Of course it isn’t! The brain mediates our thoughts, emotions and actions, including mental illness. This statement is of course true. But biomedical psychiatry’s claim is that mental illness will be shown to be due to an abnormality in the brain, even that there is considerable evidence already to come to this conclusion. This hypothesis may seem to stand to reason, but it doesn’t. Let me explain.
Abnormalities of the brain can of cause cause mental symptoms. Such is the case for example with a brain tumour. Definite neurological signs may also be present in cerebral disease. Fortunately such organic conditions tend to cause symptoms affecting cognitive functioning that usually allow them to be distinguished from non-organic mental illnesses, like schizophrenia or depressive illness. Primary mental illness, not caused by brain disease, is functional and not structural. It shows through the brain but not in it.
Acknowledging this situation has advantages for psychiatric practice. It should mean that people are not reduced to their brains. They must not be treated as objects. Clinical work needs to be focussed on understanding patients’ histories and mental states and formulating their problems in those terms. Treatment needs to be about supporting them to deal with their problems.
This basic message needs reinforcing in the current mental health system which has become too dysfunctional and fragmented. Psychiatry needs to move on from an outdated belief in mental illness as brain disease.