Temporary tattoos capable of reading thoughts: no, this is not science fiction, but a technological breakthrough born in an American laboratory. These electronic tattoos, designed to record brain activity, promise major advancements in neurology.
Left: Conventional EEG cap and electrodes.
Right: Printed electronic tattoo sensors connected to a conventional EEG reader.
Electroencephalography (EEG), a key method for diagnosing disorders such as epilepsy or brain injuries, traditionally relies on electrodes connected by wires to a headset. This cumbersome setup requires lengthy and meticulous installation, often uncomfortable for patients.
To address this, researchers at the University of Texas at Austin developed a biocompatible ink that penetrates hair to reach the scalp. This conductive polymer is applied with a digitally controlled inkjet printer directly onto the subject's head, allowing precise placement of these "electrodes" within minutes.
Once dry, the ink acts as a brain wave sensor. Tested on five volunteers, the technology performed as effectively as traditional systems, while offering much greater comfort. The ink, thinner than a human hair, even ensures signal stability for 24 hours, compared to just six hours for conventional electrodes.
The researchers also printed conductive wires directly onto the skin, effectively eliminating external cables. Eventually, these tattoos could integrate wireless transmitters, making EEG completely autonomous and mobile.
These innovations are not limited to medical diagnostics. They pave the way for brain-machine interfaces, enabling, for example, the control of devices through thought. Patients with paralysis or epilepsy could benefit from real-time monitoring thanks to these miniaturized devices.
Next steps include adapting the ink for long hair and increasing its resistance to wear, especially during sleep. The potential is immense: from overnight monitoring of sleep disorders to daily applications for patients with chronic conditions.
More than a medical breakthrough, this technology marks a step toward smoother integration between humans and machines. With such precision and ease of use, electronic tattoos could well become the key tool in the neuroscience of tomorrow.
What is an electronic tattoo for the brain?
An electronic tattoo for the brain is a thin layer of conductive material printed directly onto the scalp. It functions as an electrode to measure brain activity.
Made from biocompatible conductive polymers, it can penetrate hair to reach the scalp. Once in place, it captures the electrical signals emitted by the brain, just like a traditional electroencephalogram (EEG), but with fewer constraints.
Unlike classic electrodes, this device is temporary and painless. It is quickly applied using an inkjet printer guided by an algorithm. These tattoos offer millimeter-level precision while eliminating cumbersome wires.
The goal is to make these tattoos more robust and capable of withstanding movement or moisture, to improve their use in contexts such as sleep or brain-machine interfaces.
Article author: Cédric DEPOND