How to Put Cognition to Work in Design — and the Quiet Persuasion of Affordance
We look at what the three cognitive processes of selective attention, association, and mental models mean for actual design, and go on to examine affordance — the concept that guides user behavior through the unconscious.
In the previous post, we looked at three cognitive processes that play a central role in how humans form experience — selective attention, association, and mental models. Each operates at a different stage: selective attention at the entry point where information is received, association in the process of organizing it, and mental models in the stage of interpreting and putting it to use. Now let’s look at what these mean for actual design, and follow that thread through to the concept of affordance, which extends naturally from it.
The Challenge Selective Attention Leaves for Design
When it comes to selective attention, designers need to consider two dimensions.
One is quantitative: using visibility and contrast, designers must give core information enough visual distinction — proportional to its priority — that it wins the user’s selective attention. The other is qualitative: designers must deeply understand what the user is interested in and curious about, so that their attention is drawn there naturally.
What designers should especially guard against here is the complacent assumption that laying out information without much thought, or simply packing in as much of it as possible, will lead users to receive all of it as useful and meaningful. As we saw earlier, human attention is selective, so presenting everything with equal weight amounts to showing nothing properly at all. Information must be rigorously leveled, and the closer a piece of core information sits to the intended experience, the more sharply and compellingly it should be placed in front of the user.
Association and the Hierarchy of Information
Next, association offers an important insight into how information should be organized and layered.
The information designers want to convey to users must be organized so that it is semantically related, allowing users to naturally chunk it together for processing. Because human short-term processing capacity is limited, information needs to be layered appropriately so that too much of it doesn’t pour in at once. As noted earlier in the discussion of selective attention, information placed without much thought not only fails to catch the user’s eye — from the standpoint of association, it also drives up cognitive load excessively, actively hindering the processing and uptake of information rather than helping it.
Designers must therefore examine closely both the meaning of each piece of information and how pieces relate to one another. One more thing to watch for here: designers must verify that the relationships they’ve established actually hold from the user’s point of view as well. Information that seems obviously grouped to the designer may be classified by an entirely different logic in the user’s mind. Which pieces of information a user perceives as related can vary considerably depending on that user’s experience and context.
Because the standard of relatedness shifts with the user’s experience and context in this way, association is closely tied to “convenience,” one of the UX design parameters covered elsewhere in this series.
Mental Models and Reducing the Cost of Learning
Finally, of the three cognitive processes, the mental model is the concept most frequently invoked and most highly valued in UX design. The reason is that it serves as an especially powerful and efficient means of guiding the user’s experience.
In practice, it is close to impossible for the maker of a product or service to explain, one by one, the design intent and how to use every single feature. And even if that were possible, if learning it demands significant time and effort, it becomes a heavy burden for the user — one that can drive them away from the product altogether.
Minimizing this learning cost is therefore one of the central tasks of UX design, and this is exactly where the mental models users already carry come into their own. When a design makes good use of the informational structures a user has already built up, that user can grasp intuitively how the product works without any separate explanation. This is precisely why a single, well-placed icon can be more useful and more powerful than a lengthy user tutorial, and why it can guide a user’s action naturally and intuitively.
New Experience Guided by Past Experience
This quality of naturally drawing out a user’s action through a mental model is called affordance, and the concept deserves a closer look.
To begin with, affordance is clearly different in character from explicit guidance — a difference already implicit in the term itself. Where guidance tells the user outright, “Press this,” affordance instead leads the user to feel, on their own, “I should press this.”
Looking at the word’s etymology makes this difference even clearer. The English verb “afford” roughly means “to be worth doing” or “to have the capacity for.” In that spirit, affordance doesn’t force or command — it quietly and naturally leads a person toward an action that is, in a sense, already within their reach.
We noted earlier that “behavior,” unlike conscious “action,” is a representation that manifests unconsciously. That distinction is exactly what affordance draws on — it operates on behavior, not action, which is why it works beneath the level of conscious deliberation.
This implies that guidance through a mental model doesn’t arise from a user’s conscious judgment but occurs naturally within the realm of the unconscious. In other words, faced with a design that has good affordance, a user doesn’t consciously wonder, “How do I use this?” — instead, their hand moves in the right direction before they even realize it.
The major cognitive processes we’ve examined so far — selective attention, association, and mental models — all point in a single direction: they show us how to understand the user, and how to structure a design so that it genuinely improves the user’s experience.
To summarize: we must first deeply understand where a user’s interest and curiosity lie, and what shape the semantic relationships and mental models they already hold take. Only then can we predict what a user will focus on and what they will ignore, which pieces of information they will perceive as a single chunk, and what functions they will expect from a given form.
Building on that understanding, we must carefully classify and level information into a clear order of priority, arranging it with an eye not only to the user’s interests but also to their physical and cognitive limits. And ultimately, we should aim for designs that guide behavior naturally through the user’s unconscious rather than through explicit instruction. All of this, in the end, starts from the same place: we must study the user and the information deeply, and design the experience on top of that understanding.
The next post turns to the outward clue that this cognition leaves behind: “Behavior.” The behavior a user displays is, after all, the thread that lets us read the cognition underneath it.