In the 1950s and 1960s, China was rumoured to be using solitary confinement to “brainwash” American prisoners captured during the Korean War, and the US and Canadian governments were all too keen to try it out. Their defence departments funded a series of research programmes that might be considered ethically dubious today.
The most extensive took place at McGill University Medical Center in Montreal, led by the psychologist Donald Hebb. The McGill researchers invited paid volunteers – mainly college students – to spend days or weeks by themselves in sound-proof cubicles, deprived of meaningful human contact. Their aim was to reduce perceptual stimulation to a minimum, to see how their subjects would behave when almost nothing was happening. They minimised what they could feel, see, hear and touch, fitting them with translucent visors, cotton gloves and cardboard cuffs extending beyond the fingertips. As Scientific American magazine reported at the time, they had them lie on U-shaped foam pillows to restrict noise, and set up a continuous hum of air-conditioning units to mask small sounds.
After only a few hours, the students became acutely restless. They started to crave stimulation, talking, singing or reciting poetry to themselves to break the monotony. Later, many of them became anxious or highly emotional. Their mental performance suffered too, struggling with arithmetic and word association tests.
But the most alarming effects were the hallucinations. They would start with points of light, lines or shapes, eventually evolving into bizarre scenes, such as squirrels marching with sacks over their shoulders or processions of eyeglasses filing down a street. They had no control over what they saw: one man saw only dogs; another, babies.
Some of them experienced sound hallucinations as well: a music box or a choir, for instance. Others imagined sensations of touch: one man had the sense he had been hit in the arm by pellets fired from guns. Another, reaching out to touch a doorknob, felt an electric shock.
When they emerged from the experiment they found it hard to shake this altered sense of reality, convinced that the whole room was in motion, or that objects were constantly changing shape and size.
The researchers had hoped to observe their subjects over several weeks, but the trial was cut short because they became too distressed to carry on. Few lasted beyond two days, and none as long as a week. Afterwards, Hebb wrote in the journal American Psychologist that the results were “very unsettling to us… It is one thing to hear that the Chinese are brainwashing their prisoners on the other side of the world; it is another to find, in your own laboratory, that merely taking away the usual sights, sounds, and bodily contacts from a healthy university student for a few days can shake him, right down to the base.”
In 2008, clinical psychologist Ian Robbins recreated Hebb’s experiment in collaboration with the BBC, isolating six volunteers for 48 hours in sound-proofed rooms in a former nuclear bunker. The results were similar. The volunteers suffered anxiety, extreme emotions, paranoia and significant deterioration in their mental functioning. They also hallucinated: a heap of 5,000 empty oyster shells; a snake; zebras; tiny cars; the room taking off; mosquitoes; fighter planes buzzing around.
A clip from BBC Horizon’s Total Isolation experiment – read more information about the programme here.
Why does the perceptually deprived brain play such tricks? Cognitive psychologists believe that the part of the brain that deals with ongoing tasks, such as sensory perception, is accustomed to dealing with a large quantity of information, such as visual, auditory and other environmental cues. But when there is a dearth of information, says Robbins, “the various nerve systems feeding in to the brain’s central processor are still firing off, but in a way that doesn’t make sense. So after a while the brain starts to make sense of them, to make them into a pattern.” It creates whole images out of partial ones. In other words, it tries to construct a reality from the scant signals available to it, yet it ends up building a fantasy world.
Such mental failures should perhaps not surprise us. For one thing, we know that other primates do not fare well in isolation. One of the most graphic examples is psychologist Harry Harlow’s experiments on rhesus macaque monkeys at the University of Wisconsin-Madison during the 1960s, in which he deprived them of social contact after birth for months or years. They became, he observed, “enormously disturbed” even after 30 days, and after a year were “obliterated” socially, incapable of interaction of any kind. (A comparable social fracturing has been observed in humans: consider the children rescued from Romanian orphanages in the early 1990s, who after being almost entirely deprived of close social contact since birth grew up with serious behavioural and attachment issues.)
Secondly, we derive meaning from our emotional states largely through contact with others. Biologists believe that human emotions evolved because they aided co-operation among our early ancestors who benefited from living in groups. Their primary function is social. With no one to mediate our feelings of fear, anger, anxiety and sadness and help us determine their appropriateness, before long they deliver us a distorted sense of self, a perceptual fracturing or a profound irrationality. It seems that left too much to ourselves, the very system that regulates our social living can overwhelm us.
Take the 25,000 inmates held in “super-maximum security” prisons in the US today. Without social interaction, supermax prisoners have no way to test the appropriateness of their emotions or their fantastical thinking, says Terry Kupers, a forensic psychiatrist at the Wright Institute in Berkeley, California, who has interviewed thousands of supermax prisoners. This is one of the reasons many suffer anxiety, paranoia and obsessive thoughts. Craig Haney, a psychologist at the University of California, Santa Cruz, and a leading authority on the mental health of inmates in the US, believes that some of them purposefully initiate brutal confrontations with prison staff just to reaffirm their own existence – to remember who they are.