Finally, Chapter 11 is concerned with alternating pairs of constructions, such as active and passive clauses and singular and plural nouns, which are commonly analyzed as paradigmatic alternatives of particular grammatical categories such as voice and number. Crucially, paradigmatic alternatives of this type are often asymmetrical in the sense that the less frequent member of an alternating pair of constructions is marked by an extra morpheme (e.g., a voice or number marker). Linguistic typologists refer to this asymmetry by the notion of markedness and have argued that frequency accounts for the occurrence of the extra marker. Chapter 11 presents a network analysis of the encoding asymmetries of grammatical categories based on research from typology and psycholinguistics. While the proposed account applies to a large number of categories (e.g., voice, number, tense, aspect, case), the chapter is primarily concerned with a phenomenon known as differential object marking, which has played a key role in recent typological and psycholinguistic research on grammatical relations.

Every construction has a particular ecological location in the grammar network that is defined by its relationship to other constructions in the system. Since the relationships between constructions are similar to those between lexemes, Chapter 10 begins with a short discussion of psycholinguistic research on the mental lexicon, which is commonly analyzed as an activation network (Dell 1986). There is abundant evidence that lexical access is influenced by several interacting factors including frequency, priming, similarity and neighborhood density, or family size. Considering research on sentences processing, L1 acquisition and language change, the chapter argues that the availability, or accessibility, of constructions is influenced by the same factors as lexical access, that is, by frequency, priming, similarity and neighborhood density, supporting the hypothesis that lexemes and constructions are organized in similar ways. Specifically, the chapter argues that grammar includes “construction families” that influence the use and the development of syntactic patterns (Diessel and Tomasello 2005; Wells et al. 2009).