Modeling lexical effects in language production: where have we gone wrong?

Words have their own conceptual representations, semantic properties, and physical forms. These lexical characteristics not only set words apart as a distinct item in the lexical repertoire but also provide valuable insight into the processes and mechanisms of language production. Over the past decades there has been a large body of research examining how word meaning, form, and usage directly affect the speed of monolingual speakers’ production (e.g. Alario et al., 2004; Barry, Morrison, & Ellis, 1997; Bates et al., 2003; Bonin, Chalard, Méot, & Fayol, 2002). Of note, almost all these studies have failed to accommodate the fact that word usage, given it is a behavioral outcome (Zevin & Seidenberg, 2002, 2004), likely mediates the relationship between meaning/form and spoken production. Moreover, lexical characteristics have been predominantly examined as discrete variables in the literature, but in fact, some of them may correspond to the same layer of language production or the same aspect of lexical knowledge. Additionally, little work has been done on children’s emerging bilingual lexical representations, especially those learning an L2 within input-limited contexts, possibly due to the fact that this population has only recently begun to receive focused attention in the research field. In order to delineate the exact manner in which lexical effects come into play, the present study used structural equation modeling to perform a simultaneous test of the complex relationships among a variety of lexical variables and to assess their direct, indirect and total effects on L2 lexical processing efficiency. Furthermore, attempts were also made to estimate and then to compare three types of hypothesized models, in which the lexical relationships were specified differently with respect to spoken production in L2 learners. 2 Lexical characteristics that contribute to the speed of spoken production