Strategy

What is memory?

Simply put, memory is the mental activity of recalling information that you have learned or experienced. That simple definition, though, covers a complex process that involves many different parts of the brain and serves us in disparate ways.

Memory can be short-term or long-term. In short-term memory, your mind stores information for a few seconds or a few minutes: the time it takes you to dial a phone number you just looked up or to compare the prices of several items in a store. Such memory is fragile, and it’s meant to be; your brain would soon read “disk full” if you retained every phone number you called, every dish you ordered in a restaurant, and the subject of every ad you watched on TV. Your brain is also meant to hold an average of seven items, which is why you can usually remember a new phone number for a few minutes but need your credit card in front of you when you’re buying something online.

Long-term memory involves the information you make an effort (conscious or unconscious) to retain, because it’s personally meaningful to you (for example, data about family and friends); you need it (such as job procedures or material you’re studying for a test); or it made an emotional impression (a movie that had you riveted, the first time you ever caught a fish, the day your uncle died). Some information that you store in long-term memory requires a conscious effort to recall: episodic memories, which are personal memories about experiences you’ve had at specific times; and semantic memories (factual data not bound to time or place), which can be everything from the names of the planets to the color of your child’s hair. Another type of long-term memory is procedural memory, which involves skills and routines you perform so often that they don’t require conscious recall.