In this dissertation, I address two outstanding questions regarding how linguistic and extra-linguistic information are brought together in the interpretation of language situated within a discourse. The first part of this dissertation experimentally addresses how alternatives invoked by sentences containing the focus-sensitive operator 'only' are…

Problems related to the structure of the mental lexicon are considered. The single access assumption, the passive memory assumption, and the heterogeneous memory assumption are rejected in favor of the theory which assumes several active memories, each able to store expression based on only one homogenous set of abstract primitives. One lexicon…

Presents an algorithm for use in natural language document retrieval systems which automatically determines if the conjunction "and" in a statement representing an information need should be translated into a Boolean "and" or "or." The results of an experiment that used the algorithm are reported, and further research is suggested. (CLB)

Describes a system developed for the automatic recognition of biological concepts in titles of scientific articles; reports results of several pilot experiments which tested the system's performance; analyzes typical ambiguity problems encountered by the system; describes a disambiguation technique that was developed; and discusses future plans…