By Richard Restak, MD, The George Washington University School of Medicine and Health Sciences
Edited by Kate Findley and proofread by Angela Shoemaker, Wondrium Daily
Why do some people (especially children) seem perpetually disorganized, while others have it all together? Dr. Restak demystifies working memory, which is responsible for planning and executive functioning, and its relationship to long-term memory.
The Brain and Working Memory
Working memory is the part of short-term memory responsible for helping you juggle multiple streams of information, such as searching for your keys while getting ready for work. Eventually, some of the information in our working memory will get stored in our long-term memory.
The frontal areas of your brain are responsible for handling working memory. In the 1930s, Carlyle Jacobsen, a physiologist, studied the effects of injuries to the frontal lobes on monkeys.
The injuries were such that if you put food in one of two trays, the monkey would look at it and reach for that food. Later, though, if you put a curtain down for a few seconds and then raised the curtain, the monkey would not remember which tray had the food.
A short delay was creating a failure in remembering where the food was. These were the monkeys with frontal lobe injuries; they couldn’t point to the dish where they had previously seen the food.
Subsequent studies by neuroscientist Joaquin Fuster and others established that parts of the prefrontal cortex, the area of the brain responsible for planning and decision-making, are devoted to retaining information despite delay. The monkey was unable to remember which tray the food was in due to this delay.
Our Brain’s “Scratch Pad”
Classic memory tests are actually working memory tests.
“I sometimes ask people I’m evaluating to remember four items, and then I ask them about them after a four-minute delay,” Dr. Restak said. “I might say something like, ‘apple, Mr. Johnson, charity, and tunnel.’ They will repeat it, and then I’ll ask them about it four minutes later.”
Think of a scratch pad maintained in the frontal lobes that the rest of the brain can then consult and become familiar with over time. The left frontal cortex is important for verbal working memory, as the left hemisphere mediates language. The right frontal cortex is concerned with visual-spatial processing.
Since working memory depends primarily on the prefrontal cortex, it varies with age. Working memory, for example, is very poor in children. As a result, young children have difficulty organizing themselves, keeping their attention focused, and managing more than one or two things at a time.
The dorsolateral prefrontal cortex is especially important. It forms an internal representation or mental snapshot, and it helps you to retain focus such as when you are searching for a missing item.
Working Memory and Long-Term Memory
If working memory is a scratch pad, long-term memory is its filing system. Long-term memory is subconscious.
Consider every item of information you know. You might know a lot of things, but many of these things you know how to do subconsciously, such as brushing your teeth or riding a bike. The information on how to perform these actions is stored in your long-term memory.
Working memory, however, is active thought. Planning your itinerary for your vacation or organizing a birthday party, for example, are actions you perform while concentrating on them.
A transfer occurs from working memory into long-term memory. Long-term memory organizes knowledge into complex concepts or schemas, and it’s aided by working memory.
Our intelligence is related to our ability to transfer information from working memory to long-term memory. Students with low working memory skills are prone to misunderstandings and mistakes in class and on tests.
The greater the working memory, the higher the verbal score on the Scholastic Aptitude Test (SATs) and on IQ tests. These students also do better on standard nonverbal tests, which test students on the ability to analyze visual sequences, relationships, and patterns.
You can take steps to improve your working memory such as engaging in memory games. This will not only help to prevent memory decline that typically accompanies aging, but can also enhance your overall intelligence.