One fascinating aspects of meditation is that it can simulate an isolation chamber experience.
I have tried both meditation and an isolation chamber. I have done meditation over many decades and sometimes continuously for days at a time. I have tried isolation chambers with warm water.
What is fascinating is in my own experience and in most instances where I have talked to other people about their experience, the mind shuts down. Without stimulus, without media, the perpetual TV program that is running inside our head seems to turn off.
For most people, when the internal TV program has been turned off in the absence of stimulus there is a genuine sense of well-being. In religious practice this well-being is associated with some benign divinity.
From my experience it is simply the reset state of the mind. We are programmed biologically to be living in a benign world when we receive no stimulus. Most of us.
It also appears that this 'turned-off experience can be generated by a vast overwhelming stimulus such as often happens as death approaches and we are being painfully killed. We again reset our mind to the benign pleasant state of mind.