Covering the Spread: Spreading Activation

"Oh, rats!" —Indiana Jones

Let's play a game. What do the following three things have in common?   

blue       cake       cottage

One is a color, the second is a type of dessert, and the last is a little house in the woods. It doesn't seem like they have much in common. But there is one concept that binds them together. Keep thinking about it. Or don't! Sometimes the best way to see the connection between (seemingly) related things is to leave it alone and let your mind engage in some background processing.

Switching gears a moment...let's talk about what it means to be "reminded" of something. For example, I had lunch with one of my coworkers, and she told me about this man who randomly stopped by her house when she wasn't home, and he left some candy on her front porch. Her story reminded me of a movie that my wife and I recently watched about a guy who wants to be a freelance journalist. So wait a minute...What does a guy leaving candy at my friend's house have to do with a movie about journalism? Well, the movie is entitled Nightcrawler, and the connection I saw was "anti-social behavior" (or maybe even "mental illness!"). This type of thing happens all the time in conversation. Something one person says reminds another person about a completely different topic. How does that happen?

Back to the Network

One potential explanation is to return to an idea that was introduced in a previous post. I made the claim that an Associative Network is a very powerful way to represent someone's knowledge. It is powerful because it can explain other cognitive phenomena, such as "reminding." When we say something "reminds you" of something else, what are we talking about? And how can we use that information to map someone's knowledge?

One of the properties of a network is called the "connection strength" (or proximity) between two concepts (or nodes). For example, apples are strongly associated with bananas because they are both types of fruit. But apples are only very remotely associated with the Kentucky Derby. (It's a long walk, but you can imagine the following chain of associations: Horses eat apples, which give them energy to run, and people like to watch horses race at the Kentucky Derby.) 

That means something can remind us of another thing either by the strength of the connection between them or the number of hops you need to connect any two concepts. Back to the original question: According to this theory, how does "reminding" work? The theory states that each node is connected to one (or many) other nodes. When that node becomes active, due to some stimulus in the environment, activation spreads throughout the network of ideas. Back to our fruit example, if I see an apple, then activation spreads out to other fruit, including bananas, and continues to radiate outward to other concepts. Spreading Activation, then, is the idea that one node becomes active, which activates  another node, which then activates a third node, and so on until the activation dies out.

A STEM Example

I like the idea of an associative network of ideas because, as an educator, you can start to bootstrap your lessons based on what your students already know. A perfect example is Netwon's Law Universal of Gravitation, which is summarized by the following equation:

F represents the force between two objects (e.g., the sun and the Earth), G is a constant, m is the mass of the first and second object, and r is the distance between them. It is extremely helpful to know this particular equation when students later learn Coulomb's law, which describes the force experienced by two charged particles:

Notice anything? There are subtle differences between the two laws, but the overall structure of the equations is remarkably similar. In fact, when teaching Coulomb's law, it is helpful to ask the students if they are reminded of anything from their previous lessons.

Back to the Beginning

I opened this post with a "game." It's origin isn't a game, but a test of creativity called the "Remote Associates Test" (or "R.A.T." for short). The idea is that creative individuals have many connections between nodes and when activation spreads, it hits remote parts of the network. This makes intuitive sense because creative people are most likely to be described as "divergent thinkers." Now we have a way to visualize what divergent means. Maybe we can even train ourselves to be more creative by not stopping at the first thing that you are reminded of. Instead, force yourself to keep activating other parts of your associative network.

Share and Enjoy!

Dr. Bob

For More Information

You can test your creativity by taking the RAT here. Also, remember the overused phrase, "think outside the box"? Ever wonder where that came from? According to internet lore, its origin is found in the "nine dot problem" where you have to connect all of the dots with only 4 lines. Try it!