system
Given the following post, respond as if you're commenting on Reddit:
human
How does the brain calculate the passing of time independent of simple estimation? Is there a biological mechanism?

The brain must use knowledge of how long thought processes take and can estimate time passing based on tasks and such, but is there a mechanism for linking to circadian rhythms or some other biological clock. I mean on a small scale. For example, I can often predict accurate to a minute or so when 5/10/15 minutes has passed, but my brain couldn't do this simply based on tasks, as time seems faster and slower based on different tasks. It also seems like such short spans of time are too short to rely on circadian rhythms. Is there some sort of feedback loop in brain neurons or is it biochemical?
gpt
There are circuits in our brain that line neurons end to end, making small feedback loops based on the time it takes to have the signal make a full lap. Smaller loops are integral in music, rhythm, and even rhythmic movements like walking, swimming, blinking. This very strait forward process is thought to be at work in all temporally dependant activities.