The more likely possibility is that the background TV acts as "noise canceller", allowing your focus to hover between non-specific environmental sound, and your internal thoughts. Neither wins your attention, so your mind is at rest and you sleep.

The echo of our internal thoughts darting around as we approach sleep is quite normal. In the absence of TV background noise, the trick would be to not focus or chase or indulge the thoughts but "allow" them to simmer without your involvement, or allow them to pass by without looking at each one in depth; be indifferent from a distance. That's a technique not difficult to master, but is basically how to still your mind and go to sleep.