Sunday, March 22, 2009

ID FMP: Model of Interaction

There are many theories that attempt to describe the cognitive processes that govern users’ interactions with products systems. Here I will focus on a model developed by Don Norman, which was outlined in his book Design of Everyday Things. This framework breaks down the process of interaction between a human and a product into seven distinct phases.

Seven Phases of Interaction with a Product System
  1. Forming the goal
  2. Forming the intention
  3. Specifying an action
  4. Executing the action
  5. Perceiving the state of the world
  6. Interpreting the state of the world
  7. Evaluating the outcome
Two important concepts related to Norman’s Theory of Action are the gulf of execution and evaluation. The gulf of execution refers to the gap between how the user wants to act and how the system allows the user to take action. The gulf of evaluation corresponds to the gap between how the system displays data to how the user interprets this data into knowledge.

Now let’s put this theory into context with some of the concepts and models that we’ve encountered thus far. First, I want to point out that this model aligns with Don Norman’s model regarding the relationship between a designer’s conceptual model and a user’s mental model [read more here]. The focus of this framework is the interaction between the system image, the product’s interface where user interaction happens, and the user’s mental model, the user’s understanding of how the product works which governs the user’s interpretation, evaluation, goals, intention, action specification.

I’ve extended Norman’s original model to account for the reflective cognition that is also involved in peoples’ interactions with products. Reflective cognition governs peoples’ higher-level evaluations, goals and intentions that ultimately drive peoples’ experiential cognition activities. Experiential cognition governs the second-by-second evaluations, goals, and intentions involved in peoples’ interactions with products. These two different modes of cognition are explored in greater detail here.

Here is an example to distinguish and highlight the interdependencies between these two different types of cognition and interaction. Let’s consider a person’s interaction with a car. In this scenario, a person’s reflective cognitive would include setting a goal such as choosing a destination and desired time of arrival, and evaluating what route to take based on understanding of current location and traffic patterns. These activities would govern a person’s experiential interactions with a car and drive their moment-by-moment evaluations, and creation of goals and intentions. Experiential interactions would include using the steering wheel to turn a corner or switch lanes, pressing the accelerator to speed up, and stepping on the breaks to stop the car.

How does the concept of mental models relate to this framework? The mental model itself is not represented by a single phase, or grouping of phases. It refers to the understanding that a user has of how a system works. Norman’s model was developed to describe how users interact with product systems on an experiential, minute-by-minute basis. At this level of interaction a user’s mental model drives their interpretations, evaluations, setting of goals and intentions, and specification of actions.

Now let’s explore how the different cognitive types come into play during the various phases of interaction. These cognitive types have been outlined in greater detail here.
  • Attention supports all phases of interaction from perception through to action execution. This cognitive process refers to a user’s ability to focus on both external phenomena and internal thoughts.
  • Perception is clearly called out as its own phase in Don Norman’s model.
  • Memory plays an important role during all phases from interpretation through to action specification.
  • Language supports communication throughout all phases of a person’s interaction with a product. Here I refer to both verbal and visual languages.
  • Learning enables people to use new products and increase effectiveness and efficiency in their interactions with existing products. This cognitive process supports all phases between the interpretation and action specification.
  • Higher reason governs all activities related to the setting of high-level goals and intent, and driving evaluations.
[source: Interaction Design: Beyond Human-Computer Interaction; and Don Norman's Book The Design of Everyday Things]

** What the hell is ID FMP? **

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