This paper focuses on the modelling of the linguistic level of MICRO, a multi-agents speech understanding system largely inspired by cognitive models. It describes the cooperation between, on the one hand a syntactic parser using a Lexical Functional Grammar, and on the other hand an semantic analyser. The semantic analysis is achieved through a mechanism semantic priming carried out by a incremental associative network. We emphasize the adaptive abilities of such a cooperation, particularly in case of ungrammatical utterances, which are very common in spoken language.