Part one dealt with how the brain’s primary and secondary visual cortices organize information that is coming from the eyes. What if you have to do something, like finding two books on different shelves after you set them aside? How do the eyes and brain work together in a situation like the one just described?
Getting back to the example of two books on different shelves, remembering where those two books were located involves working memory. Working memory temporarily stores information in the brain for a short time, while you process and decide what to do with it. Work done at Ohio State University examined how working memory assigns resources.
The study involved people remembering spatial locations, such as two books on different shelves. Participants were shown two dots on a computer screen while their brains were scanned in a functional magnetic resonance imaging (fMRI) machine. The goal was to memorize the location of the dots on the screen. Participants were told that it was more important to remember the location of the dot that appeared in one part of the screen, designating it as a high-priority item.
The two dots appeared on the screen at the same time for a half-second. Twelve seconds later, participants were asked where one of the dots appeared. Most of the time, the participants were asked where the high-priority dot had appeared. Approximately 30 percent of the time, they were asked where the low-priority dot had appeared.
Scientists found that they could see the activity in the visual cortex of the brain, as the participants tried to memorize the location of the dots. The high-priority dot was represented more precisely, while the low-priority dot was represented with less resolution. When the participants indicated where they had seen the dot, they placed the high-priority dot closer to its actual location than they did with the low-priority dot.
That’s not all the scientists learned. When they analyzed the fMRI scans, they found out that the frontal cortex of the brain was communicating with the visual cortex, and frontal cortex was instructing the visual cortex on what level of resources to allocate in order to remember the location of each dot. This finding is significant since neuroscientists have long wondered which part of the brain is responsible for working memory involving visual objects.
This study showed that both the visual cortex and frontal cortex play roles in working memory. The visual cortex creates the visual representation of the two dots, while the frontal cortex decides which dot receives more working memory resources and which one receives less.
Both studies demonstrate how the eyes and brains work together to help us get things done. Whether it is seeing carrots at the supermarket and remembering to include them in our Super Bowl party snack tray or seeing books on a shelf and recalling that one belongs on the top shelf and another in a different room, the eye and brain are working together to categorize and remember the right things.
Of course, when you get the carrots for the snack tray, don’t forget the ranch dressing.
Source:
https://news.osu.edu/watching-our-brains-remember-multiple-things-at-once/