Other branches of medicine have made amazing advances. Why not psychiatry?
Mrs. A has not been herself for months. Her life is a dull grey. She no longer takes an interest in anything, including her family. Nothing gives her pleasure. She thinks about whether her life is worth continuing. Finally, after much persuasion—because she doesn’t like to think of herself as suffering from a mental disorder—she consults a psychiatrist. What can she expect?
Her psychiatrist is experienced and empathetic. Mrs. A is rather pleased that she is seeing a female; somehow this makes it easier for her to talk about herself. Which is what she does. Her psychiatrist asks very many questions about her current mental state, about her upbringing, about her marriage, about the relationship she has with her children, whether she has many friends, and so on. She makes careful notes.
At the end of the consultation, the psychiatrist tells Mrs. A that she is suffering from depression, that she needs treatment, and that she is likely to recover within about nine months or so, perhaps sooner. Mrs. A, who is a trained scientist, can’t help noticing that her doctor takes no blood samples, does not suggest an X-ray or scan; in fact, the whole diagnostic process is based entirely on the conversation she has just had. Mrs. A goes off with her prescription for some tablets, which her doctor tells her will act mostly on the levels of serotonin in her brain. She also mentions the possibility of psychotherapy.
Down the hall, Mr. B is seeing a cardiologist. He has been having pains in his chest, particularly when he walks upstairs, and playing tennis, which he loves, has become impossible. He has also noticed that he becomes short of breath rather easily. His doctor takes a careful history and tells him that it seems likely that he has a constricted or blocked blood vessel in his heart. But then he refers him for an ECG, a cardiac angiography, to detect exactly where this blockage might be, takes blood to measure certain enzymes, and mentions several other investigations that might be necessary. He also prescribes Mr. B some tablets, telling him that these will relax the blood vessels in his heart and reduce his blood pressure (which was higher than it should be).
At the end of all this, Mr. B will have a precise diagnosis based on a great amount of additional data, whereas Mrs. A will not. Her diagnosis will be based solely on the answers to the questions her doctor asked her. Mr. B will have targeted treatment, directed selectively towards the disorder that is ruining his life. The cardiologist can explain this in precise detail.
Mrs. A asks her psychiatrist whether, and how, altered serotonin can cause depression. Her doctor tells her that the role of serotonin in depression is still unclear. She adds that because drugs acting on serotonin do improve recovery from depression, this is not evidence that low serotonin was the cause, any more than because a band-aid aids a cut’s healing, the cut is not due to the absence of a band-aid. In fact, she adds, many in the field no longer believe in the “low serotonin causes depression” theory. No one really knows why serotonin-acting drugs (among others) are helpful in depression.
If we were to resurrect a cardiologist from the 19th century and seat him at Mr. B’s consultation, he (it would be a “he”) would be completely amazed at what had happened to his specialty. Moreover, he would have no idea about what he was seeing: The tests and the examination would be outside anything he knew. The diagnosis would have no meaning for him. The treatments would be unintelligible.