This dissertation investigates how grammatical functions in transitive sentences (i.e., `subject' and `direct object') are distributed in written Swedish discourse with respect to morphosyntactic as well as semantic and referential (i.e., prominence-based) information. It also investigates how assignment of grammatical functions during on-line comprehension of transitive sentences in Swedish is influenced by interactions between morphosyntactic and prominence-based information. In the dissertation, grammatical functions are assumed to express role-semantic (e.g., Actor and Undergoer) and discourse-pragmatic (e.g., Topic and Focus) functions of NP arguments. Grammatical functions correlate with prominence-based information that is associated with these functions (e.g., animacy and definiteness). Because of these correlations, both prominence-based and morphosyntactic information are assumed to serve as argument interpretation cues during on-line comprehension. These cues are utilized in a probabilistic fashion. The weightings, interplay and availability of them are reflected in their distribution in language use, as shown in corpus data. The dissertation investigates these assumptions by using various methods in a triangulating fashion. The first contribution of the dissertation is an ERP (event-related brain potentials) experiment that investigates the ERP response to grammatical function reanalysis, i.e., a revision of a tentative grammatical function assignment, during on-line comprehension of transitive sentences. Grammatical function reanalysis engenders a response that correlates with the (re-)assignment of thematic roles to the NP arguments. This suggests that the comprehension of grammatical functions involves assigning role-semantic functions to the NPs. The second contribution is a corpus study that investigates the distribution of prominence-based, verb-semantic and morphosyntactic features in transitive sentences in written discourse. The study finds that overt morphosyntactic information about grammatical functions is used more frequently when the grammatical functions cannot be determined on the basis of word order or animacy. This suggests that writers are inclined to accommodate the understanding of their recipients by more often providing formal markers of grammatical functions in potentially ambiguous sentences. The study also finds that prominence features and their interactions with verb-semantic features are systematically distributed across grammatical functions and therefore can predict these functions with a high degree of confidence. The third contribution consists of three computational models of incremental grammatical function assignment. These models are based upon the distribution of argument interpretation cues in written discourse. They predict processing difficulties during grammatical function assignment in terms of on-line change in the expectation of different grammatical function assignments over the presentation of sentence constituents. The most prominent model predictions are qualitatively consistent with reading times in a self-paced reading experiment of Swedish transitive sentences. These findings indicate that grammatical function assignment draws upon statistical regularities in the distribution of morphosyntactic and prominence-based information in language use. Processing difficulties in the comprehension of Swedish transitive sentences can therefore be predicted on the basis of corpus distributions.

In my Ph.D. thesis, I examine the use of referential devices in spoken narrative discourse with predominant anaphoric reference. Special attention is paid to the relationship between two competing forms: lexical phrases containing the lexeme ten (ten-MARKED NPs) and lexical phrases not containing it (UNMARKED NPs) in repeated mentions. A primary aim of the work is (i) to identify factors favouring the use of ten-marked NPs at the expense of unmarked NPs and (ii) to explore the possibility of the lexeme ten grammaticalizing from its anaphoric use. Theoretically and methodologically I benefit mostly from the conception of discourse anaphora and the theory of grammaticalization. The referential devices are systematically explored in terms of their distribution into different classes according to a set of parameters and their values. These parameters reflect the conceptual (animacy), grammatical (syntactic function, type of clause etc.) as well as discourse characteristics of the forms and their referents (informational status of the NP in the clause, activation and persistence of the referent, etc.). The data consist of 45 short narratives produced by 15 speakers. The speakers' task was to retell three short silent-movie sketches which they had seen immediately before the recording. The design of the...