It is well established that access to the bilingual lexicon is non-selective: even in an entirely monolingual context, elements of the non-target language are active. Research has also shown that activation of the non-target language is greater at higher proficiency levels, suggesting that it may be proficiency that drives cross-language lexical activation. At the same time, the potential role of age of acquisition (AoA) in cross-language activation has gone largely unexplored, as most studies have either focused on adult L2 learners or have conflated AoA with L2 proficiency. The present study examines the roles of AoA and L2 proficiency in L2 lexical processing using the visual world paradigm. Participants were a group of early L1 Afrikaans–L2 English bilinguals (AoA 1–9 years) and a control group of L1 English speakers. Importantly, in the bilingual group, AoA and proficiency were not correlated. In the task, participants viewed a screen with four objects on it: a target object, a competitor object whose Afrikaans translation overlapped phonetically with the target object, and two unrelated distractor objects. The results show that the L2 English group was significantly more likely to look at the cross-language competitor than the L1 English group, thus providing evidence of cross-language activation. Importantly, the extent to which this activation occurred was modulated by both L2 proficiency and AoA. These findings suggest that while these two variables may have been confounded in previous research, they actually both exert effects on cross-language activation. The locus of this parallel activation effect is discussed in terms of connectionist models of bilingualism.

公认的是，对双语词典的访问是非选择性的：即使在完全单语的情况下，非目标语言的元素也处于活动状态。研究还表明，非目标语言的激活程度越高，表明跨语言词汇激活的能力越强。同时，由于大多数研究要么集中于成年的L2学习者，要么将AoA与L2熟练程度相结合，因此，尚无法探讨习得年龄（AoA）在跨语言激活中的潜在作用。本研究使用视觉世界范式检验了AoA和L2熟练度在L2词汇处理中的作用。参加者是一组早期的母语为L1南非荷兰语至L2的英语双语者（AoA为1至9岁）和一个由L1的英语为母语的对照组。重要的，在双语组中，AoA与熟练程度无关。在任务中，参与者查看了一个在屏幕上带有四个对象的屏幕：一个目标对象，一个南非荷兰语翻译与目标对象在语音上重叠的竞争对手对象以及两个无关的干扰对象。结果表明，英语二语组比英语二语组更可能看跨语言竞争者，从而提供了跨语言激活的证据。重要的是，激活的程度受L2水平和AoA的调节。这些发现表明，尽管这两个变量在先前的研究中可能已被混淆，但它们实际上都对跨语言激活产生影响。根据双语主义的联系主义模型讨论了这种平行激活效应的源头。