Michael Gearon

Mental Models

Michael Gearon

Mental models is not a new term, it was talked about long before we talked about user experience and human-computer interaction. The idea of mental models was first talked about by Scottish psychologist Kenneth Craik in 1943 when he wrote the book The Nature of Explanation. Kenneth described mental models as “people carry in their minds a small-scale model of how the world works”.

Mental models helps form designs and patterns within products and services because it highlights the need for consistency and similarity. A silly but obvious example of this is that if a website navigation bar was only at the bottom of a web page that would go against expectations of the navigation being at the top of the page.

What is meant by mental models?

A mental model is how someone assumes how something should work. A mental model is based on past experiences, beliefs and perceptions. The purpose of these models is that rather than a person learning each time how something works we create shortcuts, reducing the cognitive effort it takes to navigate around something. With these shortcuts and assumptions people base their predictions about the system works and plan their actions based on that.

However mental models are flawed as someone may not have a complete understanding of all facts. In that way, a mental model is something that changes over time and differs between person to person and between different cultures and countries.

Mismatch and misaligned mental models

When we design services and products there can be cases where what has been designed is not what the user is expecting, this misalignment can lead to mistakes and confusion when using the interface.

There are a few options to overcome this mismatch issue. You could change the interface to conform to the user expectations of how it should work. This is the simplest way to align your interface and solve the error.

The next option is to purposely stick with the design choice, it it the riskiest choice but if there is good evidence to demonstrate what has been designed is a better solution it could make sense to leave it as is. However, you need to allow for time to adjust and give the users choice when making the switch. For example, large scale organisations and companies often notify their users of upcoming changes with the option to switch to the new design, then the new design is rolled out to everyone by default but with the option to switch back to the old design, and then over time the switch is removed.

Discovering mental models

To understand how users perceive a service or product you need to do research. This could be done through user interviews, card sorting and other forms of workshops. You could also do competitor research, this is particularly useful if you are limited by budget or time but does come with consequences of not knowing how effective what they’ve done has been.

As part of the process you may also test wireframes and prototypes to see how the user is interacting with the product, asking them to think out loud as they navigate that system.

By going through these steps you avoid putting effort, time and money into building something fully that is not usable.

Key points

  • Mental models are how people perceive the world around them, based on their own experiences and beliefs
  • People use these models to make shortcuts and make assumptions on how systems work and base their actions on what they believe is the correct way to navigate through that system
  • In most circumstances it is best to design the system on what users perceive to be the correct way. We can discover this through user research and testing ideas and assumptions
  • Where you change the pattern it is recommended to give the user choice, extra guidance and help to shape their new model and understanding of that system
Michael Gearon

Written by

Michael Gearon

Senior Interaction Designer and Co-Author to Tiny CSS Projects