A theoretical construct developed by George Lakoff in order to account for the typicality effects uncovered by prototype theory. An ICM is a relatively stable mental representation that represents a ‘theory’ about some aspect of the world and to which words and other linguistic units can be relativized. In this respect, ICMs are similar to the notion of a frame, since both relate to relatively complex knowledge structures. However, while ICMs are rich in detail, they are ‘idealized’ because they abstract across a range of experiences rather than representing specific instances of a given experience. For instance, the lexical concept (bachelor) is understood with respect to a marriage ICM which includes schematic information relating a marriage age, a marriage ceremony, the social, legal, religious and moral dimensions and responsibilities associated with marriage, the participants involved in marriage and the conditions governing their status before and after the event of the marriage ceremony, different events associated with the trajectory of marriage, including the marriage ceremony itself, venues for performing the marriage ceremony, and so forth. According to Lakoff, ICMs are employed in cognitive processes such as categorization and reasoning. As ICMs constitute coherent bodies of knowledge representation, the way they are structured is organized in various ways. These include being organized by virtue of the image schema, metaphor and metonymy. ICMs are also employed in order to structure mental space s during on-line meaning construction.

This is achieved via a process known as schema induction.