Digital Avatars Can Now Fake a Realistic Heartbeat
Virtual faces that look alive — which could also fool identity checks.
Digital heads — lifelike 3D copies of a person's face that you can move, light and film from any angle — have gotten very convincing. But they've always missed one thing: a heartbeat. Real skin shifts color slightly with every pulse, and our eyes pick up on it even when we don't notice. Researchers at University College London and Meta built a system that adds that missing flicker back in.
The trick is that this isn't random flickering. The team recorded each person's real pulse with a contact sensor, then taught the avatar to reproduce that exact rhythm by nudging the color of the face's skin in every frame. In tests across 152 recordings, a computer analysing the rendered fake faces could read the heart rate back to within about one beat per minute — nearly perfect, and with no visible drop in image quality.
So what? On the upside, avatars in video calls, games and VR could finally feel like a person is actually there rather than a moving mask. That helps remote meetings, virtual doctors, digital actors, and tools that quietly check your health through a webcam. On the downside, banks, border agents and apps increasingly verify identity by asking you to look at a camera and confirming you are a living person. A face that convincingly simulates a pulse could help deepfakes slip past those checks.
There are real limits. This is a short research paper, not a product, and it only worked on people sitting still in controlled recordings with a physical pulse sensor attached for training. It needs per-person data and doesn't yet run live. Still, it is a clear signal: the line between a recorded human and a generated one is getting blurrier, and the tests we use to tell them apart need to keep up.
- The system copies the tiny skin-color changes your pulse makes and builds them into a 3D digital face, so the fake head appears to have a real heartbeat.
- Computers reading those rendered faces measured the heart rate within about one beat per minute — close enough to pass as a real person.
- Big upside for VR meetings, games and health apps; big risk that it helps deepfakes defeat the 'prove you're a real human' checks banks and governments use.
Why It Matters
More convincing digital humans for work and play — but also a new way to fool face-scanning identity checks.