Abstract

The featural and the categorical proposals of semantic memory organization were investigated through the use of a variant of the release from proactive interference (PI) paradigm. Six categories of verb concepts were employed: verbs similar in semantic and argument structure; verbs similar in argument, semantic and morphological structure; verbs similar in semantic content; verbs similar in argument and morphological structure and semantic content; and verbs similar in argument structure. As controls, three categories of nouns (e.g., fruits) were employed. Three main hypotheses were examined in three PI experiments conducted on healthy young adults: (1) If verb concepts were represented on the basis of semantic structure, then verb concepts sharing semantic structure were expected to generate the most substantial amount of build-up effect; (2) If concepts were represented on the basis of shared semantic content, then words sharing semantic content were expected to generate the most substantial amount of build-up effect; (3) Assuming that noun and verb concepts were encoded differentially, a significant magnitude of PI release was expected as a function of a shift from pre-shift trials to the shift trials.