Contradictions in Memory
So here’s the conundrum: Why does memory get better when we start adding additional information? That sounds like a contradiction, right? Absolutely! But there’s a good reason why it works, and it has everything to do with the way memory is structured.
Our memory system is a fascinating knot of complementary (and often contradictory!) mechanisms. We need these different systems because our environment is sufficiently complex. We are confronted with many different tasks that include different sources of information. If you have a quick task that will only take a few seconds, then you need a fast memory system that inhales information and spits it out quickly. However, most of the interesting things that we do require us to remember something over a long period of time. You might call that “learning.”
How, then, can we enhance our learning? How can we make sure the information that we see or hear gets cemented in long-term memory? One memory hack is to start adding all sorts of details that will help enhance the memory that you want to form. Here’s an example from my own life.
What's in a name?
A few weeks ago, I met one of my new coworkers. I had no problem remembering her first name, but her last name escaped me. It’s embarrassing when you can’t remember someone’s name, even when you try. I needed help, and here’s what I came up with.
I am a hockey fan, and in college I started following the Detroit Red Wings. They have a history of recruiting promising players from other countries. While these players might not shine during their first year, the Red Wings sign them for extended contracts and commit to developing their talent. A perfect example is when the Red Wings signed Pavel Datsyuk in 2001.
So what does a forward for the Red Wings have to do with remembering my coworker’s name? Well, the first five letters of her last name are “Pavel” (plus some additional letters at the end). In effect, what I did was add a bunch of seemingly irrelevant information to help me remember her last name. I made an effort to embed her name in a larger network of information. Moreover, when I try to recall her name, I have several hooks to get me to the right name. I can think about the field of Cognitive Science, Hockey, or work, and all routes should lead me to the desired destination.
Why does that work? Or said another way, what does the structure of long-term memory look like? I have no idea, mainly because it is so fluid and multi-faceted. However, one way Cognitive Scientists have attempted to visualize the complexity our memory is to use a node-link structure called an Associative Network. A small portion of my network probably looks like this:
Each node is a concept and a link between them is an “association.” In other words, each concept reminds me of the other nodes connected to it. For example, when I think of John, I am reminded of Chas (and vice versa). The degree to which concepts are connected also matters. The distance between Hockey and Cognitive Science is remote. So they shouldn’t remind me of each other.
A STEM Example
This has obvious implications for education. For example, suppose you were teaching a biology class to a group of young children. They know the definition of a “mammal,” and they can give many examples (e.g., cats and dogs) and counter examples (e.g., birds and fish). When they first learned about mammals, they learned that mammals have a couple of defining characteristics: They breath air; they have fur or hair; they have 3 inner-ear bones, they give birth to live offspring; and nurse their young. Most kids at this age, however, incorrectly classify a whale as a type of fish. That means they think whales don’t have hair, don’t give birth to live young (or nurse them for that matter!).
In essence, what you have done as a teacher is completely broken one of the links in their Associative Network and moved it over. Thus, learning might look like this:
==becomes==>
An Associative Network representation helps demonstrate the importance of prior knowledge on learning. It also helps explain other cognitive phenomena like priming, cued recall, and spreading activation (all of which will be the topics of future posts).
Share and Enjoy!
Dr. Bob
For more information
Here is my favorite empirically derived network. It depicts an expert child's representation of her dinosaur knowledge. You can see that some dinosaurs hang together tightly, while others are more remotely associated. Also, the number of links between them also shows the strength of the connection between the two animals.
Used with permission from the author.
