Hey James, welcome to DhO.
One of the first insights a meditator has is that they are not their thoughts, that thoughts just seem to be arising and passing away selflessly. As a monk whose name eludes me said, "The mind produces thoughts like the mouth produces saliva." This insight is described in the "
Mind & Body" stage in the Progress of Insight.
As a meditator's concentration abilities develop and they progress/cycle through the various stages of insight, the nature of what thoughts and thinking are starts to become more complex.
In my practice early on, I noticed that what I had previously held to be straightfoward as "me thinking a thought" was in fact a multi-layered, granular and elusive process. When sitting, and eventually throughout the day off the cushion, I noticed that the mind seemed to be assembling itself moment-to-moment very rapidly out of as Shagrol says, "
subtle sensations, sensations, urges, subtle emotions, emotions, proto-thoughts, one-word thoughts, and full sentence thoughts".
Eventually, the awareness of this process became such that I noticed that this mindstream had a somatic and energetic quality that was actually "beneath" any linguistic meaning. The mindstream would become so subtle and granular in the spatial area "inside the head" and eventually turn into little energetic streams, eddies and whirlpools. These experiences were most common during the "Arising & Passing Away" and "Equanimity" stages in the progress of insight.
For me, it took a few months of practicing with Noting and "Choiceless Awareness" before taking the mindstream as an object of meditation became effortless. After that point, it was really a matter of subtly inclining awareness towards it. Insight into the mindstream will develop and deepen as one continues with consistent practice.
