New technologies are transforming healthcare, and smartphones may offer a new solution for detecting mental and physical stress.
A team led by Professor Enrico Caiani of the Department of Electronics, Information and Bioengineering at Politecnico di Milano has shown that it is possible to use smartphones to detect mental health and physical stress – using the accelerometers inside the phones.
Accelerometers in smartphones can be used to acquire a signal associated with mechanical – cardiac activity, generated by heart’s vibrations at every beat, which can be felt by simply placing the telephone on particular parts of the body.
In this study, the team focussed on positioning of the smartphone on the abdomen, at the bellybutton, as part of an application scenario that looks at brief daily acquisition lasting 30 seconds, in a prone position, before getting out of bed in the morning.
By suitably processing this signal, measurements can be acquired of the heartbeat rate and status of activation of the sympathetic-vagal balance, associated with the stress level.
By means of an experimental protocol, which calls for acquisition for each subject in base conditions and during a stressed state induced by mental calculation, it is possible to check the capacity of the indicators measured by the smartphone to capture the increase in stress, on the one hand, and, on the other hand, to determine the best correspondence of the results with the same observations made using an electrocardiogram taken at the same time.
This study, carried out in collaboration with the team led by Professor Gianfranco Parati of the I.R.C.C.S. Istituto Auxologico Italiano, in the Department of Cardiovascular, Metabolic, and Neurological Sciences at Ospedale San Luca in Milan, was recently published in Sensors, the leading open access, peer-reviewed international magazine, on science and technology for sensors and biosensors.
This result opens new horizons and possibilities for using the smartphone as an instrument readily available, for simple self-monitoring of one’s health.