Designing for the User's Two Minds

The human mind functions on two levels: the conscious and the unconscious. Most designers think only about the conscious mind when they design. We need to address both the conscious and the unconscious mind. But first we need to better understand the conscious mind.

We often think of the unconscious like a car that is always running, and of the conscious part of our mind like the driver of the car. In fact, consciousness is more like being the rider on the back of an elephant. We know consciously what we want to do, and we encourage the elephant to do what we want, but the execution of tasks is handled by the unconscious. Our conscious mind can only monitor the execution of the task.

The human brain continuously runs hundreds, thousands, or possibly even hundreds of thousands of parallel processes all the time. However, it's not running hundreds or even several conscious processes. The conscious mind is a single process of the brain. We move processes from a conscious level to an unconscious level to try to keep our conscious mind free.

Since we have only one process for consciousness, our conscious mind cannot attend to more than one task at a time unless we switch between them (at the risk of not keeping up with some of them, or not doing any of them well). The more we have to focus on a task, the less we are able to do anything else. We actively stop attending to things around us and discard things that are not part of the task we are trying to accomplish.

Consider the following video. (Go ahead take a look at it. I promise I'll wait.)

If you were able to correctly count the number of passes that the team in white made, it's likely that you missed what else was in the video. Conversely, if you saw the thing in the video, you probably did not get the number of passes correct.

When our conscious mind is focused on a task, our unconscious mind works without a monitor.

Have you ever been taking a shower, got thinking about something, and then couldn't remember if you washed your hair, even though you did? Your unconscious mind always washes your hair, and your conscious mind is usually aware of it happening (unless, of course, you've discovered something more interesting to think about).

Have you ever been engaged in conversation on your phone in the car (something you should not ever do for so many reasons that I won't go into right now) and found yourself missing a turn, taking a wrong turn, or even driving someplace that you didn't intend to go? Your unconscious mind is always driving the car; left to its own devices, it will follow previously learned directions.

The unconscious mind expects things to be routine. It doesn't work well with exceptions. Have you ever found yourself hitting the OK button instead of a Cancel button because they were reversed left and right from where you expected them to be (sometimes even while watching yourself do it but unable to stop yourself in time)? That's your unconscious mind trying to follow what it assumed to be the standard, learned, or intuitive design rule-it just missed the exception in this case.

What we display on the output screen has to be designed for our user's conscious mind. How the user gets to that screen, or how to change things on that screen, needs to be designed for the unconscious mind to allow the conscious mind to remain focused on the goal. When a design requires the user to stop paying attention to the goal to think about how to use the interface, the user'sattention is split and they have to work that much harder to do both tasks. This is when mistakes happen. This is why users get frustrated. This is why users decide they aren't very happy with what we've designed, even though the product can do what they want.

As designers, we need to design for the user's two minds.