The pair recorded how cells in a region of the brain devoted to facial recognition, called the fusiform face area, code the information.

ECONOMIST: Facial characteristics

That's an area of the brain associated with identifying negative facial expressions, unhappiness or neutrality.

CNN: When a woman doesn't want sex

One technological area that Google appears to be holding back on for now because of privacy concerns is facial recognition to identify strangers.

FORBES: Google's Privacy Director Is Stepping Down