Sensory Deprivation And Zen

Poul Anderson, Harvest Of Stars, 20.

"How long could [download Guthrie] endure near-total sensory deprivation before his mind began to spin apart?" (p. 191)

Should zazen keep us sane during sensory deprivation? I might ask this in the group although questions are supposed to express spiritual concern, not intellectual curiosity. Maybe no one knows. Are some yogis bricked up with food passed through a hole for extended periods? And, if so, what does it do to them?

In zazen, we face a wall in a quiet room for a timed period. We see the wall, feel whatever we are sitting on and hear any background sounds although these should be few. We would hear and respond to a fire alarm. We are not in a trance. We let thoughts arise and pass without deliberately extending them. So maybe this practice would make it easier to endure sensory deprivation? But there are physiological effects over which we would have no control. If hallucinations started, then maybe we would be able to let them arise and pass? But what else would happen?

Zazen is beneficial but how much can it cope with?