Is there a name for this mental state I sometimes find myself in after reading for a while? My breathing slows, I start to feel very "focused", and my physical perceptions start to blur. The book or screen I'm reading seems simultaneously both small/near and huge/far, my limbs feel simultaneously heavy and weightless, and time seems to be simultaneously slowing down and rushing forward. Has anyone here experienced this, and do you know what it's called?
You're describing the state of Flow.https://www.researchgate.net/figure/Flow-state-frustration-anxiety-zone-and-boredom-zone-Reproduced-from-8_fig1_325283635
Could it be a form of hyperfocus?
Maybe, trance ?
It sounds like a meditation-like state. Focussing very deeply on something - in your case, the book I guess - can make all other sensations fade into the background. There are many kinds of concentration meditation that are like that. On the other hand, you do seem to be aware of these going on and that is more like mindfulness meditation. The Mind Illuminated teaches that both are needed in advanced practice. Maybe you lucked into a comparable mind state. Can you reproduce it intentionally?
I've never tried to make it happen intentionally. It does seem to happen more often when most of the lights are off and I'm the only one still awake, so maybe it is a focus/attention thing. Something about the combination of low mental effort, low sensory input, and the pleasure reward from reading?