Philip Hensher: The so-called 'insane' whose lives are thrown away

In 1972, the psychologist David Rosenhan conducted an experiment into the validity of diagnoses of mental health. Eight associates of his, all in perfect mental health, went to psychiatric hospitals and told them that they were hearing voices. Their behaviour in all other respects remained normal. All eight were admitted to hospital, mostly with diagnoses of schizophrenia.

Where records were kept, almost all the other patients realised immediately that the researchers had no mental health problems. It took the hospitals, however, up to 52 days to realise the same thing, and in one case, the researcher was only discharged with considerable difficulty. Subsequent to the publication of Rosenhan's paper, numerous people with real problems were turned away from American hospitals in the belief that they were psychology researchers.

The debate over Rosenham's experiment goes on, but we've just been reminded in a heartbreaking way that the institutional tendencies he exposed can destroy entire lives. When Rosenham conducted his experiment, Jean Gambell had been in mental institutions for exactly 35 years, for almost no reason. She was to remain in them for another 35 years, and now, at the age of 85, there seems no point in removing her.

Her story begins when she was working at a doctor's surgery as a cleaner, at the age of 15, in 1937. Half a crown – perhaps the equivalent of five pounds now – went missing and she was accused of stealing it. Instead of being prosecuted, she was sectioned under the 1890 Lunacy Act and committed to a mental institution. The money turned up some weeks later. A normal criminal case would have been dropped, but by that point she was institutionalised.

Her family was subject to other pressures; her brothers were themselves placed in care homes. Her family broke up, and when her mother died, a quarter of a century ago, all connection between her and her nearest relations was severed.

Heartbreakingly, she went on insisting to her carers that she did have a family, describing them and giving their names. The institution did not explore this adequately, and indeed seems to have dismissed this as the fantasies of Miss Gambell, who by now had been characterized as feeble-minded. She remained where she was, unvisited.

By chance, one of her brothers went on living in his mother's house, and it was there that a letter recently arrived, addressed to his late mother – it does not seem to have occurred to anyone involved that a woman of 85 might not have a parent still living, though in this case the negligence had a benevolent result. He noticed that the envelope had the name "Jean Gambell" written in the corner, and opened it. It was a questionnaire inquiring whether his mother was satisfied with the care being given to her daughter. He carried out his own inquiries, and discovered that a sister he barely knew about was still living.

When he and his brother visited her for the first time, they were warned that she could only communicate through writing and was unlikely to be able to understand who they were. She came into the room, looked at them, and unhesitatingly said "Alan ... David." and embraced them. A whole life gone.

The medical authorities of the time were, clearly, not just negligent but actively wicked. Whoever engineered the incarceration of Miss Gambell should be reviled, even at this distance in time. But whoever it was, they do not hold the responsibility for keeping her inside for 70 years. The relevant institutions took no effective action to discover why she was there; whether she could be released; what benefit was served by throwing away a person's lifetime. When "care in the community" started to be the watchword of mental health services, it did not seem to apply to one harmless lady already old.

As many observers have established, lives are destroyed not just through the act of incarceration, but through the pressures of mental health care themselves. Erving Goffman's wonderfully-entitled study "Making Out In Mental Institutions" has shown that mental patients "go mad" when under observation, urinating on radiators and so on, when under the microscope. When unaware that they were observed, many in Goffman's study were perfectly rational and well-behaved. The idea, popularised by Ken Kesey's One Flew Over the Cuckoo's Nest, that mental institutions make mental patients is not just an absurd Sixties trendy dogma. Some people genuinely are mad. Some people are just in madhouses.

We have no idea at all whether Jean Gambell had, or has, mental health problems.

If she has, that would not be surprising after the three-quarters of a century of incarceration. Signs of perfect lucidity – her descriptions of her family – were dismissed as if she were ranting about aliens. And that can only be because the professionals saw nothing but a mental patient.

You have to ask the question of how many people there are still in Britain's mental institutions who are regarded by the professionals as harmless, or a pet, who have been there for many years with no particular reason; people who were put there at someone else's convenience who never had the wit or articulacy of David Rosenhan's highly-educated researchers, and could not argue their way out. I don't know. I suspect we never will know.