This study compared patterns of nonselective cross-language activation in L1 and L2 visual word recognition with different-script bilinguals. The aim was to determine (1) whether lexical processing is nonselective in the L1 (as in L2), and (2) if the same cross-linguistic factors affected processing similarly in each language. To examine the time course of activation, eye movements were tracked during lexical decision. Thirty-two Japanese–English bilinguals responded to 250 target words in Japanese and in English. The same participants and items (i.e., cognate translation equivalents) were used to directly compare L1 and L2 processing. Response latencies as well as eye movements representing early and late processing were analyzed using mixed-effects regression modeling. Similar cross-linguistic effects, namely cognate word frequency, phonological similarity, and semantic similarity, were found in both languages. These factors affected processing to different degrees in each language, however. While cognate frequency was significant as early as the first fixation, effects of cross-linguistic phonological and semantic similarity arose later in time. Increased phonological similarity slowed responses in L2 but speeded them in L1, while greater semantic overlap was facilitatory in both languages. Results are discussed from the perspective of the BIA+ model of visual word recognition.

The current study examined automatic activation and semantic influences from the non-target language of different-script bilinguals during visual word processing. Thirty-four Arabic–Hebrew bilinguals and 34 native Hebrew controls performed a semantic relatedness task on visually presented Hebrew word pairs. In one type of critical trials, cognate primes between Arabic and Hebrew preceded related Hebrew target words. In a second type, false-cognate primes preceded Hebrew targets related to the Arabic meaning (but not the Hebrew meaning) of the false-cognate. Although Hebrew orthography is a fully reliable cue of language membership, facilitation on cognate trials and interference on false-cognate trials were observed for Arabic–Hebrew bilinguals. The activation of the non-target language was sufficient to influence participants’ semantic decisions in the target language, demonstrating simultaneous activation of both languages even for different-script bilinguals in a single language context. To discuss the findings we refine existing models of bilingual processing to accommodate different-script bilinguals.