Daniel M. Ingram:
Muscle spasms: nearly always third insight stage, that of the Three Characteristics, interest in Kriyas and the like with the muscle spasms letting up and meditation improving, very likely early A&P stuff.
Thank you very much, Daniel. The strange thing is that, although I can identify with some of the things depicted in ñanas 1 & 2, it does not seem very impressive, more subtle sometimes only faint or intellectual glimpses. I imagine those stages to be more impressive and more thoroughly processed in terms of awareness. Am I mistaken here?
For example, I certainly see some cause and effect and the feeling that thoughts and emotions simply arise and are not really controlled by me but I am not sure of the mental pulse thing you wrote about in ñana 2. Might one pass those stages without really noticing them or them leaving a strong impression? Do these stage overlap and sometimes mix up with each other? Sorry, I can't remember having read anything about that in your book or the wiki.
Indications for ñanas 3 or even 4 might be that I've recently added some spinal breathing (pranajama) to my practice intuitively (after reading about it) and am now in a phase where I can sometimes feel mental obstructions and resistance almost like I feel muscle tensions and hence loosen them voluntarily. I try to interfere less with the meditation process and put more energy into the 'observer' than into the 'doer', as Ajahn Brahm would put it. There's also a rekindling interest in (lucid) dreaming.
Whatever, both, your and Richards answers are of great help and investigating the 3Cs more thouroughly is probably the way to go for me now.
Thanks for your help!
Andreas