Information flow

In discourse-based grammatical theory, information flow is any tracking of referential information by speakers. Information may be new, just introduced into the conversation; given, already active in the speakers' consciousness; or old, no longer active. The various types of activation, and how these are defined, are model-dependent.
Information flow affects grammatical structures such as

word order (topic, focus, and afterthought constructions).
active, passive, or middle voice.
choice of deixis, such as articles; "medial" deictics such as Spanish ese and Japanese sore are generally determined by the familiarity of a referent rather than by physical distance[citation needed].
overtness of information, such as whether an argument of a verb is indicated by a lexical noun phrase, a pronoun, or not mentioned at all.

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