This article concerns the controversial issue of bilingual speech production, and the differing models of how the activation of lexical nodes is spread to the corresponding phonological representations.

The following questions are discussed: (1) whether the phonological segments of the nonresponse language of a bilingual person are activated by the target word and semantically related lexical items, and (2) whether the activated phonological segments of the nonresponse language in their turn affect the retrieval of the phonological representations of the target word. As will be shown in the literature review, there is experimental evidence that provides support for both questions. However, further research and new experimental paradigms are needed to fully understand the processes involved in bilingual language production that would allow us to draw substantive conclusions about the architecture of the speech production mechanisms.

This issue is of great importance and interest for those who are concerned with the psychology of bilingualism and multilingualism. The understanding of the processes of language production that are related to bilingual speakers of different age groups and levels of proficiency may shed light on general issues of L1 and L2 acquisition. In addition, the knowledge of L1 and L2 development can have practical application for language instruction.

In the present article, first the background information on the processes/models of language production is presented; then two highly debated hypotheses of discrete and cascaded models are discussed.  A big portion of this article is devoted to the experimental evidence that supports either of the models. Finally, the experimental paradigms are analyzed which provides new ideas for further research in this area.