The effects of repeated idea elaboration on unconscious plagiarism.

Unconscious plagiarism occurs in a recall task when someone presents someone else's idea as his or her own. Recent research has shown that the likelihood of such an error is inflated if the idea is improved during the retention interval, but not if it is imagined. Here, we explore the effects of repeating the elaboration phase during the retention interval. Participants in a group first generated alternate uses to common objects before elaborating the ideas either by imagining them or by improving them. This elaboration phase occurred once, twice, or not at all. Later, they attempted to recall their original ideas and generate new ideas. Repeated imagery did not inflate unconscious plagiarism on either task. In contrast, repeating the improvement phase increased plagiarism to dramatically high levels in the recall task. The latter effect might be particularly pertinent to real-world cases of plagiarism in which the ideas under dispute have been the subject of creative development over many occasions.