How does psychology define memory? Think of memory as a bank. Think about your checking account and your savings account. Each of these accounts does something a little different with your money because they have different purposes. Checking accounts typically function for everyday and short-term use. Savings are intended to be for longer-term storage. Your memories store information in different ways as well.
Three separate storage systems are involved with memory: sensory memory, short-term memory, and long-term memory.
Sensory storage
Sensory memory is a split-second memory system that stores information coming in through your senses. Have you ever looked at the sun and then closed your eyes and looked away? What happens? You can still see a type of sun in your mind. This afterimage is a visual sensory memory known as an iconic memory.
For auditory stimuli, it is called echoic memory. This process happens so fast that it is sometimes considered a part of the perceptual process, but is, in fact, part of the overall memory system.
Short-term memory
Short-term memory (STM), also known as working memory, consists of the information that is active in your consciousness right now, the things you’re aware of. The light on the screen, these words being read, and the sound of traffic outside your window are all parts of your conscious awareness, and they’re all being stored in your STM. Things you are not aware of can simply be forgotten in many cases.
How much information can your STM store? The general consensus is that it can store seven items of information, plus or minus two items. This is sometimes called the “magical number seven” of STM capacity.
Does that mean that you can only store seven words, seven numbers, or seven other simple items in your STM? No. Thanks to a process called chunking, you can store a lot more information than that. A classic example of chunking is the use of mnemonics, which enables you to take a big chunk of information and break it down into a little phrase, so it’s easier to remember.
Here’s an easy way to form a mnemonic. If you have a list of things you want to memorize, take the first letter of each word on the list and make a catchy phrase out of it.
Here’s an example: “Kings play chess on fine green silk.” Do you know what that stands for? It stands for the way biologists classify different organisms on the earth: Kingdom, Phylum, Class, Order, Family, Genus, and Species.
The duration of memory for the STM system is approximately 18 seconds. You can extend the length of time that you store information in STM only by engaging in something called rehearsal. Rehearsal is the process of actively thinking about something. Rote rehearsal is repeating something over and over again in your mind or out loud so that you don’t forget it.
Long-term memory
If the information in STM is rehearsed long enough, it eventually ends up in your memory’s savings account, the long-term memory (LTM). You basically have two ways to deposit information into your long-term memory bank:
Maintenance rehearsal: You transfer the information from your STM through repetition until it’s committed to long-term storage.
Elaborative rehearsal: Your mind elaborates on the information, integrating it with your existing memories. When information is meaningful and references something that you already know, remembering is easier and forgetting becomes harder.
The more you process the information, linking it to what you already know, the better you will remember it!
You can break down the LTM into three basic divisions:
Episodic memory: Events and situations unique to your experiences (marriages, birthdays, graduations, car accidents, what happened yesterday, and so on)
Semantic memory: Factual information such as important holidays, the name of the first president of the United States, and your Social Security number
Procedural memory: Information on how to do things like riding a bike, solving a math problem, or tying your shoes
Theoretically, the size and time capacity of LTM is infinite because researchers haven’t found a way to test its capacity. It has enough capacity to get the job done. This may sound kind of strange when you consider how much information you seem to forget. If the information is in there somewhere, why do you forget it?
