A U of T study shows that the same brain dysfunction that leads to memory impairment in older adults might actually contribute to their ability to make wiser everyday decisions.
“As we get older, our ability to ignore distractions gets worse. Often that leads to memory problems, but this study showed that it is also advantageous,” says Karen Campbell, co-author of a research article on “hyper-binding” published in Psychological Science in January.
Hyper-binding is what happens when an aged brain makes “overly broad associations” between events that happen close to one another. It is caused by a brain dysfunction that hinders the mind’s ability to memorize only relevant details. But as this study showed, relevance is subjective. The details that you don’t want to focus your attention on in the present can actually help you in the future.
“Older adults pick up on more subtle causes and effects, giving them more knowledge of how things go together. And the more stuff you do pick up on might lead to the ability to make better decisions,” says Campbell. “Say you’re in a workplace and trying to make a decision about who you’re going to promote. If you’re only focused on somebody’s work performance, you might not notice other things about their character […] that could help you make a more informed decision.”
The Experiments
The authors of “Hyper-Binding: A Unique Age Effect,” published in the journal Psychological Science in January, drew this remarkable conclusion from two related experiments that studied 44 young adults (with an average age of 19) and 44 older adults (with an average age of 67).
In both studies, participants observed a series of pictures on a computer screen and were asked to press the spacebar every time they saw the same picture twice in a row. But there was a twist. Each picture had a word superimposed on top. Participants were told to ignore the distracting words and to focus on the task at hand.
After a 10-minute interval, participants were shown another series of pictures with words overtop. A fraction of these word-pictures were the same as in the first task (“preserved pairs”), while an equal fraction contained the same pictures and words, but in a new combination (“disrupted pairs”). According to the paper, “no connection to the prior task was mentioned.” Immediately afterward, participants were shown the pictures again in a random order and were asked to recall each picture’s previously superimposed word.
The Results
In both experiments, young adults remembered both the preserved pairs and the disrupted pairs equally. They had completely ignored the superimposed words in the first task, so their brains were unaffected by irrelevant information. In contrast, older adults performed much better for the previously seen word-pictures, and much worse for the new combinations. Oddly, participants reported being unaware of a connection between the two tasks. This implies that the older adults didn’t have a conscious memory of the distracting words—only an implicit memory. A follow-up study confirmed that neither young nor older adults had any explicit memories of the pairs in the first task.
The Implications
Contemporary psychologists concede that everyday reasoning and problem solving relies on implicit knowledge and intuition. While older adults are not explicitly aware of the distracting details they wire into their memory, these details still help them intuitively. Their brains’ tendency to “hyper-bind” might make them more implicitly aware of a bigger, more holistic picture than younger adults.
Unfortunately, the older adults often failed to remember the new, “disrupted” word-pairs. The old associations they had wired into their brains made it harder for them to learn new associations.
The Bottom Line: “Life Lessons”
First, try to find a middle ground between focusing your attention and noticing the little details that can help you make more informed decisions. Younger brains may not memorize distractions implicitly, but they can still choose to notice and remember more things explicitly. Second, don’t stay satisfied with the same old rigid associations you have wired in your mind. Try to keep yourself open to perceiving new data that will create new connections. This will make you more informed, and hopefully more rational in your behaviour. In the words of maverick psychiatrist R. D. Laing: “The range of what we think and do is limited by what we fail to notice.”
