Age differences in susceptibility to memory interference during recall of categorizable but not unrelated word lists

The authors examined how divided attention (DA) and aging affect memory, and the use of organizational strategies, during retrieval. Younger and older adults studied a list of either unrelated or categorizable words presented auditorily under full attention, and later recalled them under full attention or DA condition with a word- or digit-monitoring distracting task. The magnitude of memory interference did not interact with age during retrieval of unrelated words. During retrieval of categorizable words, older adults suffered significantly greater memory interference than young in both DA conditions. The number of categories recalled was significantly reduced by the word- but not digit-based distracting task, and this effect did not differ across age groups. The number of words recalled per category was reduced in both DA conditions, in both age groups. Semantic clustering, corrected for total recall score, was reduced in older but not younger adults, in both DA conditions. Findings suggest that older adults cannot make use of strategies, to the same extent as do young, to boost memory for categorized words under DA conditions, leading to amplified memory interference.