Implicit memory is vulnerable to proactive interference

We investigated the possibility that implicit memory, like explicit memory, can be disrupted by proactive interference. Participants first viewed a li st of words, with nontargets in the first half of the list and targets in t he second. Nontargets were either similar in structure (e.g., "ANALOGY") or unrelated (e.g., "URGENCY") to the targets (e.g., "ALLERGY"). After severa l filler tasks, participants completed an implicit fragment-completion test (e.g., "A_L__GY") for the target items. Participants who viewed similar no ntargets completed fewer fragments with target items and made more intrusio ns than did participants who viewed unrelated nontargets. Together with pre vious findings, these results suggest that similar nontargets can compete w ith target items to produce interference in implicit memory.