The Psychologist’s View of UX Design
You may have heard this story about an elephant:
A king brings six men into a dark building. They cannot see anything. The king says to them, "I have bought this animal from the wild lands to the East. It is called an elephant." "What is an elephant?" the men ask. The king says, "Feel the elephant and describe it to me." The man who feels a leg says the elephant is like a pillar, the one who feels the tail says the elephant is like a rope, the one who feels the trunk says the elephant is like a tree branch, the one who feels the ear says the elephant is like a hand fan, the one who feels the belly says the elephant is like a wall, and the one who feels the tusk says the elephant is like a solid pipe. "You are all correct", says the king, "You are each feeling just a part of the elephant."
The story of the elephant reminds me of the different view of design that people of different backgrounds, education, and experience have. A visual designer approaches UX design from one point of view, the interaction designer from another, and the programmer from yet another. It can be helpful to understand and even experience the part of the elephant that others are experiencing.
I'm a psychologist by training and education. So the part of the elephant I experience applies what we know about people and how we apply that to UX design. I take research and knowledge about the brain, the visual system, memory, and motivation and extrapolate UX design principles from that.
This article is a snapshot of the psychologist's view of the elephant.
1. People Don't Want to Work or Think More Than They Have To
- People will do the least amount of work possible to get a task done.
- It is better to show people a little bit of information and let them choose if they want more details. The fancy term for this is progressive disclosure, which I wrote a blog post about recently.
- Instead of just describing things, show people an example.
- Pay attention to the affordance of objects on the screen, page, or device you are designing. If something is clickable make sure it looks like it is clickable.
- Only provide the features that people really need. Don't rely on your opinion of what you think they need; do user research to actually find out. Giving people more than they need just clutters up the experience.
- Provide defaults. Defaults let people do less work to get the job done.
2. People Have Limitations
- People can only look at so much information or read so much text on a screen without losing interest. Only provide the information that's needed at the moment (see progressive disclosure above).
- Make the information easy to scan.
- Use headers and short blocks of info or text.
- People can't multi-task. The research is very clear on this, so don't expect them to.
- People prefer short line lengths, but they read better with longer ones! It's a conundrum, so decide whether preference or performance is more important in your case, but know that people are going to ask for things that actually aren't best for them.
3. People Make Mistakes
- Assume people will make mistakes. Anticipate what they will be and try to prevent them.
- If the results of an error are severe then use a confirmation before acting on the user's action.
- Make it easy to "undo."
- Preventing errors from occurring is always better than helping people correct them once they occur. The best error message is no message at all.
- If a task is error-prone, break it up into smaller chunks.
- If the user makes and error and you can correct it, then do so and show what you did.
- Whoever is designing the UX makes errors too, so make sure that there is time and energy for iteration, user feedback, and testing.
4. Human Memory Is Complicated
- People reconstruct memories, which means they are always changing. You can trust what users say as the truth only a little bit. It is better to observe them in action than to take their word for it.
- Memory is fragile. It degrades quickly and is subject to lots of errors. Don't make people remember things from one task to another or one page to another.
- People can only remember about 3-4 items at a time. The "7 plus or minus 2" rule is an urban legend. Research shows the real number is 3-4.
5. People are Social
- People will always try to use technology to be social. This has been true for thousands of years.
- People look to others for guidance on what they should do, especially if they are uncertain. This is called social validation. This is why, for example, ratings and reviews are so powerful on websites.
- If people do something together at the same time (synchronous behavior) it bonds them together—there are actually chemical reactions in the brain. Laughter also bonds people.
- If you do a favor for me then I will feel indebted to give you a favor back (reciprocity). Research shows that if you want people to fill out a form, give them something they want and then ask for them to fill out the form, not vice versa.
- When you watch someone do something, the same parts in your brain light up as though you were doing it yourself (called mirror neurons). We are programmed with our biology to imitate. If you want people to do something then show someone else doing it.
- You can only have strong ties to 150 people. Strong ties are defined as ties that with people you are in close physical proximity to. But weak ties can be in the thousands and are very influential (à la Facebook).
- I am beginning to think that the whole idea of attention is a key to designing an engaging UI. I'll write more in future articles about that. Grabbing and holding onto attention, and not distracting someone when they are paying attention to something, are key concerns.
- People are programmed to pay attention to anything that is different or novel. If you make something different it will stand out.
- Having said that, people can actually miss changes in their visual field. This is called change blindness. There are some quite humorous videos of people who start talking to someone on the street (who has stopped them and asked for directions) and then don't notice when the person actually changes!
- You can use the senses to grab attention. Bright colors, large fonts, beeps, and tones will capture attention.
- People are easily distracted. If you don't want them to be distracted, don't flash things on the page or start videos playing. If, however, you do want to grab their attention, do those things.
7. People Crave Information
- Dopamine is a chemical that makes people seek… food, sex, information. Learning is dopaminergic—we can't help but want more information.
- People will often want more information than they can actually process. Having more information makes people feel that they have more choices. Having more choices makes people feel in control. Feeling in control makes people feel they will survive better.
- People need feedback. The computer doesn't need to tell the human that it is loading the file. The human needs to know what is going on.
8. Unconscious Processing
- Most mental processing occurs unconsciously.
- If you can get people to commit to a small action (sign up for a free membership), then it is much more likely that they will later commit to a larger action (e.g., upgrade to a premium account).
- The old brain makes or at least has input into most of our decisions. The old brain cares about survival and propagation: food, sex, and danger. That is why these three messages can grab our attention.
- The emotional brain is affected by pictures, especially pictures of people, as well as by stories. The emotional brain has a huge impact on our decisions.
- People's behavior is greatly affected by factors that they aren't even aware of. The words "retired", "Florida," and "tired" can make even young people walk down the hall slower (called framing).
- Both the old brain and the emotional brain act without our conscious knowledge. We will always ascribe a rational, conscious-brain reason to our decision, but it's never the whole reason why we take an action, and often the rational reason isn't even part of the reason.
9. People Create Mental Models
- People always have a mental model in place about a certain object or task (paying my bills, reading a book, using a remote control).
- The mental model that people have about a particular task may make it easy or hard to use an interface that you have designed.
- In order to create a positive UX, you can either match the conceptual model of your product or website to the users' mental model, or you can figure out how to "teach" the users to have a different mental model.
- Metaphors help users "get" a conceptual model. For example, "This is just like reading a book."
- The most important reason to do user research is to get information about users' mental models.
10. Visual System
- If pages are cluttered people can't find information. Use grouping to help focus where the eye should look.
- Things that are close together are believed to "go" together.
- Make fonts large enough. Use fonts that are not too decorative so they are easy to read.
- Research shows that people use peripheral vision to get the "gist" of what they are looking at. Eye tracking studies are interesting, but just because someone is looking at something straight on doesn't mean they are paying attention to it.
- The hardest colors to look at together are red and blue. Try to avoid red text on a blue background or vice versa.
- People can recognize objects on a screen best when they are slightly angled and have the perspective of being slightly above (canonical perspective).
- Color can be used to show whether things go together. Be sure to use another way to show the same info since some people are colorblind.
So, what's your description of the elephant?