We created the conditions necessary for cognitive representations to develop by presenting individuals and groups with word lists consisting of items high and low in associative strength. Strong cognitive representations were found to promote more schema-consistent memory errors than weaker representations. Moreover, strong cognitive representations resulted in more of these errors for groups than individuals. Weak cognitive representations, in contrast, resulted in fewer of these errors for groups than individuals. We find that variation in the frequency of memory errors between individuals and groups is influenced by the strength of shared representations that interfere with the ability of groups to correct schema-consistent memory errors among their members. Further analyses suggest that strong shared representations also aid correct recall relative to weak shared representations. We conclude that despite general advantages of collaboration, select circumstances that allow for strong shared representations may promote schema-consistent memory errors in groups.