https://astralcodexten.substack.com/p/jhanas-and-the-dark-room-problem

The Dark Room Problem in neuroscience goes something like this: suppose the brain is minimizing prediction error, or free energy, or whatever. You can minimize lots of things by sitting quietly in a dark room. Everything will be very, very predictable. So how come people do other things?

The usual workaround is inbuilt biological drives, considered as "set points". You "predict" that you will be well-fed, so getting hungry registers as prediction error and brings you out of your dark room to eat. Et cetera.

Andrés Gómez Emilsson recently shared a perspective I hadn't considered before, which is: actually, sitting quietly in a dark room is really great.

The Buddha discussed states of extreme bliss attainable through meditation:

Secluded from sensual pleasures, secluded from unwholesome states, a bhikkhu enters and dwells in the first jhāna, which is accompanied by thought and examination, with rapture and happiness born of seclusion (Samyutta Nikaya)

I had always figured that "sensual pleasures" here meant things like sex. But I think maybe he just means stimuli, full stop. The meditator cuts themselves from all sensory stimuli, eg by meditating really hard on a single object like the breath and ignoring everything else, and as a result gets "rapture and happiness born of seclusion".