What I mean is, negative feedback loops are used whenever a device (or a person?) is in control... Positive feedback is inflationary economics or the howling feedback in a public address system...

But using positive/negative the less technical way, I'd like to positively recommend watching the clip of Andrew Austin at Professional Hypnotherapy and NLP - Chichester, West Sussex

I caught the analogy to weight loss early on -- that's my physics training -- but keep watching and listening, because there's more. How about the rep systems involved in 'digesting information'? (That's a little throwaway about 14 minutes in.)

And there is some very, very important information at the end for anyone who works with victims of Post-Traumatic Stress Disorder.

A big round of applause, sir!