If you were in a crowd of people and saw a family member in the crowd, you would automatically recognize their face and automatically feel an emotion towards the face.
This is because of the Fusiform Face Area or FFA is a part of the brain outside of the visual cortex.
It's only purpose is to recognize faces
It allows faces to go around the brain's usual interpretive channels.
We can recognize faces faster than objects.
The FFA is near the amygdala which is the brain's emotional center.
People with Autism don't use FFA when looking at faces. They use regular passages in the visual cortex and brain that are used to recognize and interpret objects but not faces.
Slide 2
Conclusion
People acknowledge faces on web pages quicker than all the other things on the page (except for those with Autism).
Faces looking directly at the viewer have the biggest emotional impact.
If a face on a web page looks at another spot on the page or product, people will also usually look at it. However, they may look at it but not truly see it.