Design for Cognition
Let’s chat about Cognitive Load Theory** and how we can use it to design experiences, interactions, and communications better in tune with how our brains work.
A person’s cognitive load is the total mental effort to process information. Everything comes into our working memory, and only some things pass on into our mid- or long-term memory. If we overwhelm someone’s cognitive load, we get in the way of their brain’s ability to process or use the new information-changing behavior, make decisions, teach it to someone else, and take action.
There are three types of stimulus that make up our cognitive load:
Intrinsic load is the effort to move new information from working memory into mid- or long-term memory.
Germane load comes from the activities, materials, and work (deep processing) of new information during the act of learning (connecting new knowledge to existing knowledge).
Extraneous load is input that disrupts, distracts, and takes up working memory but is not intrinsic (the information itself) or germane (supportive of learning).
The Bad News
- As soon as the sum of intrinsic, germane, and extraneous stimulus exceeds our working memory and overwhelms our attention, all bets are off for learning or the use of information.
- It is surprisingly easy to overwhelm someone’s cognitive load-working memory, which only has room for 5–9 items, and only 2–4 of them can be processed simultaneously.
- Our attention is what filters input selecting what will receive further processing. If the input is not noticed and pulled into working memory within 15 seconds, it is discarded.
- Lastly, it isn’t until our 3rd review of new information that we are likely to retain it on a long-term basis.
The Good News
This model gives us some useful design parameters. We can be purposeful in communicating and teaching so that we are sensitive to how our brains work.
Here are a few tips:
- Remove everything extraneous or that does not convey meaning-this often means visually removing something like a logo, but can also relate to things like music playing.
- Key ideas should be repeated and repeated consistently.
- Unattach yourself from research, detailed technical information, and context-strip your content down to key ideas for a specific user or audience. What do they need to know to use this? What can they take in?
- Do not use only one mode of input (this leads to overwhelm quickly), but convey meaning through text, visual elements, movement, audio, etc.
- When using multiple input modes, they should carefully orchestrate to create a single message (not add to extraneous load). For example, place the text for an image right next to that image.
**A note on source and research. CLT is based on the work of John Sweller ( Cognitive Load During Problem Solving: Effects on Learning. (1988). Cognitive Science. 12(2): 257–288) and is research that was conducted almost exclusively with Western, white bodies. Thus far in our practice, following design principles with cognitive load in mind has been beneficial, but we’d like to be transparent that the science behind it was not done equitably and cannot be said to be inclusive.
For Example: COUNT THE KICKS
The Count the Kicks app teaches women to count the kicks of their unborn child near the end of pregnancy to prevent stillbirth. Their materials needed to be appropriate for various audiences, languages, and literacies.
The true design challenge, however, became one of cognitive load. We could not afford to overload a mom, especially a mother from a high-risk group, and have her miss out on a simple act (counting kicks) that could save her baby’s life.
You can notice some of the changes we made:
To minimize extraneous load
- no bubble letters in the heading (hard to read)
- single color in headings
To support germane load
- Color blocks behind single ideas to help eyes group information
- images are for communication of the text immediately next to them (not just for interest or engagement)
- far less text overall
- list limited to three items
- illustrations leave room for a mom to see herself in them
To focus intrinsic load
- only the information relevant to a mother and her ability to take action
- no statistics, no long explanations, no frequently asked questions
I have a theory about the human mind. A brain is a lot like a computer. It will only take so many facts, and then it will go on overload and blow up.
— Erma Bombeck