A memory-interference versus the "dud"-effect account of a DRM false memory result: Fewer related targets at test, higher critical-lure false recognition.

Memory interference theories hold that exposure to more similar information to a target item impairs memory of the target item. The dud effect refers to the finding in eyewitness lineup identification that fillers dissimilar to the suspect cause more false identification of the suspect than similar fillers, contrary to the interference concept. Previous studies on the Deese-Roediger-McDermott false memory typically showed a testing priming effect that a larger number of studied items presented at test leads to a higher level of false recognition of the critical lure (CL). In the present study, either all, or all but one studied item were replaced by unrelated distractors at test. Subjects made more false recognitions of the CL in the no- or only-one-studied item than in the multiple-studied-item condition, supporting the dud-effect account. The slower response time in the "dud" condition suggested a deliberate, monitoring-like approach taken by subjects in that condition.