Today’s lecture covers the topic of ‘Mental Models’. This has been a long standing and influential idea in Human Computer Interaction. The basic idea is that people have internal mental models of the way a system works and they use these models to help them when they use a system. One possible application of this idea for designers is that by designing our systems so that the working of the system is clear in the interface, it is easier for users to form a useful mental model of the product.
Critical Questions
The idea of Mental Models is often appealing to designers because it seems to make sense and offer practical and useful insights into the way users interact with products. However, there are some critical questions you should consider also.
- Do people really have Mental Models? What separates a Mental Model from everyday knowledge?
- Focusing on mental representations can divert attention from the many other resources people use to help them when using interactive products. What about other people, or physical resources?
- How much does this actually help designers? Does it change the problem of design to the problem of uncovering the correct model?
Practical Task
Your task for this week is to see if you can find evidence for Mental Models in the way people use interactive products. In groups of two or three, decide on an interactive product to investigate. The product could be anything from a web-page, to a mobile phone, to an elevator. Find a user of this product and interview them to find out how they understand the system to work.
Ask the person to show you how they use the product. Ask them to explain what they are doing as they use it. Try stopping them from time to time and asking what the think the product will do (and why) before they make an action. Then when they take the action, ask them if the response of the product matches their expectations.
You should prepare a short (5-10 minutes) presentation of the results of your interview for next week’s class. It doesn’t need to be anything fancy, but you should try to make a diagram, picture, or short description that sums up what you think the person’s mental model was. If you don’t think the person had a mental model - that’s also a good result. You should show instead the other resources they used to help them interact with the product.
Slides
Lecture slides are available.
Readings
There are three readings for the topic of mental models. Copies of the first two will be handed out in class.
- Carroll, J and Olson, J. “Mental Models in Human-Computer Interaction” in Handbook of Human-Computer Interaction, M Helander (ed), Elsevier, 1988.
- Payne, S. “Users’ Mental Models: The Very Ideas” in HCI Models, Theories, and Frameworks, Carroll, J. (ed) Morgan Kaufmann, 2003.
- Norman, D. “The Psychology of Everyday Things”, Basic Books, 1988. Chapter 1.
Web Resources
A search on ‘mental models’ will turn up many articles, blog entries, etc. Here are three that I browsed and found informative:
- What’s Your Idea of a Mental Model - Article at ‘boxes and arrows’, a usability blog. Well written article with some interesting comments.
- Mental Models - Annotated list of resources on the topic.
- Wikipedia article - short, but it has links to related topics and researchers in the area that might be of use.