When more is less: The effect of a third language on a second language

Previous research (Van Heste, 1999; Van Hell & De Groot, 1998; Van Heuven, Dijstra & Grainger, 1998) has shown word comprehension behaves in a non-selective fashion and that bilinguals show sensitivity to one language's word features during word processing in another language. The majority of the previous studies have focused on investigating how lexical processing occurs among bilinguals. The present study, explores how trilinguals process words in comparison to bilinguals. In addition it focuses on observing how trilinguals process words in typological similar languages such as Spanish and Portuguese.;In this study, a group of bilingual speakers (n=54) (First Language (L1) English and Second Language (L2) Spanish) and a group of trilingual speakers (n=66) (L1 English/Spanish, L2 Spanish/English, L3 Portuguese) completed a lexical decision task in Spanish. The stimuli in the experiment were manipulated to appear similar to words in various languages. The logic was to test whether the presence of a third language would affect processing in a second language. Participants were exposed to real and pseudo words in 8 different categories divided by 4 languages (Spanish, Portuguese, German and Basque) and their task was to decide whether the words presented were real Spanish words. Reaction times and accuracy were analyzed among both groups and across word type.;It was predicted that trilingual participants would show sensitivity to words in Spanish and Portuguese (real and pseudo words) and would present longer reaction times and less accurate results to process words in Portuguese or resembling Portuguese because of the parallel activation of the L3. The results do indicate that the activation of Portuguese affected trilinguals ability to judge words in Spanish. Moreover, the additional language activation of Portuguese affected trilinguals' ability to simply accept words in Spanish as real words. In other words, the L3 affected the L2 in a detrimental way. Additional analysis investigating language learning factors (such as heritage speaker status and polyglot status) shed some light on the complexity of the L3 effect present in the trilinguals. The present findings are analyzed in light of Van Heuven and Dijkstra's (1998) model of Bilingual word recognition (BIA).