Good vibrations: Your cell phone could soon learn if you're happy or sad

CAMBRIDGE, Mass. — What if your computer or smartphone could tell if you're happy or sad?

A new device developed by researchers at the Massachusetts Institute of Technology aims to detect emotions by sending wireless signals that measure heartbeats as the signals bounce off a person's body.

Researchers from MIT's Computer Science and Artificial Intelligence Laboratory say their device is 87 percent accurate in using heartrate and what it's already learned about a person to recognize joy, pleasure, sadness or anger, after the device first measures how each individual's body reacts in various emotional states.

It works like an electrocardiogram monitor but without needing a sensor on the body to measure heartbeats.

They say it could one day be used by advertising agencies to gauge audience reaction or in health care to diagnose depression or anxiety.