Getting Out of Your Head: External Cognition

Here's a fun little game. Enter a number, any number, in the left text box marked "Input." Then look at the right side of the box. What's going on inside the box [1]? 

InputOutput

One of the fundamental concepts in computer science is the distinction between input and output. Input is the information that gets used by a program, and output is the result of any sort of manipulation that happens to that input. At the highest level of description, every computer program can be described as: input => processing => output. The power of a program comes from the ability to link together smaller sub-processes so that the output of one process can become the input for another process [2].

For the past forty years, Cognitive Science has benefited from thinking about human cognition in these terms. In other words, many scientists think about the mind like a computer that can be broken down into components that are responsible for processing certain types of information. It's useful to track the information that is used as input (e.g., stimuli) and what gets generated as output (e.g., behavior).

However, within Cognitive Science, there is a group of people who don't necessarily believe that all cognition needs to take place strictly in the mind. Instead, some of our cognition (i.e., the processing phase) can be offloaded to the outside world. Does this really happen? If so, how can we use this to our advantage?

"Luke, Use the Force(ing Function)" --Ben Kenobi

Probably the most basic and simplistic example of external cognition is writing something down. We take notes for a variety of reasons. First, most of us have an accurate mental model of our memory and realize that it is fallible. Through experience, we realize that we will not remember all of the details of everything that we see or hear. Second, there's evidence that merely taking notes helps us better encode the information; therefore, we externalize our memory in hopes of improving both encoding and storage.

In a previous post, I made the claim that cued recall is almost always easier than free recall. Because of that fact, we can use it to our advantage. One way to exploit cued recall in everyday life is to systematically embed clues in our environment to help us remember easily forgotten tasks. One of my favorite memory tricks is called a forcing function. For example, to start your car, you need your car keys. In other words, you are forced to grab your keys to drive your car. Now suppose you have a letter that you need to mail tomorrow; unfortunately, it's likely that you will forget because mailing a letter isn't part of your normal morning routine. So what should you do with it? Based on the lovely feature of cued recall, I am going to put the letter under my car keys so I am forced to remember it. I could tie a string around my finger (like they did in the old days), but that's not a really great cue because the association between letters and strings is completely artificial. A forcing function is a great way to help you remember. The external environment is now tasked with "remembering" something for you.

Engineers who understand the limitations of memory and attention use forcing functions in their designs. My favorite example of a forcing function was the way I locked my Volvo 240 station wagon. I had to insert my key into the outside lock and twist it to engage the power locks. In other words, I had to stand on the outside of my car, with my keys in my hand, to lock my car. There was no way to lock myself out [3].

"Roger, Roger. What's our vector, Victor?" --Captain Oveur

External cognition can be much more than a memory aid. It can also assist in the actual process of thinking and reasoning. One of the oldest tools for externalizing cognition is the abacus. Humans are perfectly able to carry out mental computations; however, working memory tends to fill up quickly as we chain together calculations. Thus, an abacus can help increase the speed and accuracy of our mental calculations by externalizing the interim numbers.

Here is another, far more complex, example of external cognition: landing an airplane [4]. When a plane is about 30 minutes away from the airport, the pilot and co-pilot begin calculating the speed at which they will eventually land their plane. While this might sound simple, it is far from it. Why? Because the landing speed is largely a function of the airplane's weight. The weight of the plane is influenced by the amount of fuel onboard. As the plane flies and burns fuel, it becomes lighter. Given the association between speed and weight, the pilots need to project the weight and speed of the plane at the time of landing. 

In addition to adjusting the speed, pilots can also reconfigure the shape of the wing by changing the angle of the leading edge, extending the overall length of the wing, and setting the angle of the trailing edge (i.e., the "flaps"). The goal of reconfiguring the wing is to maximize lift while minimizing the plane's speed when landing. 

To configure the optimal settings of the shape of the wing and the plane's speed, the pilot has several artifacts at her disposal. First, there is the instrumentation of the cockpit. Various gauges and meters help pilots understand their current altitude, speed, and bearing. Second, they also have a card that they carry where they can look up the minimum speed for different increments of weight crossed with the flap configuration of the wing. This is a simple representation for humans to use because we are better at visually scanning rows and columns of numerical data than we are at computing the value of a complex, multi-factor function. Finally, they have each other. The pilot and co-pilot work together to make sure they do not skip any steps while making this calculation.

The STEM Connection

How can we use the ideas from external cognition and forcing functions in the classroom? Obviously students would like to externalize their memory by taking notes. Some students take copious amounts of notes. This might help some, but hurt others. The reason why it might hurt others is because we are serial processors, and we can only process one stream of information at a time. For these students, maybe it would be best if the teacher supplied the notes. Alternatively, the student can listen to the lesson and take notes from the textbook outside of class. 

Another application might be to make "external cognition" into an assignment. Some (probably most) students benefit from making the lesson concrete. One way to make something concrete is to create an actual artifact that can be used. Going back to the pilot example, they created a table so that they can look up the speed given the aircraft's weight and wing configuration. Students could construct an analogous representation for complex relationships. For example, in statistics, we had tables that we used to look up the critical value for a t-test given the degrees of freedom and the significance level.

Finally, and this is kind of a stretch, but you can teach your kids about forcing functions, especially if they are particularly prone to forgetting (e.g., remembering to take home their textbook or to return a permission slip).

Humans are extremely smart. One of the reasons why we are smart is because we are able to recognize our limitations and structure the external environment to help us overcome our shortcomings. Knowing about external cognition can help us become even more intelligent! 


Share and Enjoy! 

Dr. Bob

For More Information

[1] Special thanks to Josh Fisher for creating The Blackbox Game. Check out his google+ page for more fun and creative widgets that he has assembled!

[2] One of the strengths of our species is that we don't have to solve the same problems that others have solved in the past. In other words, I don't need to rediscover algebra from scratch to use it to solve problems. Instead, I can rely on the hard work from the people who have come before me. This is very much true in computer science where individuals will solve a particularly difficult problem for the rest of the community and then post their solution in a library for a particular programming language. For example, if you have neither the time nor expertise to write a parser that will pull apart time and dates in Python, that's already been done for you. A similar arrangement could also be done in the classroom. 

[3] Actually, that's not entirely true. If you open the passenger door, walk around to the driver's door, lock all of the doors from the outside, walk back around to the passenger side, throw the keys in, and close the door, I would be locked out. Thankfully, I was never that stupid.

[4] Hutchins, E., (1995) How a cockpit remembers its speed. Cognitive Science, 19, 265-288.