Memory has to be ‘turned on’ in order to remember even the simplest details, a new study finds.
When not expecting to be tested, people can forget information just one second after paying attention to it.
But, when they expect to be tested, people’s recall is doubled or even tripled.
Dr Brad Wyble, one of the study’s authors, said:
“It is commonly believed that you will remember specific details about the things you’re attending to, but our experiments show that this is not necessarily true.
We found that in some cases, people have trouble remembering even very simple pieces of information when they do not expect to have to remember them.”
In the research, published in Psychological Science, one hundred people were shown sequences of numbers and letters and told they would be tested on the position of the letters (Chen & Wyble, 2015).
People performed very well on this task, rarely making a mistake.
But, then the task was tweaked slightly: unexpectedly they were asked about whether they had seen previous letters before, rather than just being asked about the position of the letters.
Suddenly people performed poorly on this test, which is surprising because they had remembered the position of the letter, but apparently not what the letter was!
From almost perfect recall for the letter’s position, which they were expecting to have to recall, people performed no better than chance in recalling the letter itself.
Dr Wyble said:
“This result is surprising because traditional theories of attention assume that when a specific piece of information is attended, that information is also stored in memory and therefore participants should have done better on the surprise memory test.”
Once people knew they were going to be tested on the letters themselves, though, their performance improved dramatically.
Instead of getting around 25% correct (which was chance in this experiment), their success rate shot up to between 65 to 95%.
It may be that this represents a useful adaptation: so that important memories — ones which we are more likely to need and use — are more strongly encoded in memory.
Dr Wyble said:
“It seems like memory is sort of like a camcorder.
If you don’t hit the ‘record’ button on the camcorder, it’s not going to ‘remember’ what the lens is pointed at.
But if you do hit the ‘record’ button — in this case, you know what you’re going to be asked to remember — then the information is stored.”
Image credit: Flood G.