Source: CLAPPERBOARD: PUBLIC DOMAIN http://commons.wikimedia.org/wiki/File:Clapperboard.jpg
Hello class. So if you remember in the basic process of creating a memory, we have three stages that we go through, that's encoding, storage, and retrieval. OK, so forgetting a memory can result in any kind, or can result from a failure in any one of these processes, in encoding, in storage, or in retrieval. So it's important to differentiate between the terms availability and accessibility of a memory.
So first, let's say if a memory is not available, then there's a problem with either the encoding or the storage of that memory. In other words, you don't have that memory. It's not within your long-term memory. OK, but if a memory is not accessible, then you can still make it available. It can still be inside of your long-term storage, and you can have it, but there's a problem with actually retrieving that information.
OK, so in other words, you can think about a problem with your computer. So if your computer crashes, you might still be able to recover the data. It might not actually be lost on your computer, even though the computer, as a whole, might not necessarily be pulling that information for you. OK, so that information would be available, but not accessible.
So if there's a problem with retrieval, how do you actually recover that data? Well, psychologists have found that certain environmental factors can affect your memory, as well. It's not all necessarily internal in how it works. In fact, external factors can affect the way our memory and retrieval works, as well.
OK, so first, different kind of stimuli around us can influence how memory is actually encoded in our brains. So how we retrieve those memories can also depend on those stimuli, whether they're present or not. This is called a memory cue.
A memory cue is a stimulus that is associated with a memory they can assist in the retrieval of that memory. So for example, if you forgot something you were planning to do in your house when you're walking through it, what you might do is walk back to the room that you actually thought of that thing in the first place, and all of a sudden you suddenly remember what that thing was. That's because the cues around you, the room that you're in, influence how you remember those memories.
So if they're present during the encoding, they can be helpful in the retrieval. This also applies to certain kinds of sensory information especially. So for example, when you're studying, you can associate a specific smell with the things that you're trying to remember, and that can actually help you to recall that information later.
For example, I had a roommate who would study, and he would use the smell of peppermint when he was studying as a bit of a cue. And then when he went into the test, he would actually bring that peppermint with him, and that would help him to, all of a sudden, jog his memory, and to recall all those facts he did while he was studying. It's a little strange, but it actually is effective.
Now a person's own in personal environment can also affect their ability to recall those kinds of memories. State-dependent learning means that memory retrieval can be affected by a person's bodily state at the time of their learning that kinds of information. Or in other words, the factors available in the person's body can affect the encoding, and then they can also affect the retrieval of the information later. For example, if you learned something when you were drinking, and then later you can't quite remember what it was, it'd actually be helpful, and you would be better able to remember that information, if you were to drink something again. So that state of intoxication can help in the retrieval if it was present when you were encoding that information.
This can also apply to states like mood. So for example, when you're sad, you may remember more sad things that you learned when you were previously depressed, which can lead to feelings of more depression and can make you more depressed are more sad after that. So you can see how this can lead to some kinds of psychological issues, as well.