David Kotz, Rianna StarheimBracelets and amulets are in the works at Dartmouth’s Institute for Security, Technology, and Society. Rather than items of mere adornment, the scientists and engineers are constructing personal mobile health (mHealth) devices—highly functional jewelry, as it were.

mHealth is a rapidly growing field where technology helps you or your physician monitor your health through mobile devices. This approach can offer more accurate and timely diagnoses as well as lower health costs. However, smartphones are often used to transmit collected medical information, and these transmissions are vulnerable to hacking.

Professor David Kotz tests the prototype bioimpedance biometric bracelet, observed by Rianna Starheim ’14, research assistant in the Department of Computer Science, and Ryan Halter, assistant professor of engineering at Thayer. (photo by Eli Burak ’00)

David Kotz ’86 guides a research group whose focus is mHealth. Kotz, professor of computer science and associate dean of faculty for the sciences, works with a diverse team whose members include graduate students (Shrirang Mare and Cory Cornelius), a postdoctoral associate in computer science (Jacob Sorber, now an assistant professor of computer science at Clemson University), a computer programmer (Ronald Peterson), faculty and technical staff from Thayer School of Engineering and the Geisel School of Medicine (Ryan Halter and Joe Skinner), and others. Their wide-ranging skills are being brought to bear in a field that is redefining the relationship between patient and doctor.

Collection and communication of medical information via mHealth systems can help a physician monitor patients with chronic diseases or other medical concerns on a more frequent basis. The ability to look at the data remotely and assess a patient’s condition might also mean fewer trips to the hospital or the doctor’s office.

One of the Institute’s intriguing wearable devices under development has actually been christened “Amulet,” first announced at a conference in February 2012. Its foremost feature would be a wireless communication capability, possibly using something like Bluetooth. As envisioned, Amulet would function as a communications hub for mHealth devices on a person’s body, akin to a local area network, ultimately connecting them to an electronic medical records system.

“We see our Amulet concept as a means to collect body-area sensor data,” Kotz explains. “The device could collect electrocardiogram signals from a heart monitor, obtain glucose readings from a glucose meter, and even talk to your insulin pump to control the insulin injections.”

Looking like a fancy digital watch, incorporating a display and computing capabilities, Amulet’s ultimate utility would hinge on its ability to accurately and securely communicate and correlate the collected sensor data.

In a related development, led by Dartmouth graduate student Cory Cornelius ’07, this group presented a paper in August 2012 that described a prototype biometric bracelet that adds security to the system.

Another jewelry-like mHealth device, the “bracelet” could be functionally integrated with the Amulet. The bracelet applies a tiny alternating current to a person’s skin at different frequencies, to which each person’s body seems to respond uniquely. These unique responses, based on variations in body tissue shape and thickness, could represent a person’s biometric “fingerprint,” expressed in terms of bioimpedance—a measure of how the body’s tissues resist the electric current.

“We imagine a device [the bracelet] that can be worn on the wrist and unobtrusively recognize its wearer,” writes Cornelius and his co-authors. “Without any other action on the part of the user, the [mHealth] devices discover each other’s presence [and] recognize that they are on the same body.” This network learns from the unique electrical signature of the wrist device whose body they are on. The network’s own configuration could then be used as a basis for encryption in establishing reliable and secure external communications.

“The Amulet and the bracelet are complementary ideas, still under development,” says Kotz. “We’re still building an Amulet prototype and we have more to do to validate bioimpedance as a biometric method. We think these concepts, once fully proven, offer great potential for mHealth.”

Dartmouth College

September 12, 2012