Uncanny Valley: Will We Ever Learn to Live with Artificial Humans?

Sept. 17, 2011— -- A new member recently joined the Japanese band AKB48. Pop blogs and a magazine cover story introduced Aimi Eguchi as a sweet 16-year-old from a Tokyo suburb. But there was something strange about this new girl.

Her incandescent looks and sterling voice won Aimi instant attention and the center spot in a candy ad. Yet questions arose when she appeared in two video spots. Aimi seemed stiff and awkward – not uncomfortable, more like unnatural.

"There was a weird reaction to it," says Zac Bentz, a writer and reviewer for the online music store HearJapan.com. "Within a week or two, people were already saying, 'Well, this doesn't look right.' "

She always looked straight at the camera, shared a bizarre resemblance to other girls in the band, and had a peculiar beauty. Unsettled fans pestered the group, trying to figure out more about this girl, but she never appeared in public.

After a few weeks, AKB48 admitted that Aimi was computer generated. They took the nose, eyebrows, hair, and lips of six band mates and digitally stitched them into a new singer. (Watch a video of Aimi here. )

Fans had unwittingly tumbled into the "Uncanny Valley," the idea that people feel uneasy about things that appear nearly human but actually aren't real. While Americans often associate the phenomenon with animated movies, Japan has increasingly pushed the bounds in the music world. Aimi is not the first computer-animated character to chase pop stardom, and many assume "she" will not be the last.

"It was the next step in a long history of fabricating singers," says Mr. Bentz. The movement "is very Japancentric still, but it is a huge, huge thing over there."

Mapping the Uncanny Valley

While animators try to climb out of the Uncanny Valley, researchers still struggle to understand the science behind it. The term is now 40 years old, yet its existence remains mostly anecdotal, says Ayse Pinar Saygin, who this summer carried the field a strong step forward. The professor of cognitive science at the University of California, San Diego, led an international team of researchers that discovered that brains perceive humans and impostors in very different ways.

The team wanted to see how subjects would react to Repliee Q2, one of the most realistic androids in the world (pictured above) . At certain angles, the machine could easily be mistaken for a Japanese woman. Once it starts moving, however, the illusion is shattered. Repliee has perhaps the most sophisticated set of motors and joints in an android to date. Yet it's still obviously a machine.

But forget conscious-level observations – Dr. Saygin wanted to peer deeper. She had subjects get into a London-based functional magnetic resonance imaging machine, which can track brain activity. Once inside, they watched 12 videos of Repliee performing simple tasks, such as nodding, waving, sipping water, and picking up objects from a table. The subjects then watched the same actions performed by a real woman – in fact the researcher whom Repliee is based on. Finally, they saw a third round of videos, this time starring Repliee with its skin removed to reveal the machine underneath.

The metallic robot and the real woman triggered very similar results. The woman sparked more neural activity, but it mostly occurred in the same regions of the brain.