Researchers are experimenting with a new form of biometric security that could allow wireless earbuds to identify users through the subtle vibrations created by their heartbeat.

The experimental system, known as AccLock, uses motion sensors already built into many modern earbuds to detect tiny internal movements inside the ear canal. Rather than relying on fingerprints, facial recognition or voice analysis, the technology measures ballistocardiography signals generated as blood moves through the body.

These vibration patterns are considered highly individual, allowing the system to determine whether the person wearing the earbuds matches the authorised user.

According to researchers behind the project, the authentication process runs continuously in the background without requiring users to speak, tap controls or perform additional actions. The goal is to create a more passive security system that could eventually be used for unlocking devices, authorising payments or accessing connected smart home systems.

To improve accuracy, the team developed a deep-learning model capable of filtering out background noise and separating heartbeat signals from normal body movement.

In testing involving 33 participants, the prototype recorded false acceptance rates of 3.13 per cent and false rejection rates of 2.99 per cent.

The technology remains far from commercial deployment, however. Researchers found the system struggled when users were walking, talking or moving their heads, with motion significantly reducing accuracy.

The team also tested the software using Apple AirPods and reported the system remained operational despite hardware limitations.

Featured image: JBL Tune Flex 2