Wednesday, September 15, 2004

How Does Memory Work?

As we start the school year, we are going to learn many new things. We may forget some of that information after a short period of time, but we will remember some of it for years after we learn it. Have you ever wondered why certain memories stay with you for years, while some memories fade away after only a few minutes or hours?

Think of a few events in your life that happened years ago. Your mind probably conjured up something that was relatively significant to you either because it was an important day in your life (like a birthday or holiday), or something to which have an emotional attachment (like a big surprise or an embarrassing moment). You are able to remember these events so long after they occurred because they are stored in your long-term memory.

However, some information is stored only in short-term memory. These are things which we need to know for only a short time after we first learn them. For example, when you look up a new phone number in the telephone book, you can usually remember it long enough to walk over to your phone and dial the number. However, you probably wouldn't remember the number a day later. Saying something over and over in your head, or reading it many times reinforces the items in your short-term memory, and this is how studying for school works.

There is another type of memory called sensory memory, which involves remembering how something looks, sounds, tastes, smells, or feels. This is how most memories start out, but this type of memory can only be stored for less than a second unless it is quickly stored in short-term memory. Sounds and images are transferred most effectively, so if you hear the word "pizza," then the image which comes to mind is much sharper and clearly-defined than the vague (general) memory of how it tastes or smells.

Short and long-term memory involve different processes in the brain, but they are connected and they do interact. For example, the long-term memories that you recalled a moment ago are still fresh in your mind. This is another way of saying that they have temporarily been retrieved to your short-term memory.

Similarly, short-term memories can be stored as long-term memories if they are repeated or rehearsed enough over a long period of time. Taking our phone number example one step further, you know your own telephone number and maybe your best friend's number very well. This is because you have said, written, or dialed them so many times that they were eventually converted into long-term memory.

It is important to note that neither type of memory is perfect. This is why we forget things. In the case of long-term memory, when something is no longer significant, it may begin to fade. So if you move to a different house and get a new phone number, then you might forget your old phone number in a few months since you haven't used it recently. Long-term memory loss can also occur in old age.

Short-term memory loss usually occurs after a piece of information is no longer being reinforced by repetition or use. Also, most people can only store about 7 items at a time in their short-term memory, so "out with the old; in with the new" would be an appropriate way to look at it.

Little Lion Experiment:

Different people learn in different ways. Some are better at recalling images (visual learning), while others are more skilled at remembering sounds (auditory learning). Still others "remember by doing" (haptic learning). Almost everyone uses a combination of the above three methods, but most people lean more heavily towards one of them. To determine which of these memory categories best suits you, go here, scroll down a few paragraphs to the test section, and take the memory test. After you add up the totals for each of the three sections, you can figure out which type of memory you use the most (the higher the number, the more inclined you are to learn in that particular way).