Wouter Duyck

Can Chunk Size Differences Explain Developmental Changes in Lexical Learning

In three experiments, we investigated Hebb repetition learning (HRL) differences between children and adults, as a function of the type of item (lexical vs. sub-lexical) and the level of item-overlap between sequences. In a first experiment, it was shown that when non-repeating and repeating (Hebb) sequences of words were all permutations of the same words, HRL was slower than when the sequences shared no words. This item-overlap effect was observed in both children and adults. In a second experiment, we used syllable sequences and we observed reduced HRL due to item-overlap only in children. The findings are explained within a chunking account of the HRL effect on the basis of which we hypothesize that children, compared with adults, chunk syllable sequences in smaller units. By hypothesis, small chunks are more prone to interference from anagram representations included in the filler sequences, potentially explaining the item-overlap effect in children. This hypothesis was tested in a third experiment with adults where we experimentally manipulated the chunk size by embedding pauses in the syllable sequences. Interestingly, we showed that imposing a small chunk size caused adults to show the same behavioral effects as those observed in children. Departing from the analogy between verbal HRL and lexical development, the results are discussed in light of the less-is-more hypothesis of age-related differences in language acquisition.

WordGen: A tool for word selection and nonword generation in Dutch, English, German, and French

WordGen is an easy-to-use program that uses the CELEX and Lexique lexical databases for word selection and nonword generation in Dutch, English, German, and French. Items can be generated in these four languages, specifying any combination of seven linguistic constraints: number of letters, neighborhood size, frequency, summated position-nonspecific bigram frequency, minimum position-nonspecific bigram frequency, position-specific frequency of the initial and final bigram, and orthographic relatedness. The program also has a module to calculate the respective values of these variables for items that have already been constructed, either with the program or taken from earlier studies. Stimulus queries can be entered through WordGen’s graphical user interface or by means of batch files. WordGen is especially useful for (1) Dutch and German item generation, because no such stimulus-selection tool exists for these languages, (2) the generation of nonwords for all four languages, because our program has some important advantages over previous nonword generation approaches, and (3) psycholinguistic experiments on bilingualism, because the possibility of using the same tool for different languages increases the cross-linguistic comparability of the generated item lists. WordGen is free and available athttp://expsy.ugent.be/wordgen.htm.

Visual Word Recognition by Bilinguals in a Sentence Context: Evidence for Nonselective Lexical Access

Recent research on bilingualism has shown that lexical access in visual word recognition by bilinguals is not selective with respect to language. In the present study, the authors investigated language-independent lexical access in bilinguals reading sentences, which constitutes a strong unilingual linguistic context. In the first experiment, Dutch-English bilinguals performing a 2nd language (L2) lexical decision task were faster to recognize identical and nonidentical cognate words (e.g., banaan-banana) presented in isolation than control words. A second experiment replicated this effect when the same set of cognates was presented as the final words of low-constraint sentences. In a third experiment that used eyetracking, the authors showed that early target reading time measures also yield cognate facilitation but only for identical cognates. These results suggest that a sentence context may influence, but does not nullify, cross-lingual lexical interactions during early visual word recognition by bilinguals.

Does bilingualism change native-language reading? Cognate effects in a sentence context.

Becoming a bilingual can change a persons cognitive functioning and language processing in a number of ways. This study focused on how knowledge of a second language influences how people read sentences written in their native language. We used the cognate-facilitation effect as a marker of cross-lingual activations in both languages. Cognates (e.g., Dutch-English schip [ship]) and controls were presented in a sentence context, and eye movements were monitored. Results showed faster reading times for cognates than for controls. Thus, this study shows that one of peoples most automated skills, reading in ones native language, is changed by the knowledge of a second language.

Frequency Drives Lexical Access in Reading but Not in Speaking: The Frequency-Lag Hypothesis

To contrast mechanisms of lexical access in production versus comprehension we compared the effects of word frequency (high, low), context (none, low constraint, high constraint), and level of English proficiency (monolingual, Spanish-English bilingual, Dutch-English bilingual) on picture naming, lexical decision, and eye fixation times. Semantic constraint effects were larger in production than in reading. Frequency effects were larger in production than in reading without constraining context but larger in reading than in production with constraining context. Bilingual disadvantages were modulated by frequency in production but not in eye fixation times, were not smaller in low-constraint contexts, and were reduced by high-constraint contexts only in production and only at the lowest level of English proficiency. These results challenge existing accounts of bilingual disadvantages and reveal fundamentally different processes during lexical access across modalities, entailing a primarily semantically driven search in production but a frequency-driven search in comprehension. The apparently more interactive process in production than comprehension could simply reflect a greater number of frequency-sensitive processing stages in production.

Is it time to leave behind the Revised Hierarchical Model of bilingual language processing after fifteen years of service

The Revised Hierarchical Model (RHM) of bilingual language processing dominates current thinking on bilingual language processing. Recently, basic tenets of the model have been called into question. First, there is little evidence for separate lexicons. Second, there is little evidence for language selective access. Third, the inclusion of excitatory connections between translation equivalents at the lexical level is likely to impede word recognition. Fourth, the connections between L2 words and their meanings are stronger than proposed in RHM. And finally, there is good evidence to make a distinction between language-dependent and language-independent semantic features. It is argued that the Revised Hierarchical Model cannot easily be adapted to incorporate these challenges and that a more fruitful way forward is to start from existing computational models of monolingual language processing and see how they can be adapted for bilingual input and output, as has been done in the Bilingual Interactive Activation model.

Semantic and translation priming from a first language to a second and back: Making sense of the findings

The present study investigated cross-language priming effects with unique noncognate translation pairs. Unbalanced Dutch (first language [L1])-English (second language [L2]) bilinguals performed a lexical decision task in a masked priming paradigm. The results of two experiments showed significant translation priming from L1 to L2 (meisje-GIRL) and from L2 to L1 (girl-MEISJE), using two different stimulus onset asynchronies (SOAs) (250 and 100 msec). Although translation priming from L1 to L2 was significantly stronger than priming from L2 to L1, the latter was significant as well. Two further experiments with the same word targets showed significant cross-language semantic priming in both directions ( jongen [boy]-GIRL; boy-MEISJE [GIRL]) and for both SOAs. These data suggest that L1 and L2 are represented by means of a similar lexico-semantic architecture in which L2 words are also able to rapidly activate semantic information, although to a lesser extent than L1 words are able to. This is consistent with models assuming quantitative rather than qualitative differences between L1 and L2 representations.

Translation and Associative Priming with Cross-Lingual Pseudohomophones: Evidence for Nonselective Phonological Activation in Bilinguals.

Using a lexical-decision task performed by Dutch-English bilinguals, the author showed that the recognition of visually presented first language (L1; e.g., touw) and second language (L2; e.g., back) targets is facilitated by L2 and L1 masked primes, respectively, which are pseudohomophones (roap and ruch) of the targets translation equivalent (rope and rug). Moreover, recognition of L2 targets (e.g., church) was also facilitated by L1 pseudohomophones (pous) of related words (paus [pope]). Contrastingly, no priming was observed for L1 targets (e.g., been [leg]) and L2 pseudohomophone associative primes (knea). Finally, the author found that an L2 target word (e.g., corner) is facilitated by a more frequent L2 (intralingual) homophone (e.g., hook) of its L1 translation equivalent (hoek). These findings strongly suggest language-independent activation of phonological representations in bilinguals and are compatible with the temporal delay assumption of the bilingual interactive activation plus model (A. Dijkstra & W. Van Heuven, 2002).

Forward and Backward Number Translation Requires Conceptual Mediation in Both Balanced and Unbalanced Bilinguals.

It is much debated whether translation is semantically mediated or based on word-word associations at the lexical level. In 2 experiments with Dutch (L1)-French (L2) bilinguals, the authors showed that there is a semantic number magnitude effect in both forward and backward translation of number words: It takes longer to translate number words representing large quantities (e.g., acht, huit [eight]) than small quantities (e.g., twee, deux [two]). In a 3rd experiment, the authors replicated these effects with number words that had been acquired only just before the translation task. Finally, it was shown that the findings were not due to the restricted semantic context of the stimuli. These findings strongly suggest that translation processes can be semantically mediated in both directions, even at low levels of L2 proficiency.

The frequency effect in second-language visual word recognition

A lexical decision experiment with Dutch-English bilinguals compared the effect of word frequency on visual word recognition in the first language with that in the second language. Bilinguals showed a considerably larger frequency effect in their second language, even though corpus frequency was matched across languages. Experiment 2 tested monolingual, native speakers of English on the English materials from Experiment 1. This yielded a frequency effect comparable to that of the bilinguals in Dutch (their L1). These results constrain the way in which existing models of word recognition can be extended to unbalanced bilingualism. In particular, the results are compatible with a theory by which the frequency effect originates from implicit learning. They are also compatible with models that attribute frequency effects to serial search in frequency-ordered bins (Murray & Forster, 2004), if these models are extended with the assumption that scanning speed is language dependent, or that bins are not language specific.