Key concepts

What did you have for breakfast last Monday? What color is the floor in your favorite classroom? If you don’t remember the answer to these questions, that’s okay! Your brain is doing exactly what it is supposed to do.

Our brains are nearly perfect storage devices, and part of their perfection is that they know what information to store and what to throw away. Imagine your house if you never tossed anything out—how quickly would it become full of garbage and waste? Your brain is the same way; it stores the information that is useful and important to you and discards the rest. Sometimes your brain remembers things without you consciously telling it to. (You remember the way to your bedroom without ever having had to tell your brain to memorize this information.) Other times we have to tell our brains that information is important. We can do this by paying close attention—and employing a few memory tricks!

Learning and memory are the subjects of a tremendous amount of research and study. Although there is a still a great deal to learn about these brain processes, we do know two of the most important factors for how well we remember something include how closely we are paying attention and whether the memory relates to something we already know. If you aren't paying attention when someone tells you something, there’s a good chance you aren’t going to remember what that person said. (This is why your teachers are always telling you to “pay attention!”. We also tend to form strong memories in novel (new) situations. For example, you can probably recall the first day of the school year much more clearly than the fourth or fifth. Once we get used to a new situation our memories tend be fewer and less specific. Many memory tricks, by contrast, involve taking new information and associating it with something you already know. For instance, if you want to remember that the capital of Mississippi is Jackson, you might imagine your friend Jack swimming in the Mississippi River. Our minds love recognizing patterns and relationships between new and old information. If you can find ways to help your mind do that, you can improve your ability to store and recall information.

In this activity you’ll be exploring the memory capacity of a couple volunteers—and trying out one technique for improving memory known as chaining.


  • Baking tray
  • 24 small household objects (suggestions include: battery, paper clip, rubber band, coin, key, clothespin, key ring, glue stick, toothpick, safety pin, magnet, lip balm, bottle cap, thumbtack, rubber eraser, crayon, pen cap, dental floss, piece of gum or candy, sticker, pebble, small toy, sticky note, tea bag)
  • Wax or parchment paper (enough to cover the baking tray several times)
  • Black marker
  • Several pieces of note paper
  • Pen or pencil
  • At least two volunteer subjects
  • Roll of paper towels
  • Stopwatch or timer


  • Do all of your preparation somewhere private, so your volunteers can’t see your tray before you start the activity!
  • Have volunteers be present separately so the second volunteer does not see the activity while the first volunteer is participating.
  • Spread the parchment paper over your baking tray.
  • Use your black marker to draw a grid on the parchment paper that is four columns across and three rows down. Use all of the space provided by the paper. Number each cell of your grid 1 through 12 starting with 1 at the upper-left corner, filling the first row left to right before starting the second row with five on the left side (12 will be in the bottom-right corner). Make the numbers small and inconspicuous.
  • Arrange your household objects so there is one object in each grid cell.
  • Carefully cover the tray with a paper towel so your volunteers can’t see the objects.


  • Have your first volunteer sit across from you at a table. (Make sure the second one isn’t present for this part of the activity.) Place the covered tray between your volunteer and you.
  • Tell the participating volunteer you’re going to allow 45 seconds to look at the tray. During that time they should try to memorize as many of the objects on the tray as possible. When the time is up, you will cover the tray again and ask them to write a list of all the objects they remember. Do you think it will be easy for them to remember most of the items they see?
  • When your volunteer is ready uncover the tray and immediately start the timer.
  • Remain quiet during the 45 seconds your volunteer is looking at the tray. (Don’t allow your volunteer to write anything down during this time.)
  • When the 45 seconds is up cover the tray and place it under the table so your volunteer can no longer see it.
  • Give your volunteer a piece of paper and a pen, and ask them to get ready to list all of the objects they remember.
  • Start your timer again, and allow your volunteer to spend one minute and 30 seconds listing the objects they remember. When the time is up take the list from your volunteer.
  • Uncover the tray and compare your volunteer's list to the objects on the tray. Next to each object on their list, write the number of the grid cell that object occupied. For example, if there was a rubber band in cell 3, write “3” next to “rubber band” on your volunteer's list.
  • Underneath your volunteer’s list, write down each object they forgot and the corresponding grid cell number. For example, if there was a pebble in cell 8, and your volunteer didn’t write pebble on their list, write “pebble, 8.”
  • Ask your volunteer to turn and face away from you. Remove all of the objects from the tray, and replace them with the 12 objects you didn’t use the first time. Cover the tray again.
  • Before your volunteer turns around, read this paragraph out loud: “Chaining is a technique that can help improve your ability to remember and recall information. It is a form of visualization that involves picturing the object you’re trying to remember. Chaining is especially useful when you have several items you want to remember. To remember the objects, link them together by thinking of images or situations that connect them. For example, if you're trying to remember a grocery list that includes apples, milk, eggs and bread, try chaining these items together in your mind by imagining apples floating in milk. Then imagine eggshells filled with milk. Finally picture an egg sandwich with lots of bread. This technique can help you remember by creating associations between the objects you want to memorize. Now you can try it with this activity!” Do you think your volunteer will remember more objects with this method?
  • Explain that you’re going to repeat the activity, allowing them 45 seconds to remember as many objects as possible, and this time they should try this technique when they’re memorizing the objects.
  • When your volunteer is ready, uncover the tray and immediately start your timer.
  • When the 45 seconds is over, cover the tray and place it under the table so your volunteer can no longer see it.
  • Give your volunteer a piece of paper and a pen, and ask them to list all of the objects they remember.
  • Start your timer again, and allow your volunteer to spend one minute and 30 seconds listing their recalled objects. When the time is up, take the list from your volunteer.
  • Uncover the tray and compare your volunteer’s list with the objects on the tray. Next to each object on their list, write the cell number that object occupied.
  • Underneath your volunteer's list, write down each object they forgot, and the corresponding grid cell.
  • Compare your volunteer’s first list and second list. Which time did your volunteer remember more items? Notice which cell numbers you listed next to the items they forgot. Did they always forget the object in a certain cell? Did they always remember the objects in a certain cell?
  • Ask your volunteer if they used the chaining memory technique. And if so, did it help them memorize the objects? Did they remember more objects during the second time?
  • Repeat the whole activity with your second volunteer. Compare their performance with that of your first. Did either of your volunteers improve on their second try? Did you notice any patterns related to which objects they remembered or forgot? What about which cells they remembered or forgot
  • Extra: Try repeating this activity, but test increasing or decreasing the time allowed for volunteers to memorize the tray. Does the time make a difference? If so, at what point does it make less of a difference?

Observations and results
In this activity you tested your volunteer's short-term memory capacity and then tested the effect of chaining, which is one of the many techniques that can help improve someone's memory and recall.

Results for this activity will vary slightly across different people—every mind is different! You might, however, have noticed some consistent patterns. For example, you may have found both of your volunteers remembered the first or last objects (the ones in squares 1 and/or 12) more clearly than the objects in the middle of the tray (for example, in squares 6 and 7). If this is the case, this could have to do with two memory characteristics known as recency and novelty.

In the case of recency we tend to remember things more clearly when they just happened. If someone tells you a number and asks you to repeat it back to them, it’s much easier to repeat it right after they tell you compared with repeating it the next day. In this case your volunteer might have viewed the last objects on the tray (the ones in squares 11 and 12) right before the time ran out. These objects might, therefore, be easier to recall.

The earliest objects (in squares 1 and 2), by contrast, might have been the first ones your volunteer noticed. In this case the activity was still new and novel to your volunteer. Our brains love novelty—you’ll notice that in their day-to-day lives most people don’t sit and stare straight ahead; their eyes are continuously moving around, taking in new information. Our minds are often sharpened by new situations, and in those cases we tend to have clearer memories of the things we noticed first. If your volunteers remembered the early objects (in squares 1 and 2) the best, it might be because they were especially interested in the task when they first saw those squares!

In the second part of this task you explored whether the memory technique known as chaining had any effect on your volunteers’ ability to recall the objects. This technique is very effective for some people, in part because our brains are good at making associative memories. We often (unconsciously) look for patterns or relationships to help us remember things. For example, when you meet someone named Tom you might immediately think of someone you already know with the same name. This helps you remember the new Tom’s name. In the case of chaining you are creating associations between the objects—even when they don’t exist. If your volunteers found it helpful, suggest to them they should try it in everyday life!

More to explore
Do the Eyes Have It?, from Science Buddies
Study Skills Science: Investigating Memory Mnemonics, from Scientific American
How Many Letters?, from Science Buddies
Sentient Skills Science: What Makes Some Memories So Memorable?, from Scientific American
Science Activities for All Ages!, from Science Buddies

This activity brought to you in partnership with Science Buddies

Science Buddies