Young but not older adults adjust their criterion for the subjective vividness of memories according to task context

Rates of subjective recollection can change with participants’ expectations when they perform a memory task. In the current study, we examined whether young and older adults adjust their subjective vividness criterion according to their expectations in different memorability contexts. Young and older adults performed a memory task in which they memorized pictures varying in their level of memorability (low, medium or high), and each picture was associated with a descriptive label. At retrieval, from the labels, participants were asked to judge the vividness of their memories for the associated pictures. Retrieval blocks always started with labels of pictures of either low or high memorability, followed by labels of pictures of medium memorability. Thus, pictures of medium memorability were recollected in two memorability contexts, presumably associated with different levels of expectations. Results revealed that pictures of medium memorability were judged as more vivid by young adults when they were remembered after pictures of low than high memorability. However, this effect was not observed in older adults. These findings suggest that in young adults, the use of remembered picture details to frame a subjective sense of vividness is regulated by metacognitive mechanisms that take participants’ expectations into account. The finding that older participants’ vividness criterion was not sensitive to the memorability contexts suggests that the cognitive determinants of their subjective experience of remembering set the subjective vividness threshold in a different way relative to those of young individuals.