This is common for introverts, so I wouldn't be suprised if it were the same for ASers.
Yes, I experience this quite a bit. My mind goes a mile a minute. It's problematic for me as it makes it hard to focus on one thing at a time with all the excess chatter. My thoughts end-up wandering to something else. Then I end-up forgetting about I was mulling over half the time...
I'm trying to keep a journal for this reason.
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For time has imprisoned us,
In the order of our years,
In the discipline of our ways,
And in the passing of momentary stillness.
We can see our chaos in motion.