Lexical Associations in a Native and Non-Native Language Affect Retrieval-Induced Forgetting

Recent work suggests that speakers' lexical networks in their native and secondary languages are organized somewhat differently, with native languages showing greater systematicity. We here test this claim in a new way, by making use of the “Retrieval-induced forgetting” effect (RIF). Specifically, practicing previously encoded information through rehearsal is expected to result in better memory for that information, regardless of which language the information is encoded. The RIF effect involves the suppression of information that is associated with the practiced information but is itself unpracticed. Since RIF is understood to rely on the association between the practiced and unpracticed memories, we predict it will be weaker when applied in a language with weaker or less systematically organized lexical associations. Results confirm that while the expected practice effect was evident in participants' native and second languages, the RIF effect was only significant in participants' native language. We discuss the relevance and implications of this finding for second language speakers.