Abstract

Decisions are often based on memory, but memories are often vague and ambiguous. Therefore, one must establish some standard for how strong a memory must feel before it is accepted as part of one’s past. This standard of evidence, called a decision criterion, should be adapted to the demands of a given situation: Sometimes it is critical to accept only strong memories as legitimate, whereas at other times it is more appropriate to act on the basis of relatively weak memory evidence. The ability to shift between these two standards as circumstances warrant is a critical element of successful decision making. We review recent work examining criterion shifting in recognition memory and argue that the true nature of criterion shifting may be seen only at the individual level: Whereas some people shift their criterion quite adaptively, others do not shift at all.