UX DESIGN & COGNITIVE DISTRIBUTION
Herb Simon, a famous Artificial Intelligence and Cognitive Science researcher, wrote “Solving a problem simply means representing it so as to make the solution transparent.” This is true in mathematics as it is with design. While designing human-centered solutions and interfaces, if you follow a certain set of rules, the solution in time becomes evident.
We usually call this a ‘Design Process’ and we can draw guidance from psychology, design principles, heuristics, and even time-management systems.
Cognitive burden refers to the total amount of mental effort being used in the working memory. Cognitive Distribution is a useful concept to have in mind when designing for your users.
“The number of objects an average human can hold in working memory is 7 ± 2. This is referred to as Miller’s Law.”
THE MAGICAL NUMBER SEVEN, PLUS OR MINUS TWO
Human beings have serious limitations with their working memory. This statement is usually based on the psychology paper published by cognitive psychologist George A. Miller: “The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information” often interpreted to argue that the number of objects an average human can hold in working memory is 7 ± 2. This is referred to as Miller’s Law.
In a nutshell, for the sake of offering a mental picture, the experiments resembled something along the lines of the classic 80’s toy game Simon. In this game you must repeat the correct sound and color sequence after the toy played it to you first. In his experiments Miller found that performance is nearly perfect up to five or six different stimuli but declined as the number is increased.
“As we add stimuli to our working short term memory, the memory span — the ability to repeat back immediately after presentation — declines. Our capacity to complete the task is also affected, and the difficulty and time to accomplish it increases.”
RECOGNITION OVER RECALL
As a designer, one thing you can do when creating interfaces is to offload the cognitive burden of the working memory so that the user can have more resources available when interacting with your design.
This idea follows closely to one of Jakob Nielsen’s 10 general principles for interaction design “Recognition over recall” which states: “Minimize the user’s memory load by making objects, actions, and options visible. The user should not have to remember information from one part of the dialogue to another. Instructions for use of the system should be visible or easily retrievable whenever appropriate.”
One interesting system that also uses the same principle of offloading cognitive burden is David Allen’s Getting Things Done Time Management Methodology, which suggests that the first thing that comes to mind that you have to accomplish, you must write it down right away. The idea here is to minimize the amount of working memory cycles spent in remembering such thing by offloading it from your short term memory. In that way you can be more focused and present on other tasks at hand.
This practice is greatly embraced by the League. As soon as we have an important insight, we promptly write it down in a future agenda, a sticky note, or make an action-item in our task management system. As the team’s workload continues to increase, our minds remain sharp and on point by constantly offloading our working memory so we can analyze our research and brainstorm with creativity.
“Mental effort is a finite resource and you should strive to reduce its demands on a user of a design system.”
DESIGN PRINCIPLES FOR REDUCING COGNITIVE LOAD
Another really great resource I came across recently is Jon Yablonski’s 7 Design Principles for Reducing Cognitive Load. In his article he reminds us that mental effort is a finite resource and you should strive to reduce its demands on a user of a design system.
The seven principles are:
1. Avoid unnecessary elements
2. Leverage common design patterns
3. Eliminate unnecessary tasks
4. Minimize choices
5. Display choices as a group
6. Strive for readability
7. Use iconography with caution
Years ago I read that Steve Jobs and Mark Zuckerberg took this principle to an extreme by lowering the amount of trivial decisions they have to choose a day by wearing the same outfit day-in and day-out — You know those black turtlenecks or the gray shirts and jeans they are recognized by — In principle this alleviates their cognitive burden and allowed them to think of world-changing technologies.
CREATING A NATURAL EXPERIENCE
One last thing to help users alleviate their cognitive burden is matching the mental model they have of a system with the new system you are presenting. Whether you do this by basing the system on a pattern your users already perform, or modeling your system on the premise of a known standard. This reflects on your users by creating a ‘natural’ experience they often describe when navigating an interface. Research, usability testing, and iteration are imperative to learn about their models.
In short, make sure to minimize the amount of memory resources necessary to operate your interface, write everything down, and consider wearing the same color shirt for the rest of your life. 🙃
Do you have any other tips? share with us below!
by Dario Fidanza — Project Manager & Product Designer
- Jakob Nielsen’s Heuristics for interaction Design: Recognition Vs. Recall in UX
- George A. Miller’s The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information Link
- 7 Design principles for reducing cognitive load Link
- This blog was inspired by a class on Cognitive Distribution by University of San Diego professor Scott Klemmer