I love Panksepp's work, and look forward to these three measures being readily available in the usa.
Note: the video first gives a summary of the 7 emotional systems that have been mapped in the brain, then goes into which 3 are related to depression, then 3 ways of countering depression by activating those 3 emotional systems. Not his best video, but still a useful introduction for those who might be interested in learning more.