137 Uncanny Valley

Both abstract and realistic depictions of human faces are appealing, but faces in between are not.

• When a face is very close but not identical to a healthy human—as with mannequins or computer-generated renderings of people—it is considered repulsive. This is the uncanny valley.

• The uncanny valley refers to human features generally, but uncanny faces are the key source of the revulsion.

• The response is likely due to evolved mechanisms for detecting and avoiding people who are sick or dead.

• Until robots, computer renderings, and mannequins are indistinguishable from humans, favor more abstract versus realistic depictions of faces. Negative reaction is more sensitive to motion than appearance, so be particularly cognizant of jerky or unnatural facial expressions and eye movements.

See Also Anthropomorphism • Attractiveness Bias Threat Detection • Top-Down Lighting Bias

Mannequins that are realistic—but not perfectly realistic—are considered repulsive, dwelling in the uncanny valley.