Researchers from California Institute of Technology (Caltech) have developed a wearable device that monitors nine markers of stress in the wearer.

The wearable device, dubbed CARES, which stands for consolidated artificial-intelligence-reinforced electronic skin, is as advertised: an electronic skin.

Source: Caltech

CARES is an adhesive device that is worn on the wrist and assesses both baseline and acute stress levels.

To enable the wearable electronic skin to monitor nine different markers that signal a stress response, CARES reportedly features sweat sensors along with sensors for recording pulse waveforms, skin temperature and galvanic skin response.

Further, the device relies on machine learning to interpret physiological and chemical stress-related data obtained via continuous monitoring.

According to the researchers, hormones such as epinephrine, norepinephrine, and cortisol are released into the bloodstream when a person is stressed. "Sweat becomes rich with metabolites like glucose, lactate, and uric acid, and electrolytes like sodium, potassium, and ammonium. These are substances we have measured before using microfluidic sampling on a wearable sweat sensor."

Setting CARES apart as a monitoring device, the researchers explained, is that sweat sensors are included along with sensors for recording pulse waveforms, skin temperature and galvanic skin response — such physiological signals that indicate stress in predictable ways.

The CARES device is intended to offer early detection of stress severity for quick intervention, particularly in demanding work environments like those encountered by soldiers or astronauts, for instance.

In addition to featuring sensors capable of measuring physiological and chemical biomarkers of stress in sweat — including hormones like epinephrine, norepinephrine and cortisol, alongside metabolites such as glucose, lactate, uric acid and electrolytes like sodium, potassium, and ammonium, for instance — the electronic skin is battery-powered and can wirelessly communicate with devices via Bluetooth.

An article detailing the wearable, “A physicochemical-sensing electronic skin for stress response monitoring,” appears in the journal Nature Electronics.