New research shows that people may have to “turn on” or prompt their memories to help them remember even the simplest details.
Findings from the Pennsylvania State study indicate that memory is far more selective than previously thought, according to researchers.
“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,” said Dr. Brad Wyble, an assistant professor of psychology.
“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.”
For their study, Wyble and Hui Chen, Ph.D., a postdoctoral fellow in psychology, tested the memories of 100 undergraduate students. The students were divided into several groups. Each group performed a variation of the experiment in order to replicate the results for different kinds of information, such as numbers, letters, or colors.
In each trial the students were shown four characters on a screen arranged in a square — for example three numbers and one letter — and were told that they would need to report which corner the letter was in.
After a set amount of time, the characters disappeared from the screen and the students reported where they remembered the letter had been. This part of the task was expected to be easy and errors were rarely made, according to the researchers.
After repeating this simple task several times, the student was asked an unexpected question to probe the memory for the very information used to find the letter’s location.
Four letters appeared on the screen and the student was asked to identify which one had appeared on the previous screen. Only 25 percent of the students identified the correct letter — the same percentage as would be expected to randomly guess it, the researchers noted.
Similar results were obtained when the students were asked to locate odd numbers, even numbers and colors.
“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,” said Wyble.
Chen and Wyble call the phenomenon they observed attribute amnesia. Attribute amnesia occurs when a person uses a piece of information to perform a task, but is then unable to report specifically what that information was as little as one second later.
“The information we asked them about in the surprise question was important, because we had just asked them to use it,” said Chen. “It was not irrelevant to the task they were given.”
After the surprise trial, the same question was repeated on the next trial, however it was no longer a surprise. Participants did dramatically better, with the average of correct answers between 65 and 95 percent across the different experiments, the researchers reported.
The study’s findings suggests that people’s expectations play an important role in determining what they remember, even for information they are specifically using, according to the researchers.
“It seems like memory is sort of like a camcorder,” said Wyble. “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.”
Wyble and Chen argue this selective memory storage might be a useful adaptation because it prevents the brain from remembering information that is probably not important. The researchers plan to continue this line of research as they study whether people are aware of their own lack of memory.
The study, supported by the National Science Foundation, was published in the journal Psychological Science.
Source: Penn State