A new study finds that being distracted while recalling information makes it harder to perform other tasks concurrently, especially for older adults--a finding that might help older adults learn how to remember things but also shows that their cognitive capacity could be limited to handling one task at a time.
To reach this conclusion, Moshe Naveh-Benjamin, PhD, of the University of Missouri-Columbia, Fergus Craik, PhD, of the Rotman Research Institute in Toronto, and colleagues tested 64 University of Toronto undergraduates and 64 Toronto residents averaging 70 years old on a word recall task. The test used 12 lists of 12 word pairs--six lists with related word pairs (for example, waiter-kitchen) and six with unrelated pairs (paper-apple). Participants studied each pair for six seconds then recalled each word when researchers presented its mate.
Before studying the lists, half of the participants received instructions to memorize the word pairs. The other half were told, in addition, to learn the pairs by employing a strategy that related the two words, such as by forming a mental image of the two words interacting or thinking of a sentence that included the two words.
Participants also undertook a tracking task, in which they used a mouse to follow as closely as possible a green asterisk moving across a computer screen. Some participants performed the tracking task while they learned the words, while others performed the tracking task only during recall.
The researchers found that while younger adults performed better than their older counterparts, members of both groups who learned word pairs while their attention was divided performed much worse when recalling the words.
For those whose attention was divided during recall, performance wasn't affected much. However, these participants' performance on the tracking task was much worse--especially among the older participants. Why? Because retrieving information while doing something else requires expending more cognitive resources than older adults might have, Naveh-Benjamin suggests.
"For example, if you ask older adults for instructions on how to get someplace, it might affect their behavior on other tasks," he says. "If they are driving, you don't want to ask them too many questions."
Notably, mentally relating word pairs helped old and young participants equally. The strategy can benefit older adults in many practical ways, Naveh-Benjamin says--for example, they can relate two ingredients to help them better recall a recipe, he says--but it demands more effort from them.
"Older adults can use that strategy to, say, relate different aspects of an address or phone number they must learn," he says. "It can really help their memory, but whatever else they are doing at the time might suffer."
The findings appear in APA's Journal of Experimental Psychology: Learning, Memory and Cognition (Vol. 31, No. 3).