Tattoo with benefits for the brain Person

Tattoo with benefits for the brain

Going to electrocardiography in the morning, it is better not to wear tights and sweatshirts with a narrow sleeve, otherwise you will have to take off all your clothes in the doctor's office. The queue in the corridor after a prolonged procedure will not meet with satisfied faces. Roll up your trousers and sleeves, lie down on the couch," the nurse says dryly and adds a little more gently, "Try to relax. Relaxation is difficult, because before connecting the electrodes, a woman in a white coat applies a nasty cold gel to the patient's wrists and ankles, which still needs to be wiped off the skin after diagnosis.

Inconveniences during the procedure, often erroneous results, the impossibility of long—term measurements, as well as the need to monitor the activity of muscles and brain - all this pushes scientists to discover new methods and devices for diagnostics. In 2015, Francesco Greco, head of the Laboratory of Applied Materials for Printed and Soft Electronics at the Institute of Solid State Physics at the Graz University of Technology, together with Italian colleagues developed the so-called tattoo electrodes.

These are conductive polymers that are printed using an inkjet printer on standard tattoo paper. The tattoo is glued to the skin and does not require liquid lubricant to measure electrical signals. The thickness of the electrode from 700 to 800 nanometers — about 100 times thinner than a human hair — allows it to adapt to all skin irregularities. In 2018, the team optimized the created electrode. The modification opened up new ways in electrophysiological studies of the heart and muscles: electrocardiography (ECG) and electromyography (EMG).

The breakthrough briefly quenched the research thirst of scientists. Now the Greco group has transformed dry thin electrodes in such a way that they can also be used in electroencephalography (EEG) — to measure brain activity. The development is described in detail in an article recently published in npj Flexible Electronics.

Brain waves are in the low frequency range, and EEG signals have a very low amplitude. They are much more difficult to receive with high quality than EMG or ECG signals. To achieve the same efficiency as conventional electrodes, the developers optimized the composition of the conductive polymer and the thickness of the paper. The modification led to a tighter connection with the skin. Clinical trials have shown that EEG measurement with optimized tattoos is as successful as with conventional EEG electrodes.

In addition to dryness and the possibility of long-term measurements, among the advantages of tattoo electrodes, the developers indicate the cost. Thanks to inkjet printing and commercially available substrates, "tattoos" are much cheaper than conventional EEG electrodes.