The scientist in charge, Professor Donald Hebb, was surprised by the results.
Sensory deprivation really is a way of producing extreme monotony.
It's apparently a horrible experience, getting worse and worse.
Some of our subjects talked about cruelty.
What they said was that the degree of boredom became intolerable and was,
one subject said, as bad as anything that Hitler had ever done to any of his sub to his victims.
The scientists had discovered that the human brain needed constant stimulation for its healthy functioning.
However, the experiments were considered too cruel and were closed down.
But since then, there have been 40 years of scientific advance.
Knowledge of the brain has moved on enormously.
During Hebb's period, we know very little about what was going on inside the brain.
The only way you could visualise the brain itself involved very invasive processes.
Now we have things like CAT scans, MRI scans, PET scans.
They allow us to know a lot more about what's going on inside the brain
and about the functional relationship between different parts of the brain.