8 years ago I was introduced to the Institute of HeartMath, a nonprofit organization researching heart intelligence and producing scientifically tested tools to improve emotional state and performance.  Champion golfer Ian Woolsnam has been using HeartMath technology to improve his game and also for his health problems (M.E. and Ankylosing Spondylitis). I often use their Freeze Framer / emWave software in my practice. The software analyses your heart rate coherence via a finger sensor.  So why is this useful? 

For clients who have had a trauma and have become dissociated as a way of coping the HeartMath software has often been useful for me to see in real time, as I'm talking to them, how they feel when certain subjects or triggers are mentioned, as often they won't be aware of it themselves.  Through this they can gain awareness of how and when they are 'switching off.'  I can then introduce strategies and techniques for their everyday lives for them to become aware of their internal state and thereby begin 're-connecting'.

I also work in a school with children with dyslexia and behaviour problems. Again the Freeze Framer has proved very useful. This technology was originally developped for anger management so I'm sure you can imagine how it can be used with some school children!  In a particular case, I helped a 13 year old boy who apparently had AHDD.  We used the game version of the software so that he could use his own mind to control it and it was quite astonishing how quiet and calm he became when he focused.

I've even used it for myself to meditate to.  The main thing about this is that we know the heart sends more messages to the brain than the other way round and once you can feel heartfelt positive emotions such as gratitude, love, joy, kindness then your heart enters a coherence state that directly influences your mind and body. So by practicing you gain control of yourself whatever is happening, but especially in situations which you would have found stressful or challenging in the past.