I was looking up fractals the other day on wikipedia and it says that "A mathematical fractal is based on an equation that undergoes iteration, a form of feedback based on recursion." And I thought it was interesting, because on LSD I not only saw interconnected fractal-like mandalas, but I also got that mirror-facing-mirror infinite feedback spiral feeling at times too, especially when I'd analyze my own consciousness. Both are kinda based on this idea of recursion. I was wondering if anyone here's read Douglas Hofstader's book 'I am a strange loop', because his ideas seemed to compliment my personal experiences with this mysterious drug. Or if anyone's had any similar thoughts about the brain...
Hostadter is fantastic, he opened my eyes to a whole world I didn't know exist. I have the book you mention in my room but haven't read it yet. I have however read the first of that series if you will, "Godel, Escher, and Bach: An Eternal Golden Braid". It's about the true nature of intelligence and he approaches it by incorporating recursivity found in the music of Bach, the art of Escher, and the math of Godel. It's a phenomenal book that everyone should read once in their life; one critic said 'it's an entire humanistic education in one book', i agree completely. He also has a fantastic book "The Mind's I", which is on the nature of Self and is equally monumental, though it may raise more questions than answers for you
I haven't read it, but I am interested in fractals. Douglas Rushkoff's online book Cyberia has an interesting little discussion about fractals. I think once you start thinking about the equations and the recurrance of things as in fractals, you start to notice it within little things in your life. Something will happen, and you'll think, hey, wasn't there a small event related to this 3 months ago? Or even within your own thoughts, like deja vu. Chaos maths, too, is so very interesting.
I've never seen "trails" on acid so to speak... maybe I just haven't taken a high enough dose yet. But I think the picture on the cover of 'Strange Loop' is pretty psychedelic... http://manwithoutqualities.files.wordpress.com/2008/04/strangeloop-cover.jpg
I think trails just depend on the person, I did just a tab of acid and got trails, maybe not as intense as a huge-trip's trails, but trails nonetheless