Consider this: A doll with human-like features still doesn't look as real as a live person - do you know why? A new study claims it's all in the eyes.
Researchers have found that a face has to be quite similar to a human face in order to appear alive, and that the cues are mainly in the eyes.
"There's something fundamentally important about seeing a face and knowing that the lights are on and someone is home," said Thalia Wheatley of Dartmouth College.
Wheatley and graduate student Christine Looser drove around New Hampshire visiting toy stores and taking pictures of dolls' faces.
They then paired each doll face with a similar-looking human face and used morphing software to blend the two, to make a whole set of intermediate pictures that were part human, part doll.
Looser and Wheatley found that the tipping point, where people determined the faces to be alive, was about two-thirds of the way along the continuum, closer to the human side than to the doll side.
Another experiment found that the eyes were the most important feature for determining life.
The results show that objects with faces may look human, but telling the difference lets us reserve our social energies for faces that are capable of thinking, feeling, and interacting with us.
"I think we all seek connections with others. When we recognize life in a face, Wheatley said, we think, "This is a mind I can connect with."
The study is published in Psychological Science.