermore, the effects of the similarity between the two meanings, task differences, and individual differences are explored. This review highlights the need for studies that test within- and cross-language ambiguity in the same individuals before strong conclusions can be made about the nature of interactions between frequency, semantic context, and language context.

The Revised Hierarchical Model: A critical review and assessment.

Brysbaert and Duyck (2009) suggest that it is time to abandon the Revised Hierarchical Model (Kroll and Stewart, 1994) in favor of connectionist models such as BIA+ (Dijkstra and Van Heuven, 2002) that more accurately account for the recent evidence on nonselective access in bilingual word recognition. In this brief response, we first review the history of the Revised Hierarchical Model (RHM), consider the set of issues that it was proposed to address, and then evaluate the evidence that supports and fails to support the initial claims of the model. Although 15 years of new research findings require a number of revisions to the RHM, we argue that the central issues to which the model was addressed, the way in which new lexical forms are mapped to meaning and the consequence of language learning history for lexical processing, cannot be accounted for solely within models of word recognition.

Are pumpkins better than heaven? An ERP investigation of order effects in the concrete-word advantage.

The present study investigated the cognitive and neural mechanisms underlying the processing of concrete and abstract words by recording event-related potentials (ERPs) while participants performed an English lexical decision task. Concrete and abstract words were presented in three stimulus-order conditions: abstract before concrete, concrete before abstract, and mixed. Beginning between 125 and 175 ms, nonwords elicited significantly more negative responses than real words. Between 300 and 500 ms, concrete words elicited significantly more negative responses than abstract words in the abstract-first and mixed conditions, but not in the concrete-first condition. We discuss our findings in relation to a feature activation framework and conclude that order of presentation provides a context for words that dynamically interacts with activation of a word's meaning features, thus allowing word order to modulate the concreteness effect.

Number-of-translation norms for Dutch-English translation pairs: a new tool for examining language production.

We collected number-of-translation norms on 562 Dutch-English translation pairs from several previous studies of cross-language processing. Participants were highly proficient Dutch-English bilinguals. Form and semantic similarity ratings were collected on the 1,003 possible translation pairs. Approximately 40% of the translations were rated as being similar across languages with respect to spelling/sound (i.e., they were cognates). Approximately 45% of the translations were rated as being highly semantically similar across languages. At least 25% of the words in each direction of translation had more than one translation. The form similarity ratings were found to be highly reliable even when obtained with different bilinguals and modified rating procedures. Number of translations and meaning factors significantly predicted the semantic similarity of translation pairs. In future research, these norms may be used to determine the number of translations of words to control for or study this factor. These norms are available at http://www.talkbank.org/norms/tokowicz/.