Don’t Forget! Test and Trick Your Short Term Memory!

Introduction

If someone tells you to remember a phone number or address, it can feel like an easy task at first. You repeat the numbers to yourself, either aloud or in your mind. But after just a few seconds, you may find yourself starting to doubt your own memory. Was it 5-7 or 7-5? Our minds are always seeking new and useful information, and as a result, it will try to ‘throw away’ information that seems old or irrelevant, such as a random string of numbers or an address. However, there are ways of helping our minds retain information, and in this activity you will be exploring ways that we lose and keep memories.

Background

Short term or working memory is a way of describing most people’s abilities to store a small amount of information for a brief period of time, in a readily accessible form. Short term memory has a short duration (thought to be on the order of seconds or minutes) but is quickly and easily accessed. People don’t have to stop and think to remember something in short term memory, they can access it quickly and easily. There are many techniques for improving memory retention (capacity to store information over time). Such techniques include visualizing the information in a surprising way, or linking pieces of information together so that one reminds you of the other. In the case of visualizing information, this could be as simple as remembering that you parked your car on the 5^th floor in the D section, by picturing 5 dogs sitting in your car! In addition, linking information could help you remember your grocery list. If you need to purchase cereal, milk, fruit, cheese and eggs, you could imagine the cereal in a bowl, with milk pouring over it and pieces of fruit on the bowl. Then imagine cracking an egg and it’s full of melted cheese! These may seem simple or even silly, but they are time (and scientist) tested methods for improving memory retention. In this activity you’ll test the memory of a few friends and family members, and learn a few tricks for improving memory!

Materials

Observations and Results

You may have noticed that the digits you read for the Single Digit and Double Digit number sequences were the same. However, for the Single Digit sequence you read 10 individual numbers, whereas for the Double Digit number sequence you read 5 double digit numbers. While it’s the same number sequence each time, you may have noticed that your volunteers found it easier to memorize the Double Digit sequence. Your volunteers were able to remember the number “49” as one number, whereas when you said it as “4, 9” they had to remember the numbers 4 and 9 as distinct numbers. To remember information such as number sequences, your brain uses its short term memory storage. Your short term memory has a limited amount of space to store information. As you fill it, there is less room to hold additional information. The number “49” takes up less ‘space’ in your memory than the numbers “4” and “9” do separately. This is a memory technique known as ‘chunking’, and it can help you memorize longer sequences of numbers (and letters!) by chunking them together.

You may have also noticed that more errors were made when the volunteer had to wait longer to repeat the number sequence back to you. Attention and time are extremely important to short term memory function. As more time goes by, it’s more difficult to control our attention. Even when we try to focus on a piece of information, such as a number sequence, retaining that information over longer periods of time becomes more difficult. This is sometimes referred to as the ‘recency effect’, where the more recently something was discussed, the easier it is to remember.

Additional Resources

• Do the Eyes Have It?, from Science Buddies
• The Brain Body Connection: Can Exercise Really Make Our Brains Work Better?, from Science Buddies
• Science Activities for All Ages!, from Science Buddies