The role of discourse markers in the generation and interpretation of discourse structure and coherence

The present paper studies the notions of turn management and topic orientation, and more specifically, a group of pragmatic elements, so-called discourse markers (DMs) which indicate the act of next speaker selection, turn-keeping, topic elaboration and digression. After definitions of discourse marker, turn, floor control types/turn segments, topical units and actions are provided, a list of verbal and nonverbal discourse markers will be given, and they will be grouped into subclasses on the basis of the meaning relations between the linked discourse segments and the type of floor control and thematic control affected. The fundamental question is if discourse markers are key indicators of discourse structure and can be used in the automatic interpretation of utterance meaning and rhetoric relations. The goal of the paper is twofold: firstly, to identify how nonverbal behavior (gestures, posture, gaze) may help disambiguate the actual function(s) of a discourse marker in a given context; secondly, to make explicit how different modalities work together in a synchronized manner in turn regulation and topic control during cooperative interaction. It is examined in twenty spontaneous dialogues of the Hungarian HuComTech multimodal corpus what roles and functions verbal and nonverbal discourse markers play in indicating discourse structure and coherence relations. Concordances and corpus queries presented address both the verbal and nonverbal features of different turn management behavior and topical actions accompanied or supported by discourse markers. Taking a semasiological approach, some of the controversial defining features of discourse markers generally listed in the literature will be tested on a few Hungarian discourse markers: hát (‘well’), tehát (‘so’), mondjuk (‘say’), amúgy (‘otherwise’), egyébként (‘by the way’), szerintem (‘I t- ink’). The features in question regard their position (turn-initiality, topic unit-initiality) as well as the genre-specificity and gender-specificity of their use.