Pre-Attentive-Attributes are used in data visualization to focus the readers view quickly on the most important point of information. It is achieved by modifying the appearance of that point of information, so that it sticks out in some way from the rest of the data. The effect is that the brain will catch the difference subconsciously and give that point direct attention.
There are four main categories of Pre-Attentive Attributes that determine the kind of difference of the attribute. These categories are Color, Form, Spacial position and Movement.
There are two different possibilities to use color as an Pre-Attentive Attribute: Hue and Intensity.
Changing the form gives the most possibilities to catch the attention of the reader. Here are the most common effects:
Also positioning the information in special ways can be used as a Pre-Attentive Attribute. Here are two examples:
At last there is the possibility to use movement in some sort of animation to catch the reader’s attention.