Grouping

In order to rapidly make sense of novel situations and interfaces, our minds will "smooth" things. It's important to note that this smoothing will override reality if reality is too difficult to comprehend. We don't like the unknown as it may contain threats, which in turn incur stress. So, a great deal of cognitive resources are devoted to decoding and understanding that which is in front of us at any given time.

Since this decoding can't take too long (our defensive mechanisms "demand" a response and attentional resources cannot be pointed at one thing for too long) our minds will actively engage in parsing scenes by grouping elements. We seek relationships where none may exist simply because it helps us to understand, and if we understand, we can formulate a response. A preattentive feature that can be used effectively to indicate grouping is similarity. This can be further broken down into text size, color, and shape. Items within a scene that share any of these characteristics are liable to be grouped preattentively, especially if they share proximity. A good example of this can be seen by looking up at the stars on a clear night- Orion. The three-star belt with the four-star extremity square seems to "pop" out at the eye. Why? The stars are roughly the same size, color, and intensity, and easily "form" a geometric shape.

The grouping instinct was demonstrated to me by my own mind a few years ago. I went to a library to conduct some research and approached a study table. No one was sitting there, but a crumpled paper bag from a bakery was on the table. Instinctively, I looked around for an owner; not seeing anyone that fit my definition of an owner, I sat down and immediately felt uncomfortable. A thought occurred to me- "Anyone looking at the table will assume the bag is mine, because it is close to me and because an inanimate object like this bag has to have an owner; it can't get around by itself". A few minutes later, a student came to the table, looked at the bag, and then looked at me.

I found it easy to believe that he had grouped me with the bag. He thought it was mine.

After a few more minutes, I saw that a computer station had opened up, and I decided to move. As I picked up my papers and bag, I watched the person who had joined me. He didn't look at me, but he did look at the crumpled bag.

I also found it easy to believe that he was now grouped with the bag.

Implications for information design are that users will group elements of your interface, whether those groupings are real or not, simply in an attempt to understand. Since this is the case, use color and shape carefully, as these can act as confirmational cues to a user-created group that may not reflect reality. This may in turn cause confusion and unsatisfactory experiences.