A theory of sentence memory as part of a general theory of memory

We describe an ACT-R model for sentence memory that extracts both a parsed surface representation and a propositional representation. In addition, if possible for each sentence, pointers are added to a long-term memory refere nt which reflects past experience with the situation described in the sente nce, This system accounts for basic results in sentence memory without assu ming different retention functions for surface, propositional, or situation al information. There is better retention for gist than for surface informa tion because of the greater complexity of the surface representation and be cause of the greater practice of the referent for the sentence. This model' s only inference during sentence comprehension is to insert a pointer to an existing referent. Nonetheless, by this means it is capable of modeling ma ny effects attributed to inferential processing. The ACT-R architecture als o provides a mechanism for mixing the various memory strategies that partic ipants bring to bear in these experiments. (C) 2001 Academic Press.