IT'S ALL IN YOUR HEAD:

One of the greatest challenges for most doctors is the struggle to believe in the truly subconscious nature of their patients' psychosomatic symptoms. Pierre Janet, a French philosopher and psychologist in the late 19th century, was pivotal in the development of what we call the subconscious. He described consciousness as those sensory experiences and thoughts of which we are actively aware, whereas our subconscious is a place to store information not immediately available to the conscious mind.

Janet thought our consciousness could expand and contract, and choose what we perceived and what we ignored. There are examples of this in everyday life - looking for a friend in a crowd, for example. They are right in front of you, waving, but somehow you look right past them. "You must have seen me," they say afterwards. "You looked right at me!" But you didn't. For a moment, your mind employed selective attention and blocked something from your view.

Janet said that a separation between the subconscious and conscious could see memories and feelings exist in parallel parts of the mind, neither knowing of the other. This he referred to as dissociation, arguing that a psychological trauma could cause the subconscious to slink away so it was no longer available. In his model, it would be possible for Yvonne both to see and be unaware of seeing at the same time.

I saw Yvonne just once more, to arrange her psychiatry assessment. What little I would learn later would come in correspondence from the psychiatrist. These letters were factual, plainly written but always slightly cagey, as they have to be. Yvonne's accident at work had resulted in an argument at home, the first letter said. Gerald had been called away from work to collect her from hospital. When he learned what had happened, he insisted she resign instantly. Yvonne, whose vision was not affected in the incident's immediate aftermath, tried to plead otherwise, but he called her employer and offered her resignation. Later that evening the argument became moot when Yvonne discovered she had lost her vision.

The letter stated that Yvonne was struggling at home. Gerald had hired a housekeeper who did all the housework and helped with the children, but would not take responsibility for Yvonne. This left her feeling both superfluous and frightened.

After meeting the psychiatrist, Yvonne agreed to an admission to the psychiatric ward for intensive rehabilitation and talking therapy.

The final letter came months later:

I am happy to let you know that Yvonne's vision has returned to normal. She has engaged well with treatment, although both she and her husband still struggle a little to accept the diagnosis in full. She has recently moved back to the family home and reports that things are going well. So much so that she has decided it would not be right to return to work.

Yvonne has crossed my mind several times since then, and I feel I did her a disservice. I was a fool to question her motives and insight because she had, suspectingly or unsuspectingly, told me exactly how things were when she handed me the card she had made. A woman who wishes to lie and fake wears dark glasses , carries a cane and stumbles about. That woman certainly does not draw a picture. Yvonne's drawing was evidence not of guilt but of innocence, and, at the moment she handed it to me, it was I who could not see.

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