The Essential Role of Mental Models in HCI: Card, Moran and Newell

In the formative years of HCI in the early1980s, researchers explored the idea that users form mental models of computer systems which they use to guide their interaction with the system. This was a powerful concept because it meant that if we, as interface designers, understood what kind of model the user constructed as well as the process of constructing it, we could make computers easier to use by developing systems that were consistent with that model or that made it easier to construct the model.

In this brief essay I examine a concept of mental models put forward by Card, Moran and Newell (1983) in their book, The Psychology of Human-Computer Interaction, and explore its impact on the science and application of HCI. This book and subsequent papers had a strong and lasting influence on the field of HCI as an applied research discipline because it provided a testable theory that bridged the divide between psychological theories of human processing and the emerging discipline of interface design.

Our purpose in this book is to help lay a scientific foundation for an applied psychology concerned with the human users of interactive computer systems. Although modern cognitive psychology contains a wealth of knowledge of human behavior, it is not a simple matter to bring this knowledge to bear on the practical problems of design – to build an applied psychology that includes theory, data and methodology. (Card, Moran and Newell, 1983).