They're conjugate in the sense that thoughts will be part of many different trails, while trails are composed of many different thoughts. Focus too much on the specific thought, and one loses track of which specific trail; focus too much on the trail, and one loses track of which thought. (so a self-reinforcing coherent group of thoughts and trails would be a gaussian?)

Interesting perspective. I imagine trails as graphs and stepping through a graph is like looking at the components of a time-domain representation of a signal so in my mind associative trails are a time-domain representation of thinking. But you might be onto something. I've been thinking about how to incorporate search into something I'm working on and search can be considered a frequency representation because finding and ranking documents is about finding the frequency components relevant to the query. If associative trails can incorporate search then that might be a good enough frequency-domain representation.

In the context of knowledge engineering I think "frequency" representation has to be dynamic and search is a very simple form of dynamism. But I might be thinking about this the wrong way and your view might be more correct, i.e. static content = frequency domain, dynamic content = time domain.