Illustration by Ran Liu

Product design is a powerful medium to create engaging products and services. Designers use different tools to understand how the user thinks and behaves when introduced to a product, and in particular, UX designers are expected to predict how users will interact with (or experience) a product, service, or website.

One way UX designers can do this is by tapping into their users’ prior knowledge. Prior knowledge affects how we interact with new objects and applications in a meaningful way. While it is true that most people have both a differing set of abilities and their own specific prior knowledge that make every user unique and different, designers can’t design different versions of the experiences to fit every specific user.

Designers can gain an understanding of how people interact with a product by referencing mental models. Mental models are one of the most valuable concepts in human-computer interaction.

What is a mental model?

Our prior knowledge exists as mental models, or the patterns and behaviors we expect when encountering an interaction or experience that’s similar to one (or more) from our past. Basically, prior knowledge and experiences influence a person’s reaction to what they see, what they hear, and what they feel. They help shape actions and behavior, influence what people pay attention to in complicated situations, and define how people approach and solve problems.

A mental model represents a person’s thought process for how something works. The tricky part is that mental models can be based on incomplete facts, past experiences, and even intuitive perceptions. In addition, mental models tend to differ between countries and cultures.

In UX design, mental models can help designers understand and analyze problems in their designs through user testing. If many people make similar mistakes or missteps, one reason could be a designer’s misunderstanding or misinterpretation of a mental model.

Mixed mental models can cause confusion and frustration.
Mixed mental models can cause confusion and frustration. Image credit Adobe Stock.

Mixed-up mental models

Confused mental models happen when users fail to recognize key differences between similar parts of a system. Mixed-up mental models can also affect discoverability of information within a product or application.

One familiar example of a confused mental model is the Google search engine search feature. Some users are unable to distinguish between the search field on and the URL entry field in a browser. Users will often search for the name of a well-known website and then click the link rather than simply entering a site’s URL (even without the “www” and “.com” wrapping) in the URL bar.

A study by Nielsen offers a series of common mental model confusions that some users appear to encounter on a regular basis:

  • Browser commands and commands that are held within an app
  • Local and remote information
  • Login options and passwords
  • Windows provided inside an operating system and those inside a browser
  • Windows and applications
  • Icons and applications

How to improve misaligned mental models

UX designers can use usability testing and UX research methodologies to help prevent misaligned mental models. Designers can also focus on interactive tours, careful onboarding, and real-time feedback to improve misaligned mental models.

When considering examples of mental models, one to note is from the aforementioned search and ad giant. Google is, as most people know, the most used web search engine in history. The company has also been building high-quality applications for more than a decade, and they are renowned for delivering an outstanding user experience. But Google failed to deliver that best-in-class experience when they refreshed the look of their calendar application back in 2017.

Google new calendar interface in 2017 changed the mental model for users.
Google new calendar interface in 2017 changed the mental model for users. Image credit Tech Crunch.

Google made a few significant changes to its calendar interface, forcing users to adapt to both a new design and a new mental model. The results and feedback did not go well, and the changes were not well received. Fortunately, Google allowed users to switch between the original and newly designed versions, and eventually, they reverted to their original design after collecting user feedback.

Designers should always strive to improve their designs while continuing to keep them in line with existing mental models. It is better to create prototype designs and conduct beta testing to understand whether a new solution empowers or misaligns an existing mental models before launch.

How mental models can be applied to UX

A designer’s job is to ensure their designs meet both the user’s needs and fit their mental model and expectations. Designers can reference a few UX design best practices to help:

Jakob’s Law

Jakob’s Law states that because users spend most of their time on other sites, they expect your site to work in the same way as other sites they’ve already visited. In order to do this, designers should design with patterns users are accustomed to using.

Card sorting

Card sorting exercises can be a very useful technique in determining how your users categorize the information that will appear in your design. UX designers and researchers can conduct open card sorting where participants are given a deck of cards and ask them to group in a way which is meaningful to them. UX designers can also use closed card sorting to verify a pre-defined information architecture. Designers and researchers can ask questions about the groupings to get a clearer understanding of how the participants think.

Natural user interface

In design, natural user interface (NUI) is effectively an invisible user interface that remains unseen as the user continuously learns increasingly complex interactions. Natural user interfaces give the sense of instant accomplishment to the user. A NUI should fit the user’s context if the design is going to feel natural to them.  One example of a NUI is when a user swipes between home screen pages on a device running Google’s Android or Apple’s iOS operating systems. It feels natural to swipe between these screens because it mimics flipping pages in a paper book. When designing for NUIs, pay attention to the following: 

  • Convey instant expertise to take advantage of the user’s existing skills.
  • Use progressive disclosure to lay out a clear learning path to the users, one that allows them to start with basic skills and move on to something more advanced in small increments.
  • Create direct interaction through the direct correlation between user action and natural user interface reaction.
  • Limit the cognitive load.

Natural user interfaces are not a new trend in UX design. Companies such as Apple have been using natural design to improve customer engagement and to create real-world-like objects to connect with the emotions of the user. UX designers can use the same technique to create elements and interactions that help users feel comfortable when interacting with an application.

Designers have to focus on their conceptual models to identify what their users need while designers get a proper understanding of mental models through the synthesis of research.
Designers have to focus on their conceptual models to identify what their users need while designers get a proper understanding of mental models through the synthesis of research. Image credit medium.

Final thoughts for UX designers

In the context of UX design, mental models are what the user believes about how the user experience works. Mental models are constructed in a user’s brain and are based on what they know from past interactions with other products, sites, and applications. Learning about UX mental models and how to use them (often in addition to or in place of our own) can help UX designers develop designs that make sense to users and create an experience that’s intuitive and easy to follow.