Why is isolation so dreadful for humans? As the clinical psychologist points out, it interferes with one of our brain’s basic needs.

Question: What happens when one is deprived of sensation?

Marvin Zuckerman: Well, what was happening psychologically, they’d just become bored and restless if they were high sensation seekers. If they were low sensation seekers, they were fairly comfortable and once they had high anxiety trait – we measured how much they would move around. We could actually measure their restlessness. At the beginning, the first three hours, there was not difference, but as time went on the highs being more and more restless, twitching, turning on the bed. They began to sing to themselves even though they knew they weren’t supposed to speak or to simulate themselves. They began to stimulate themselves. So, that was the expression of it.

If you go a long period – what’s happening in the brain is, over longer periods of time, even over shorter periods is that the brain waves are slowing down. The basic arousal in the brain, the alpha waves are getting slower. Okay. And that, for most people, is unpleasant. To go below your optimal level of arousal for any prolonged period of time becomes unpleasant. And if you give them any kind of stimulation in sensory deprivation, even looking at meaningless blotches of color they will avidly press a bar to do that. They are being deprived of something, variety and variety of stimulation and when you deprive people of that, that is very aversive to them. It’s one of the ways of torture actually of putting people – it’s not just the social and sensory deprivation when you put someone you know. It’s the sensory deprivation. You put people in an environment they might not be under sensory deprivation, but if nothing is varying in their sensory environment, it is becoming increasing aversive.

Question: Is this form of torture more human than others?

Marvin Zuckerman: No, it’s not humane, and it’s not – solitary confinement it’s called in prison. It’s a punishment when they put them in solitary confinement, which usually sensory deprivation as well because even if there is light in the cell, there’s no variation. Nothing is changing, mo one to talk to. Part of social isolation is the lack of social stimulation. So, over time, it is very torturous. It’s a mental torture of a sort that could be very effective. The torturer is often – they usually isolate their prisoners before they begin interrogating them because then they respond – they have at tendency to respond to any stimulation, even interrogation is more primed by the sensory deprivation