Thanks to Bestica’s generosity, I was able to attend the CHI2012 conference in Austin, TX in May. There were a number of great workshops and sessions that took place, but in order to do a deep dive, I have decided to focus on one particular workshop.
During CHI2012, I was fortunate enough to attend the Designing With the Mind in Mind workshop with Jeff Johnson of UI Wizards in San Francisco. Johnson discussed in detail the psychological basis behind many well-known UI design principles, guidelines and heuristics; particularly in how they relate to perception and cognition.
He opened by saying that design rules are not just simple recipes. A designer must understand the underlying psychology behind the rules before he or she can apply them effectively. Gaining a deeper understanding of the psychological basis for these design rules allows us to apply them judiciously, and is especially useful when the rules appear to contradict each other. Arming ourselves with knowledge about human perception, learning, memory and problem solving is the key to understanding design rules.
First, web designers need to understand the scientific underpinnings that led theorists like Schneiderman, Nielsen, Molich, Stone, and others to draw up the UI Design Guidelines, which were developed according to how people perceive, think, learn and act. We need to determine how each rule could be applied and the different ways it has been used when balancing trade-offs between competing rules. Johnson went over several UI guidelines during his talk:
1. People perceive what is expected:
How we perceive is biased by our past, our present and future goals, our past experiences and context.
2. People’s vision seeks structure:
Our vision is optimized to see structure. Proximity, which is one of the gestalt principles of visual perception, impacts how we see structure. Items very close together are seen as grouped together (note the pe....
Another gestalt principle, closure, is responsible for our tendency to see whole, closed objects and not collections of fragments.
Symmetry influences our tendency to see simple figures rather than complex ones.
Common fate describes our inclination to view items that move together as grouped objects.
There are additional gestalt principles but these were the main ones we reviewed in the workshop.
3. Reading is unnatural:
Tailoring UI solutions to our natural strengths is the goal. So, knowing that reading is unnatural and it’s a skill that takes years to learn, is essential. People are hard-wired for language but not for reading. Factors that impact how easy it is to read text include the backgrounds behind text and low contrast between the type and the b....
4. Color vision is limited:
Our color vision is limited, as shown by this example from Edward H. Adelson. We see contrast found on the edges of an object and not absolute color levels. People also have trouble discriminating between pale colors, smaller color patches and separated patches. Because of this, it’s best not to design something that solely requires color to distinguish it from other items. Use an additional design cues and make sure colors differ in saturation as well as hue. Test your design work by viewing it in grayscale.
5. Peripheral vision is poor:
Because our peripheral vision is poor, it’s best to place things like error messages and their icons where the users are looking.
6. Attention is limited, and memory is imperfect:
Attention is a form of short-term memory and it focuses on what is happening right now. It was once thought that short-term memory could hold 5 to 9 items with 7 being the mean. Now the latest research suggests 5 to 9 numbers of items was too high. The revised range for short-term memory is 3 to 5 items with 4 being the mean. When new items are introduced they grab our attention away from the older items in short-term memory. Because of the limits of short-term memory, people forget goals and information quickly. Here is an example of an error message that has too much information for short-term memory. Note that the needed instructions to fix the problem disappear when you click “OK”. To avoid forgetting, it’s likely that a person would write down the error message or try to take a screenshot of it. Keeping track of things in short-term memory is actually hard work.
7. Cognition is easy:
As a species, we evolved to recognize objects quickly. This skill was necessary for our survival. We have the ability to assess situations and identify faces very quickly. We can also recognize complex patterns, like the ones found on a jaguar or leopard.
8. Recall is hard:
On the other hand, we did not evolve to recall arbitrary facts. To compensate, we use tricks like songs to help us remember the alphabet or spell the word “Mississippi.” We actually developed writing to avoid memorizing and we often make cheat sheets or take notes to help us remember. Software programs that help store passwords and calendars compensate for the limits of our memory. Many people don’t learn all the shortcut keys inside a software program. Although it’s slower, it’s easier to browse and select than to memorize shortcut keys.
Generalized learning is easy for us. We can remember such things as stay away from leopards, don’t eat bad-smelling foods and don’t open attachments from unknown senders. The down side to generalizing is that we have a tendency to overgeneralize.
On the other hand, it’s very hard to learn new things. For example, to use new cooking recipes, we often rely upon aids such as cookbooks. Learning new actions also is difficult. It’s easy to recite the alphabet starting with “A”, but hard to do it backwards starting with the letter “Z”. Also, doing calculations is difficult and we often rely upon spreadsheets and calculators to help us with these tasks.
So, there you have it. These were most of the topics that Jeff Johnson shared during his workshop. I highly recommend attending his workshop Designing with the Mind in Mind, should you have the chance.