Figure-ground relationship is the design principle that any element is perceived either as an object of focus (figure) or as something else (ground). This is one of the Gestalt principles of perception, where perception focuses on a central element and others become undifferentiated in the background. This is true of other senses as well as vision (e.g., when you hear your name in a crowded party your focus switches from your current conversation to listening to another).
An unstable figure-ground relationship is the source of many visual illusions and tricks (see above), causing ambiguity in interpretation as the focus switches between different elements. When the relationship is stable and figure and ground are clearly defined, the figure element receives more attention and is easier to remember.
Certain visual cues help determine which elements are figure and which are ground:
- figures have a clear shape, while (back)ground is shapeless
- ground continues behind figures
- figures generally appear closer in space with an identifiable location, while ground is farther away with no clear location
- elements below the horizon are more likely to be perceived as figures, and above the horizon are more likely to be ground
- elements in the lower parts of a design are more likely to be perceived as figures, and higher are more likely to be perceived as ground
Designers can focus users attention and minimise confusion by clearly differentiating figure and ground, and ensuring that the relationship between them is stable by using these visual cues. Elements that are clearly perceived as figures have a higher probability of recall from memory.
Universal Principles of Design by Lidwell, Holden & Butler