Original news release was issued in Slovak by the Slovak University of Technology.
At Slovak University of Technology, professor Viera Stropjaková is working hard with her team to design an ultra-compact device for stress monitoring. This system would primarily find its use in medical science, but it could be helpful in many more areas. Nowadays, we accept stress as a normal aspect of our daily life, which is why we often do not realize all its causes and effects. Stress can complicate illnesses and injuries, making them a lot worse and much harder to cure.
So far, there are tests done only to monitor one’s immunity to stress. An effective and accurate stress monitoring system would be a useful tool for most doctors. Part of the problem in designing such a device are the reactions of human body to stress. As Stropjaková notes, these are: rising blood pressure, dilated pupils, widened bronchi, widened blood vessels in skeletal muscles, and heavier breathing. Some of them are quite hard to monitor and, for example, blood pressure data by itself will not produce accurate information about stress levels. However, there is an interesting product of these processes. Psycho-galvanic reflex is characterized by change of conductivity of person’s skin.
“It is precisely this relative change of the conductivity of skin, that our sensor measures. In the beginnings, we worked with a version of monitoring device in the form of wristwatch, but it turned out that the index finger of the non-dominant hand is the best place for sensing,” explains professor Viera Stopjaková, head of the research team.
Until recently, it was assumed that this happened because of excessive sweating in stressful situations, but then it was observed that the top-most part of our skin (stratum lucidum) includes a barrier that changes in thickness due to nerve activity. This information is collected by the sensor, and with addition of easily monitored data (blood pressure, heartbeat, and breathing frequency) produces accurate information about stress levels. The team also developed an app to monitor and process the recorded data. It saves the recorded information, lets the user browse history and informs a physician of critical stress levels.
Last but not least, the whole system was designed to use minimal amount of energy, the monitoring can thus go on for two or three days on a single charge. The prototype can be seen on the above image and it was tested by the students. “It was interesting to see that we sometimes really do not perceive how many instances put us in stress. The testing showed considerable amount of stress even during common actions, for example, when we are concentrated on work and an unexpected phone call disturbs us,” says Stopjaková. The team at STU is looking at this research from a long term perspective, and currently also works on an energy-autonomous biochips, which could harvest energy from human body and possibly avoid complicated battery replacements.