Simple Guide to Understanding User Interface Design Rules [Paperback]

Designing with the Mind in Mind occupies a unique position in design literature, being neither a compendium of rules (do this, don't do that), nor a deeply detailed treatment of cognitive psychology. Instead, it offers accessible explanations of how the human brain affects our perceptions and behaviors, and then shows how these descriptions serve as the motivation for basic design principles.

Jeff Johnson's earlier books are more comprehensive on the design side (GUI Bloopers 2.0; Web Bloopers), but the present volume offers the reader deeper insight into the implications of a more modest sub-set of design principles. He uses bite-sized chapters and clear language to provide the psychological and biological background, often including fascinating research results. The examples he uses to illustrate his points are both compelling and accessible. (And politically correct: both Apple and Microsoft get some thumbs-down ratings.) The sections where he translates psychological observations into "computer jargon" are useful for engineers.

The droll headings and examples keep things lively. "Reading Is Unnatural;" "Our Attention Is Limited; Our Memory Is Imperfect": this sums up how I feel sometimes. I learned that the gap between what a user wants and what a user gets is called the "gulf of execution." And the usability test participant's comment, "I'm in a hurry, so I'll do it the long way." is priceless, as is the explanation: "Avoiding thought when using computers is important." (The participant suspected there might be a faster way to perform a task, but didn't want to take the time and effort to figure it out.)

Readers who implement user interfaces but don't have a background in cognitive psychology, or who have that background but might not know how to apply it to the world of user interface design, will get a lot out of this volume. Those who exist with one foot in each world will also enjoy it.

Developed from a course titled "Human-Computer Interaction" that he taught at the University of Canterbury in New Zealand, Dr. Jeff Johnson -- who holds degrees from Yale and Stanford, experience at Xerox and author of the book, "GUI Bloopers" -- offers contextual explanations as to how we visualize and categorize information, data and images in such a manner that engineers and programmers can design user interfaces in the most effective manner. It's a well-written, insightful and very practical guide that will be of interest to anyone interested in the how-and-why of computer/machine interface design.

Topics covered include:

How our visual perceptions are biased by experience, the current context, and user's intentions/goals;

How our vision is optimized to see structure; Gestalt principles of proximity, continuity, closure, symmetry, figure/ground separation and then how they are combined;

How structure enhances people's ability to scan long numbers; how visual hierarchy enables readers to focus on the most relevant information;

A discussion of psychological theory that indicates than we're "wired for language, but not for reading" and the design implications of these findings;

Limitations of our color vision and implications for how color is presented in user interfaces; the fact that user's peripheral vision is poor and common methods used to makes messages more visible (e.g. pop-ups, sound, and flash/motion);

Design implications regarding our limited short term and long term memory; how recognition and learning from experience for readers is typically easy while problem solving and recall is hard;

And, a discussion of time requirements for systems designers to consider.

Written in an easy-to-understand narrative, lecture-format with dozens of illustrations in each chapter, readers will find this book to be a delightful and welcome primer detailing the fundamental psychological principles behind effective design rules.

Highly recommended for college and university library collections as well as graphic designers and psychologists interested in human/machine interface design.

R. Neil Scott
Middle Tennessee State University

This concise book by J. Johnson is filled with practical guidelines and rules of thumb for would-be designers of software-intensive, multi-function tools. Such e-tools' success requires an interface that creates direct, low-friction paths from the goals of the tool-user to the goal-promoting operations made possible by the tool, whether it be a word processor, a smartphone, or an MP3 player.

Whenever one specifies a guideline or rule of thumb, or announces a policy that is about to be adopted and enforced, it is wise to explain the reasoning behind it, even if one has the power to enforce its adoption. Detailing the reasons, in tandem with examples of good and bad practice, makes the rule more memorable, and more likely to be reconstructed by someone trying to recall what the rule is. The reasoning, if valid, will also undercut the natural tendency to ignore or actively subvert rules that appear arbitrary, with no better basis than the whim of some over-controlling personality.

An incredible thing about "Designing with the mind in mind" is that most of its guidelines are ultimately easy to remember and, equally important, "easy to swallow", that is, made as palatable as possible by the reasons and examples provided. Because the basis for each guideline is so well explained, the guidelines all make intuitive sense.

The reasons provided for the design guidelines are primarily drawn from cognitive psychology, and secondarily from neuroscience. Therefore, the title appropriately reads "with the mind in mind" and not "with the brain in mind". In a compact book (around 200 pages) that can be read in two sessions, it would have been a mistake to try to ground all the guidelines in neural constraints. Far better is the strategy followed by Johnson, who roots the guidelines in "hard" cognitive psychological constraints that, in turn, one could explain in terms of brain circuitry -- but only if given a budget of another 200 pages. In a few cases, Johnson does sketch neural explanations, in order to exemplify how each mental constraint could be related to a handful of pertinent neural constraints. But, just as one of his interface design principles is to avoid forcing the user to learn geek-speak that is irrelevant to the user's goals, Johnson makes no attempt to give more than short glimpses of the arcane objects and vocabularies found in modern neuroscience.

Another welcome aspect of the book is the way that each chapter builds on the main themes of earlier chapters. For that reason, but also for the overarching perspectives they offer, the last two chapters are the best. One explains how design can maximize the ease with which users explore and learn to deploy the full range of nifty functions made possible by a software-intensive, multi-function tool. The other explains how the time scales of tool operations (such as feedback that a mouse click has been received) must mesh with the time scales of the mind's operations. Poor temporal meshing between these two contributors to the person-machine "conversation" (Johnson's apt term) leads to many gratuitous frustrations and annoyances, which will drive users to abandon the offending product X in favor of a product Y that meshes better with the time scales of mental operations. This will happen even if X outperforms Y on many other, "objective", benchmarks.

Many of the topics treated in the book have been treated elsewhere, notably in prior design books by authors familiar with cognitive psychology, but the approach taken here is remarkable for its elegance and conciseness. Anyone in the business of designing a software product that is complex enough to have an associated "learning curve" will find here many good ideas for minimizing the curve's steepness. The book's own learning curve is very gentle, despite the wealth of ideas.