This paper describes a method to construct from a set of documents a spatial representation that can be used for information retrieval and knowledge discovery. The proposed method has been implemented in a prototype system and allows the researcher to browse interactively and in real-time a network of relationships obtained from a set of full text articles. These relationships are combined with the potential relationships between concepts as defined in the UMLS semantic network. The browser allows the user to select a seed term and find all related concepts, to find a path between concepts (hypothesis testing), and to retrieve the references to documents or database entries that support the relationship between concepts.