Never the less, self trackers can make more data available. In particular, many devices measure stress and [[Mood]] through [[Tools for heart rate or pulse|heart rate]] and [[Galvanic skin response]], kind of like a polygraph<ref>https://en.wikipedia.org/wiki/Polygraph</ref>. | Never the less, self trackers can make more data available. In particular, many devices measure stress and [[Mood]] through [[Tools for heart rate or pulse|heart rate]] and [[Galvanic skin response]], kind of like a polygraph<ref>https://en.wikipedia.org/wiki/Polygraph</ref>. |