Norman’s three levels of cognitive processing are
- visceral—The most immediate level of processing, in which we react to visual and other sensory aspects of a product that we can perceive before significant interaction occurs. Visceral processing helps us make rapid decisions about what is good, bad, safe, or dangerous. It is this level of processing—or something quite similar to it—that author Malcolm Gladwell discusses in his latest book, Blink.
- behavioral—The middle level of processing that lets us manage simple, everyday behaviors, which according to Norman, constitute the majority of human activity. Norman states—probably rightly so—that, historically, interaction design and usability practices have primarily addressed this level of cognitive processing. Behavioral processing can enhance or inhibit both lower-level visceral reactions and higher-level reflective responses, and conversely, both visceral and reflective processing can enhance or inhibit behavioral processing.
- reflective—The least immediate level of processing, which involves conscious consideration and reflection on past experiences. Reflective processing can enhance or inhibit behavioral processing, but has no direct access to visceral reactions. This level of cognitive processing is accessible only via memory, not through direct interaction or perception. The most interesting aspect of reflective processing as it relates to design is that, through reflection, we are able to integrate our experiences with designed artifacts into our broader life experiences and, over time, associate meaning and value with the artifacts themselves.
In the first three chapters of Emotional Design, Norman presents his three-level theory of cognitive processing and discusses its potential importance to design. However, Emotional Design does not suggest a method for systematically integrating Norman’s insightful model of cognition and affect into the practice of user experience design. It is my hope, in the remainder of this article, to
- suggest some deeper implications of Norman’s ideas for the design of user experience
- provide a method by which UX professionals can incorporate his ideas into a way of developing a richer understanding of users
- show how UX professionals might begin applying his ideas to the design of products
Designing for Visceral Response
What does it mean to design in a manner that takes advantage of what we know about visceral processing? Designing for the visceral level means designing what the senses initially perceive, before any deeper involvement with a product or artifact occurs. For most of us working in user experience, that primarily means designing visual appearance and motion, though sound can also play a role—think of the now classic Mac power-up chord. Those of us designing devices may design for tactile sensations as well.
A misconception often arises when discussing visceral-level design: that designing for visceral response is about designing beautiful things. Battlefield software and radiation-therapy systems are just two examples where designing for beauty may not be the proper focus. Visceral design is actually about designing for affect—that is, eliciting the appropriate psychological or emotional response for a particular context—rather than for aesthetics alone. Beauty—and the feelings of transcendence and pleasure it evokes—is really only a small part of the possible affective design palette. For example, an MP3 player and an online banking system require very different affects. We can learn a great deal about affect from architecture, the cinema and stage, and industrial design. Affective aspects of design deserve further attention and offer great opportunities for analysis from a holistic, UX perspective.
However, in the world of consumer products and services, where many of us work, attractive user interfaces are often appropriate. Interestingly, usability researchers  have demonstrated that users initially judge attractive interfaces to be more usable, and that this belief often persists long after a user has gained sufficient experience with an interface to have direct evidence to the contrary. Perhaps the reason for this is that users, encouraged by perceived ease of use, make a greater effort to learn what may be a challenging interface and are then unwilling to consider their investment ill spent. For the scrupulous designer, this means that, when a user interface promises ease of use at the visceral level—or whatever else the visceral promise of an interaction may be—it should then be sure to deliver on that promise at the behavioral level.
Designing for Behavior, or Interaction
Designing for the behavioral level means designing product behaviors that complement a user’s own behaviors, implicit assumptions, and mental models. Of the three levels of design Norman contemplates, behavioral design is perhaps the most familiar to UX professionals, especially those working within the spheres of interaction design and usability.
One intriguing aspect of Norman’s three-level model as it relates to behavioral, or interaction, design is his assertion that behavioral processing, uniquely among his three levels, has direct influence upon and is influenced directly by both of the other two levels of processing. This would seem to imply that the day-to-day behavioral aspects of interaction design should be the primary focus of our design efforts, with visceral and reflective considerations playing a supporting role. Getting behavioral design right—assuming that we also pay adequate attention to the other levels—provides our greatest opportunity for positively influencing the way users construct their experience with products.
Not following this line of reasoning can lead to the problem of users’ initial impressions being out of sync with reality. Also, it is difficult to imagine designing for reflective meaning in memory without a solid purpose and set of behaviors in place for the here and now. The user experience of a product or artifact, therefore, should ideally harmonize elements of visceral design and reflective design with a focus on behavioral design.