Emphasis
Emphasis is also called Focal Point or Dominance.
The object being emphasized should grab the user's attention immediately and make them want to look further.
Our eye is drawn first and foremost to images of faces, and you need to be careful that the pull towards the face is not so great that the viewer's eye does not take in the rest of the design.
Color, contrast, size and directional devices also work to emphasis a particular element of the design.