Switching Between Taxonomic and Thematic Semantic Processing

The present project had two distinct goals. One was to develop and provide a large set of normed materials of taxonomic and thematic word pairs for future studies to utilize. The second goal of the present project was to test predictions about the underlying mechanisms responsible for taxonomic and thematic semantic processing made by the distributed plus-hub and dual-hub theories of semantic memory. This was done using triads and oddball semantic judgment tasks to test for a taxonomic-thematic switch cost. The presence of a switch cost would fall in line with the dual-hub theory where it is posited that taxonomic and thematic semantics are processed independently and therefore when switching between the judgments a behavioral or in the case of the present studies a reaction time cost would appear. The results of the triads and oddball switch cost studies fall in line with the dual-hub theory of semantics, as regardless of the direction of the switch (i.e. taxonomic to thematic or thematic to taxonomic) reaction times were slower when compared to making sequential judgments of the same type.