Distinctive processing in young and older adults: Metacognitive judgments and the isolation paradigm

The isolation paradigm is often used for studying the effects of distinctiveness on memory. Within this paradigm the isolated item can appear early or late in the list. Most prior studies using the isolation paradigm with older adults placed the isolated items late in the study list, however, Smith (2011) used an early isolation list and found that older adults showed an early isolation effect when the dimension of isolation was more readily detected (numbers vs. letters) but did not show an isolation effect when the dimension of difference was more subtle (category membership). The current experiments replicate these findings and demonstrate judgments of learning are elevated for the isolated item in the former case, but not in the latter case, for young and older adults.