The study offers a picture of how the brain handles a lot of information

A new study offers a picture of what is happening in our minds when our working memory has to use its limited resources to remember many things.

Researchers have found that two parts of the brain work together to ensure that more brain resources are given to remember a priority element when a person weighs more than one elements in memory.

The study included people who remember spatial sites. Imagine seeing two books on different shelves of a full library that had not been settled in any order. How could you remember where it was if you returned a few seconds later?

This is the job of working memory, which temporarily stores information in your brain for a short period of time, while editing and deciding what to do with it, said Hsin-Hung Li, chief author of the study and assistant professor of psychology at the University of Ohio.

In this study, recently published in the magazine Scientific progressLee and his colleagues observed the activity in the brain, while people tried to remember the position of two objects.

Very often when you try to remember many things, one item can be more important than another.

What we have found is that the most important element is represented in the brain more accurately, while the least important element is given much lower resolution. “

Hsin-Hung Li, Head of Study Author and Assistant Professor of Psychology, Ohio State University

In the example of the library, you may remember exactly where on a particular shelf was the most important book. But you may only know that the least vital book was somewhere in the upper left corner of the library.

The study involved participants whose brain was scanned on a FMRI machine while looking at a screen. They showed two dots and their goal was to memorize their positions on the screen. Participants said it was more important to remember the place of the dot that appeared in an area of ​​the screen-this was the high priority element.

The two dots appeared on the screen at the same time for half a second. Twelve seconds later the participants were asked where one of the dots appeared. Usually, they were asked where the high priority dot appeared. But about 30% of the time, they were asked to indicate where the low priority dot had appeared.

The researchers found that they could see activity in the visual cortex of the brain, as participants attempted to memorize the position of the dots, Lee said. The high priority dot was represented more accurately, while the low priority dot was represented more coarsely, with less resolution.

This brain tactic worked. Later, when the participants reported where they had seen the dots on the screen, they put the high priority dot closer to its real position than they did with the low priority dot.

The researchers found something else when they analyzed FMRI scanning – the frontal cortex of the brain communicated with the visual cortex, telling it the level of resources it must allocate to remember the position of each dot.

“With limited memory resources, the frontal bark decides which dot will get more resources, so we will remember more accurately,” Li said.

This finding was important because neuroscientists had discussed which part of the brain – the frontal cortex or visual cortex – is responsible for working memory that includes visual objects, such as dots in this study.

“We found that both had a role. The visual cortex creates the visual representation of the two dots trying to remember people,” he said.

“But the frontal cortex makes this decision to allocate about who to get more work -memory resources and who to get less.”

Another unique part of this study was the fact that the researchers decoded the brain activity of people who consider two different things at the same time for each test, which has rarely been done.

“It’s a very useful technique and I think scientists will use it more in the future. There are so many situations in which people try to keep many thoughts in their minds and it is very useful to be able to decode more than one,” Li said.

This project was supported by the National Institutes of Health, Alfred P. Sloan Research Fellowship, UCSB Academic Senate Grant and Swartz Foundation Postdoctoral Fellowship.

Lee did a research at the University of New York, where he received his doctorate and was a postdoctoral researcher. Other co-authors in the study were Thomas Sprague, a former NYU postdoctoral collaborator now at the University of California, Santa Barara. And Aspen Yoo, Wei Ji Ma and Nyu’s Clayton Curtis.