The present study aims at exploring: (a) the role of the educational setting in the acquisition of aspect and executive functions (i.e. updating) skills, (b) the acquisition of the aspectual features in Greek-German bilingual children and (c) the impact of updating on the acquisition of aspect. Imperfective aspect has been found to be acquired later than perfective in previous studies. Moreover, a bilingual educational setting seems to enhance not only cognitive but also linguistic abilities. The participants of the present study are Greek-German bilingual children, who attend a bilingual or a Greek dominant educational setting. They were tested in two baseline tasks, two linguistic tasks and an executive function, updating, task. The findings reveal that bilinguals who attend a monolingual educational setting performed similarly to the monolingual control group on aspect, whereas bilinguals who attend a bilingual educational setting scored lower than the monolinguals. In the updating task, the students of the bilingual educational setting scored higher than the other groups. Overall, our findings suggest that the bilingual educational setting seems to boost executive function (updating) skills, while the acquisition of aspect is affected by vocabulary knowledge.

The present study explores the effects of literacy support in the languages of the bilingual child on the linguistic and cognitive skills of (non-)heritage speakers. 70 children speaking Albanian (L1) and Greek (L2) are divided into three groups according to whether they receive literacy support in their L1, L2 or in both languages. To test the children's proficiency in Greek, we used an expressive vocabulary task, two working memory tasks, a non-verbal intelligence task and a sentence repetition task (SRT). The findings suggest that good levels of biliteracy established through bilingual education positively influence the child’s linguistic and cognitive performance. Furthermore, the lack of working memory effects on the children’s SRT performance emphasizes the importance of biliteracy development and its educational support, which together with vocabulary knowledge contribute to bilingual development.

The current study investigated the depth of vocabulary knowledge (VK) through word definitions, examining the effect of word characteristics, breadth of VK, and verbal working memory (VWM). Forty children (11-12 years old) participated (12 Greek-Albanian children Greek-dominant, 14 Turkish-Greek children Turkish-dominant, and 14 monolinguals). An expressive vocabulary task (breadth of VK), a word definition task (depth of VK) in Greek, and a VWM task were administered. The results revealed that monolinguals had larger vocabulary than bilinguals in Greek. Greek-Albanian children had also larger vocabulary than Turkish-Greek bilinguals. In the VWM task, monolinguals had better abilities than Turkish-Greek bilinguals. Controlling for vocabulary and VWM, few differences emerged in definitional skills. In simple concrete nouns and compound verbs, Greek-Albanian children gave more formal definitions than monolingual children, exhibiting a bilingual advantage. Finally, breadth and depth of VK correlated with VWM only in Greek-Albanian and monolingual children, indicating the impact of vocabulary on VWM performance.

Definitions exhibit aspects of mental lexicon organization. Learners with Developmental Language Disorder (DLD) have limited vocabulary knowledge (in breadth and depth) and, thus, less mature definitional skills. Word characteristics affect the definitional skills. This study investigated the definitional skills of learners with and without DLD considering different word characteristics. Moreover, issues like deviant vs. delayed abilities and the link between breadth and depth of vocabulary knowledge are addressed. Thirty-six learners were divided into three groups (a DLD and two control groups [CG] of typically developing learners matched on either age or vocabulary). They were asked to define 16 words. Answers were scored for content and form. Findings revealed that the DLD group scored lower than both CGs in content, while no differences were found in form. Definitions of abstract and compound words were more demanding for all. Correlations between vocabulary and definitional skills were detected only in the age-matched CG. From the above, we deduce that DLD learners’ definitional skills are deviant. In addition, clinical practice should not look at effects of isolated variables, but rather investigate the interrelation of different parameters. Finally, the link between breadth and depth of vocabulary knowledge may require more time to emerge in DLD learners.