Did you get 3 8 1 4 8 2 5?  Write down your score and compare it to the others! 

What does this mean?

In these experiments, you were asked to remember three lists of seven numbers for the same amount of time. It is probably pretty obvious that time is not the only factor in forgetting. Most likely, you had the least trouble remembering the first number list which was followed by silence. Furthermore, you can probably tell which list of seven numbers is the most frustrating for people to remember, the one with the other numbers after it. Routine speech seems to interfere less with the numbers than other numbers do. Think about how these ideas relate to your own life. You have most likely noticed that cruelest thing someone can do when you are trying to remember a phone number or street address is to shout out other numbers, and the kindest thing someone can do is to simply be quiet.

The name for this problem with hearing more numbers is retroactive interference.  The extra numbers at the end are interfering with your memorization of the first numbers.  There's a good example of this most people are familiar with: oaths or vows.  When the President of the United States takes office, his oath is read to him a few lines at a time, which he repeats.  Imagine if the whole vow were read to him at once and he was then expected to repeat it.  No way!  There are only so many bits of information your short term memory can handle, and when you get too many that are similar, they start interfering with each other.  

While this experiment dealt with retroactive intereference, there is another type of interferece which is exactly the opposite which is proactive interference.  Unlike retroactive interference, proactive interference results from information given prior to that which you attempt to recall. For example, you are less likely to remember the name of someone you meet at a party if you were introduced to dozens of others earlier in the evening. As another example, imagine that you always park in the same spot at work, but today it is taken and you park somewhere else. It would be pretty easy to forget and walk automatically to the usual spot at the end of the day, right? Because of proactive interference, new learning is disrupted by old habits.

So, what can we do to stop earlier information from impairing our recall of following items? Psychologists have found that recall of later items can be improved by making them distinctive from early items. For example, people being fed groups of numbers to remember did much better when they were suddenly fed a group of words instead. This is called release from proactive interference. The more different an item is from those preceding it, the more likely we are to remember it. For example, of four groups that remembered trials of fruit, memory of the fruit decreased with successive trials. However, when the last trial was a vegetable, subject recall improved. Flowers were recalled even better, meats better than flowers, and professions, the category most distinctive from fruit, were most easily recalled.

Just think: if someone said 'chair, lamp, desk, sofa, bed, Saint Patrick's Day,' which would you remember better?
 
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