High-frequency words are processed faster than low-frequency words, known as the word frequency effect (FE). Although the FE has been studied in various writing systems as well as in first- (L1) and second-language (L2) reading, existing theoretical hypotheses are mainly based on findings in alphabetic languages. To date, no study has investigated theoretical explanations of the FE such as the learning hypothesis, the lexical entrenchment hypothesis and the rank hypothesis apply to Chinese–English bilinguals. The present study, therefore, compared the FEs in Chinese– and Dutch–English bilinguals during natural paragraph reading in their L1 and L2, using eye-tracking measures. Chinese bilinguals exhibited a larger FE in L2 than in L1. They displayed smaller L1 FEs and much steeper L2 FE curves than Dutch bilinguals. These findings are not entirely consistent with the existing FE hypotheses, and the present study discusses theoretical accounts in light of the observed results.

Previous research identified that studying texts in a second language (L2) as opposed to the first (L1) results in substantially weaker recall. We hypothesized that use of advance organizers (AOs) might attenuate this L2 recall cost by supporting L2 users in the construction of more solid memory representations. One hundred Dutch-English bilinguals studied two texts in either L1 or L2, and with or without the help of a mind map. The previously reported L2 cost was replicated, with lower recall scores in L2 relative to L1. Whereas L1 and L2 students were equally aided by AO use, the initial cost dissipated when comparing L2 test scores in the AO condition with those of L1 in the non-AO condition. We therefore conclude that employing AOs does not entirely diminish L2 disadvantages but brings L2 students up to the initial level of L1 students.

Research among bilinguals suggests a foreign language effect for various tasks requiring a more systematic processing style. For instance, bilinguals seem less prone to heuristic reasoning when solving problem statements in their foreign (FL) as opposed to their native (NL) language. The present study aimed to determine whether such an effect might also be observed in the detection of semantic anomalies. Participants were presented NL and FL questions with and without anomalies while their eye movements were recorded. Overall, they failed to detect the anomaly in more than half of the trials. Furthermore, more illusions occurred for questions presented in the FL, indicating an FL disadvantage. Additionally, eye movement analyses suggested that reading patterns for anomalies are predominantly similar across languages. Our results therefore substantiate theories suggesting that FL use induces cognitive load, causing increased susceptibility to illusions due to partial semantic processing.

Language switching experience is assumed to have an effect on domain-general control abilities in bilinguals, but previous studies on the relationship between these two variables have generated mixed results. The present study investigated the effects of bilingual experiences on the interaction between language switching and domain-general control. Thirty-two Dutch–French bilingual young adults executed a bilingual categorisation task to assess their language switching abilities and a Simon task to assess domain-general control. The results show that global response times on the Simon task were correlated to the forward switch cost (from L1 to L2); moreover, interestingly, the forward switch cost was found to be related to recent language exposure but not to the age of second language acquisition. We suggest a monitoring account of language switching to integrate the first finding with previous studies and we interpret the second finding as support for the adaptive control hypothesis.

Despite an increase in bilingualism and the use of English as a medium of instruction, little research has been done on bilingual memory for learnt information. In a previous study, we found an L2 recall cost but equal recognition performance in L2 versus L1 when students studied short expository texts (Vander Beken & Brysbaert, 2017). In this paper, we investigate whether there is a recognition cost after a longer delay, which would indicate that the memory trace is weaker in L2. Results showed equal performance in L1 and L2, suggesting that the recall cost is either located at the production level, or that the levels-of-processing effect is mediated by language, with unaffected surface encoding leading to effective marginal knowledge on the one hand, and hampered deep encoding leading to ineffective (uncued) recall. This paper also contains the Dutch vocabulary test we used for native speakers.

In an ongoing debate, bilingual research currently discusses whether bilingualism enhances non-linguistic executive control. The goal of this study was to investigate the influence of language-switching experience, rather than language proficiency, on this bilingual executive control advantage. We compared the performance of unbalanced bilinguals, balanced non-switching, and balanced switching bilinguals on two executive control tasks, i.e. a flanker and a Simon task. We found that the balanced switching bilinguals outperformed both other groups in terms of executive control performance, whereas the unbalanced and balanced non-switching bilinguals did not differ. These findings indicate that language-switching experience, rather than high second-language proficiency, is the key determinant of the bilingual advantage in cognitive control processes related to interference resolution.

The current study investigated the effects of bilingualism on the clinical manifestation of Alzheimer's disease (AD) in a European sample of patients. We assessed all incoming AD patients in two university hospitals within a specified timeframe. Sixty-nine monolinguals and 65 bilinguals diagnosed with probable AD were compared for time of clinical AD manifestation and diagnosis. The influence of other potentially interacting variables was also examined. Results indicated a significant delay for bilinguals of 4.6 years in manifestation and 4.8 years in diagnosis. Our study therefore strengthens the claim that bilingualism contributes to cognitive reserve and postpones the symptoms of dementia.