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How Cognitive Fluency Affects User Behavior

Although you may have never heard the term “cognitive fluency” before, it influences the way that you evaluate information and make decisions every day. So what exactly is cognitive fluency, and how can you take advantage of it to create better designs for your customers?

What is Cognitive Fluency?

The term “cognitive fluency” (also known as processing fluency) refers to a user’s subjective experience of how easy or difficult it is to process and complete a mental task. Importantly, it does not signify anything about how difficult the task actually is-only about how difficult users perceive the task to be, and the feelings they associate with it.

How Does Cognitive Fluency Work?

Cognitive fluency is at work, even subconsciously, any time that we are in a situation weighing information and deliberating between different options. Its impact on our choices and decision-making process is just as influential as our rational, conscious thoughts.

Products with high cognitive fluency often have higher conversion rates, and help people become more comfortable with using them. Designs that are simple, straightforward, and even minimalistic are easier for people to process. For example, if all of a website’s elements are in the expected place, with a header at the top of the page and a navigation bar on the left-hand side, then users have an easier time navigating the site and completing their desired tasks.

The concept of cognitive fluency has its roots in several well-established psychological principles. This explains why, for example, users will view products with designs that are difficult to read or interpret as overly complex.

In one study by psychologists Hyunjin Song and Norbert Schwarz, researchers presented students with a paper that described a workout routine or a recipe for preparing sushi. The texts were written in a font that was either easy to read or difficult to read. Students who received the text in the easily legible font believed that the instructions were easier to follow than those who received the text in the complicated font.

Another relevant psychological phenomenon for cognitive fluency is the mere exposure effect, also known as the familiarity principle. We perceive things that are familiar to us more positively, whether it’s a song we keep hearing on the radio or a stranger we see on the street every day. This suggests that people will view designs that are familiar more positively, and also explains why users react so negatively whenever their favorite website undergoes a fresh redesign.

What Role Does Cognitive Fluency Play in Design?

Many aspects of design can impact cognitive fluency, i.e. how much mental effort users feel they are expending on a task. Relevant design factors include:

  • The style and size of fonts
  • Color contrast between text and background
  • Word choice and terminology

In general, anything that impacts people’s feelings about how easy it is to perform a mental task can—and does—affect their judgments and decisions.

This is why, for example, many websites these days seem to have a similar look and feel. Users will judge sites with familiar designs as easier to use and navigate.

What Challenges Do Designers Face with Cognitive Fluency?

One challenge for designers in terms of cognitive fluency is not getting too attached to your work. As you spend more and more time creating a design, you become more familiar with it and your brain creates a sense of cognitive fluency, causing you to view it more positively. This is why it’s usually a good idea to get a second opinion on your designs from someone with a fresh set of eyes.

Cognitive fluency can work in interesting ways: it’s not always about how clean and simple the design is, but how easy and familiar users judge it to be. Here at Very, for example, we had a client working in the biomedical engineering space that needed us to create a research portal. After doing user research, we realized quickly that the site shouldn’t be too flashy or pretty in its design.

These users were familiar with the cluttered, “ugly” appearance of many websites in academia that have been built by non-designers. Seeing information presented in a design that was too “beautiful” made them more suspicious and more likely to bounce away from the site.

Another classic example of cognitive fluency gone wrong is the e-commerce retailer Woot, which offers cheap deals on a variety of products. The website initially had a very basic, straightforward design that users had grown accustomed to navigating.

When the company redesigned its website several years ago to be sleeker and more elegant, many users stopped visiting the site. The previous bare-bones appearance of the Woot website actually made shoppers feel as though they were getting a better deal on the products they bought, as though it were a virtual “flea market.”

Final Thoughts

The key takeaway from this concept of cognitive fluency, first and foremost, should be to know your audience. Don’t try to reinvent the wheel by doing something that’s too new or too different for them, and don’t get swept away by the latest trendy designs. Look at the work through your customers’ eyes, and build a final product that will be cognitively fluent for them to use.

If you’re looking to gain from a partner to help guide through UX design, we’re always here to help.

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