Although I've never seen this in a book, I've asked a few people to do this, and it seems to work with most people - imagine there is a point in your brain and the rear bottom of your skull. Put your thoughts there, and try to push that point further to the back bottom of your skull. Now try to push that point out of your skull (to the back bottom of it). Once you've pushed it as far as you can - try to think 'words' in your mind. If you've done it right, you should not be able to think in words (that's the instinctive part of your brain. Your logical part that processes language is in an different area)
That was about when I first started dividing the brain into 'zones' (personally i think this is all a quirk of how the brain works, rather than what's actually happening in the brain, but its useful all the same)
I've come to break up body language in 'domains', around the central axis of the body:
- forward = social
- backwards = individual
- right = creative
- middle = auditory
- left = memory
- up = visual
- down = feelings / instincts
After I did this, I notice something very interesting - you can tell who is the dominant partner in any relationship by having a look at photos of them together. The person who's neck is leaning in the most, is the one who is most in love / the more submissive of the two.
I also noticed that way a person is leaning, while it has meaning, is modified by the angle of the neck (relative to the body), and the angle of the face (relative to the body).
And that they use their body language to access different parts of their brain (look into Neurolinguistic Programming to see how this works with someones eyes)
Then I started noticing things about stubbornness, and started understanding the difference between a jutting jaw (which has to have a bent neck) and the forehead pointing forward.
Sometime after noticing these things, I noticed how peoples hands would move in patterns similar to the tone, pitch, and speed of their voice...and realised this is all unconscious.
Having looked extensively into handwriting analysis, I realised that peoples guestures mirrored the nature of their handwriting. The question arose 'why should their hand guestures show glaring similarities to the flow of their handwriting'?
That lead me to realise that people thoughts....move through the different zones (individual / social / visual etc), and personal observation lead me to realise that when I'm nervous, and my voice quavers - so to does my mind. And that if you tried to write at that time, that your writing would likely do the same.
Placing my mind into different zones (using same technique as at the start), and them moving my mind through different zones, I noticed that my voice changed pitch/tone with the zone I moved through - and did so in a consistent way.
That means that the way we talk (rather than what we say) is very subconscious - but it can be trained.
What that means is most body language is subconscious, most is a reflection of what is going on in a persons brain, and you can tell certain things from it.
Of course, people train to present certain body languages too, and I wouldn't put too much stock into conscious body language.
I guess that explanation works for me. Whether or not it does for anyone else, is up to them.
In the end, body language has been the subject of numerous books, but very few experts...who often disagree with each other.