What Tech could we find inside the Vitality Sensor?

Well the Vitality Sensor came out of nowhere at last years E3, no one expected an announcement like it nor expected Nintendo to delve any further into health related gaming/monitoring. A lot of speculation about the Vitality Sensor started with plain jane horror games designed to scare you when your relaxed etc by just monitoring your heart rate/pulse. But what more could this device be? Well, the only way in which we can gain some sort if idea is to actually look at what the health industry does with finger monitors. This is all speculation as to what the Vitality Sensor can do as, as far as we know no one has ever had a hands on with the device therefore we cannot attain what the device can do or does when attached to a finger.