In this paper, we present a formal approach to compositional processing of questions and answers in the Schizophrenia and Language, Analysis and Modeling corpus [1]. We address dialogue lexicality issues starting from the formal definitions of so-called Düsseldorf Frame Semantics given in [2]. We introduce a view of dialogues as compositions of negotiation phases that can be studied separately one from another while linked by a common dialogue context (accessible to all participants of a dialogue).