A device that measures someone’s unique response to a weak electric signal could let medical devices such as blood-pressure cuffs automatically identify the wearer and send measurements straight to his or her electronic medical record, Technology Review reports. For now, nurses, patients, and doctors juggle the job of keeping patients’ identities straight. But computer scientist Cory Cornelius at Dartmouth College, in New Hampshire, has developed a wristwatch-like device that measures a person’s “bioimpedance” to identify him or her to medical monitoring devices. Authenticating users of medical devices could have various practical benefits. A household might share an exercise-monitoring device, for example, and authentication would match household members with their own results.