Ton Dijkstra

The architecture of the bilingual word recognition system: From identification to decision

The paper opens with an evaluation of the BIA model of bilingual word recognition in the light of recent empirical evidence. After pointing out problems and omissions, a new model, called the BIA+, is proposed. Structurally, this new model extends the old one by adding phonological and semantic lexical representations to the available orthographic ones, and assigns a different role to the so-called language nodes. Furthermore, it makes a distinction between the effects of non-linguistic context (such as instruction and stimulus list composition) and linguistic context (such as the semantic and syntactic effects of sentence context), based on a distinction between the word identification system itself and a task/decision system that regulates control. At the end of the paper, the generalizability of the BIA+ model to different tasks and modalities is discussed.

Foreign language knowledge can influence native language performance in exclusively native contexts

In three experiments, we studied the influence of foreign language knowledge on native language performance in an exclusively native language context. Trilinguals with Dutch as their native and dominant language (L1), English as their second language (L2), and French as their third language (L3) performed a word association task (Experiment 1) or a lexical decision task (Experiments 2 and 3) in L1. The L1 stimulus words were cognates with their translations in English, cognates with their translations in French, or were noncognates. In Experiments 1 and 2 with trilinguals who were highly proficient in English and relatively low in proficiency in French, we observed shorter word association and lexical decision times to the L1 words that were cognates with English than to the noncognates. In these relatively low-proficiency French speakers, response times (RTs) for the L1 words that were cognates with French did not differ from those for the noncognates. In Experiment 3, we tested Dutch-English- French trilinguals with a higher level of fluency in French (i.e., equally fluent in English and in French). We now observed faster responses on the L1 words that were cognates with French than on the noncognates. Lexical decision times to the cognates with English were also shorter than those to the noncognates. The results indicate that words presented in the dominant language, to naive participants, activate information in the nontarget, and weaker, language in parallel, implying that the multilinguals’ processing system is profoundly nonselective with respect to language. A minimal level of nontarget language fluency seems to be required, however, before any weaker language effects become noticeable in L1 processing.

Interlingual homograph recognition: Effects of task demands and language intermixing

A series of three lexical decision experiments showed that interlingual homographs may be recognized faster than, slower than, or as fast as monolingual control words depending on task requirements and language intermixing. In Experiment 1, Dutch bilingual participants performed an English lexical decision task including English/Dutch homographs, cognates, and purely English control words. Reaction times to interlingual homographs were unaffected by the frequency of the Dutch reading and did not differ from monolingual controls. In contrast, cognates were recognized faster than controls. In Experiment 2, Dutch participants again performed an English lexical decision task on homographs, but, apart from nonwords, Dutch words were included which required a “no” reaction. Strong inhibition effects were obtained which depended on the relative frequency difference of the two readings of the homograph. These turned into frequency-dependent facilitation effects in Experiment 3, where participants performed a general lexical decision task, responding “yes” if a word of either language was presented. It is argued that bilingual word recognition models can only account for the series of experiments if they explain how lexical processing is affected by task demands and stimulus list composition.

Theta Responses Are Involved in Lexical–Semantic Retrieval during Language Processing

Oscillatory neuronal dynamics, observed in the human electroencephalogram (EEG) during language processing, have been related to the dynamic formation of functionally coherent networks that serve the role of integrating the different sources of information needed for understanding the linguistic input. To further explore the functional role of oscillatory synchrony during language processing, we quantified event-related EEG power changes induced by the presentation of open-class (OC) words and closed-class (CC) words in a wide range of frequencies (from 1 to 30 Hz), while subjects read a short story. Word presentation induced three oscillatory components: a theta power increase (47 Hz), an alpha power decrease (10 12 Hz), and a beta power decrease (1621 Hz). Whereas the alpha and beta responses showed mainly quantitative differences between the two word classes, the theta responses showed qualitative differences between OC words and CC words: A theta power increase was found over left temporal areas for OC words, but not for CC words. The left temporal theta increase may index the activation of a network involved in retrieving the lexical semantic properties of the OC items.

Recognizing cognates and interlingual homographs: Effects of code similarity in language-specific and generalized lexical decision

In four experiments, we investigated how cross-linguistic overlap in semantics, orthography, and phonology affects bilingual word recognition in different variants of the lexical decision task. Dutch-English bilinguals performed a language-specific or a generalized lexical decision task including words that are spelled and/or pronounced the same in English and in Dutch and that matched one-language control words from both languages. In Experiments 1 and 3, “false friends” with different meanings in the two languages (e.g.,spot) were presented, whereas in Experiments 2 and 4 cognates with the same meanings across languages (e.g.,film) were presented. The language-specific Experiments 1 and 2 replicated and qualified an earlier study (Dijkstra, Grainger, & Van Heuven, 1999). In the generalized Experiment 3, participants reacted equally quickly on Dutch-English homographs and Dutch control words, indicating that their response was based primarily on the fastest available orthographic code (i.e., Dutch). In Experiment 4, cognates were recognized faster than English and Dutch controls, suggesting coactivation of the cognates’ semantics. The nonword results indicate that the bilingual rejection procedure can, to some extent, be language specific. All results are discussed within the BIA+ (bilingual interactive activation) model for bilingual word recognition.

Language Conflict in the Bilingual Brain

The large majority of humankind is more or less fluent in 2 or even more languages. This raises the fundamental question how the language network in the brain is organized such that the correct target language is selected at a particular occasion. Here we present behavioral and functional magnetic resonance imaging data showing that bilingual processing leads to language conflict in the bilingual brain even when the bilinguals’ task only required target language knowledge. This finding demonstrates that the bilingual brain cannot avoid language conflict, because words from the target and nontarget languages become automatically activated during reading. Importantly, stimulus-based language conflict was found in brain regions in the LIPC associated with phonological and semantic processing, whereas response-based language conflict was only found in the pre-supplementary motor area/anterior cingulate cortex when language conflict leads to response conflicts.

Three languages, one ECHO: Cognate effects in trilingual word recognition

Research on bilingual word recognition suggests that lexical access is non-selective with respect to language, i.e., that word representations of both languages become active during recognition. One piece of evidence is that bilinguals recognise cognates (words that are identical or similar in form and meaning in two languages) faster than non-cognates. The present study used cognates to investigate whether the non-selective access hypothesis holds also for trilinguals and three languages. Dutch-English-German trilinguals carried out a lexical decision task in their third language (German). The word materials included purely German control words, “double” cognates that overlapped in Dutch and German, but not in English, and “triple” cognates with the same form and meaning in Dutch, German, and English. Faster RTs were found for Dutch-German cognates than for control words, but additionally, “triple” cognates were processed even faster than “double” cognates. The “triple” cognate effect was not influenced by whether the participants had previously read an English text. A control experiment with German monolinguals confirmed that the effect was not an artifact of uncontrolled stimulus characteristics. Thus, independent of context, both the native language and another foreign non-target language influenced target language comprehension in trilinguals. This supports a view of language non-selective access implying all languages known to an individual may affect word activation and recognition.

Native Language Influences on Word Recognition in a Second Language: A Megastudy

Many studies have reported that word recognition in a second language (L2) is affected by the native language (L1). However, little is known about the role of the specific language combination of the bilinguals. To investigate this issue, the authors administered a word identification task (progressive demasking) on 1,025 monosyllabic English (L2) words to native speakers of French, German, and Dutch. A regression approach was adopted, including a large number of within- and between-language variables as predictors. A substantial overlap of reaction time patterns was found across the groups of bilinguals, showing that word recognition results obtained for one group of bilinguals generalize to bilinguals with different mother tongues. Moreover, among the set of significant predictors, only one between-language variable was present (cognate status); all others reflected characteristics of the target language. Thus, although influences across languages exist, word recognition in L2 by proficient bilinguals is primarily determined by within-language factors, whereas cross-language effects appear to be limited. An additional comparison of the bilingual data with a native control group showed that there are subtle but significant differences between L1 and L2 processing.

Testing a model for bilingual semantic priming with interlingual homographs: RT and N400 effects

Using a semantic priming paradigm, this study examines the effects of semantic and lexical-orthographic context on reaction times (RTs) and event-related potentials (ERPs) for interlingual homographs. Dutch-English bilinguals performed an English lexical decision task in which homographs like STEM (meaning voice in Dutch) were preceded by primes like ROOT or FOOL that were semantically related or unrelated to the English reading of the target word. Homographs were responded to faster following semantically related primes than following unrelated primes. The responses in both conditions were modulated by the relative frequencies of the two readings of the homographs: responses were faster when their English word frequency was high or when their Dutch word frequency was low. In the ERPs, N400 effects, taken to reflect processes of semantic integration, were found for homographs preceded by related primes. Remarkably, the amplitude of the N400 effect was also modulated by word frequency in both the first (Dutch, L1) and the second (English, L2) language. The observed relationship between lexical and semantic variables supports a model for bilingual semantic priming that extends the language nonselective BIA+ model for bilingual word recognition.

Testing the Language Mode Hypothesis Using Trilinguals

Current multilingual word recognition models differ in their account of non-linguistic context effects, for example effects due to stimulus list composition and task demands. Several models assume that the non-linguistic context can modulate the relative activation of words from different languages. One prominent example of such an approach is the Language Mode view by Grosjean (1997b), according to which the relative state of activation of a multilinguals two or more languages and language-processing mechanisms depends not only on the characteristics of the stimulus input, but also on situational characteristics. However, recent studies do not support this viewpoint. It predicts, for instance, that for Dutch–English bilinguals performing a purely Dutch word recognition task, English word candidates should not be activated. Nevertheless, under precisely those circumstances, Dutch–English and Dutch–French cognates (words with a similar orthography and meaning across languages) were both processed differently from Dutch control words by relatively proficient Dutch–English–French trilinguals. On the basis of this and other studies, we argue in favour of a stimulus-driven model for visual word recognition in which the non-linguistic context cannot affect the relative activation of word candidates from different languages.