system
Given the following post, respond as if you're commenting on Reddit:
human
Can a brain completely deprived of sensory input perceive time?

I wonder, with no outside reference, if the human brain has way to tell that time has passed. I have heard that people in sensory deprivation tanks lose track of time, but what if, somehow, no sensory input made it to the brain at all, would it be able to perceive the passing of time?

Thanks, Science is Awesome <3

Edit: (Question I asked in comments) What if I lost all sensory input for an incredibly short period of time, sub-millisecond, would I notice or would that millisecond just cease to exist for me? Memories are built upon sensory input so wouldn't that time be lost like moments spent in sleep?
gpt
You can, you'd just be really bad at it. See: Campbell, S. S. (1990). Circadian rhythms and human temporal experience. In R. A. Block (Ed.), Cognitive models of psychological time, (pp. 101-118). Hillsdale, NJ: Erlbaum.

I think where you're going wrong is that memory is *not* dependent on external sensory input. Repeat a word over and over in your head and pretty soon, you have a new memory with no sensory input.