Not that I'm going to claim the "default state of human cognition" is either sequential or "functional"... but I'll add anecdote to Peaker's anecdote and state

Not that I'm going to claim the "default state of human cognition" is either sequential or "functional"... but I'll add anecdote to Peaker's anecdote and state that the way you're describing your mental processes feels very alien to me as well.