'Weak' memories make strong comeback.

Weak' Memories Make Strong Comeback

A widely accepted psychological theory holds that when people try to recall several items, they remember first those items that initially gained a strong foothold in their memories. But this commonsense contention is wrong, says psychologist Charles J. Brainerd of the University of Arizona in Tucson.

By as early as age 6, people who are asked to recall lists of items from memory tests--in any order that springs to mind--first mention items that they previously had the most trouble recalling, Brainerd and his colleagues report in the July PSYCHOLOGICAL SCIENCE. The researchers dub this the "cognitive triage" effect--an analogy to the medical procedure of triage, in which physicians treat the most difficult cases first.

"Deliberate mnemonic strategies are important in memory development, but they're by-products of basic, unconscious memory processes such as cognitive triage," Brainerd argues.

If cognitive triage holds up in further studies, it could have numerous practical implications, he adds. For instance, rather than answering items one after the other on school examinations, students might maximize their recall by scanning the items and attempting the hardest questions first. Moreover, police and lawyers interrogating children who have witnessed crimes might obtain more information by posing questions about critical and disturbing events first, rather than starting out with queries designed to put the youngster at ease.

"Brainerd's data are very compelling," remarks psychologist Stephen J. Ceci of Cornell University. "But it's hard to say if his controlled laboratory findings will generalize to emotionally charged situations such as eyewitness testimony."

While the findings provide hope for improving recollections of child eyewitnesses, Ceci says, young children often store memories in bits and pieces that cannot be reassembled through any retrieval tactic.

Brainerd and his co-workers conducted 11 memory experiments with youngsters between the ages of 6 and 13. The number of participants in each experiment ranged from 50 to 96. Investigators presented each child with a list of 12 to 24 items, such as nouns or simple pictures, and then asked them to perform a brief activity, such as counting backwards, to empty short-term memory. Afterward, children reported all the items they remembered. The youngsters repeated this memory recall procedure up to five times consecutively for the same list of items.

In several experiments, researchers allowed children as many trials as needed to recall all the items on a list. Two weeks later, they administered five consecutive recall tests to reassess the children's memory for the items.

On each subsequent memory trial in all the experiments, children first recalled several "weak" items -- those remembered least often in previous trials -- followed by "strong" items most often recalled in earlier tests, and finally some more weak items.

The same memory pattern -- weak items, then strong items, then weak items again -- appeared when the scientists reanalyzed responses on recall tests taken by more than 2,000 adults in several previously reported experiments.

Researchers usually do not track weakly and strongly recalled items across memory trials because they assume stronger items emerge first, Brainerd says.

In 1965, however, scientists reported cognitive triage among adults, notes psychologist Robert G. Crowder of Yale University. The authors of that controversial study suggested adults use conscious strategies to focus on items that have previously given them trouble.

But the new evidence of cognitive triage among children as young as 6 suggests weakly recalled items gain an unconscious memory edge, Brainerd contends. Since each item recalled generates associations to other information in memory storage, which in turn interfere with further recall, Crowder speculates that cognitive triage may be an "unconscious, adaptive strategy" for getting weakly remembered items to surface first.