“DEPRESSION IS DUE TO A CHEMICAL IMBALANCE”

The most commonly used antidepressant drugs increase the availability in the brain of a chemical called serotonin. Whatever the rights and wrongs of the drugs (some credit the drugs for saving their lives, while critics fear the overmedicalisation of emotional problems that have complex roots), their rising use has fed the notion that depression is caused by some kind of chemical imbalance in the brain that requires correction.

The reality is that most psychiatrists believe that the chemical imbalance idea is a gross oversimplification. Part of the issue is that it’s based on flawed logic. Just because these drugs increase serotonin levels, it doesn’t mean that a lack of serotonin is the cause of depression (after all, your headache is not caused by a lack of paracetamol). Beyond that, post-mortem research has failed to show that people with depression have lower levels of serotonin, and studies that have artificially lowered people’s serotonin levels have not induced depression. The truth is that there is no psychiatrist or neuroscientist who could honestly say what the healthy or correct levels of brain chemicals should be.

Many mental health campaigners have embraced the chemical imbalance idea, believing that it will help to reduce stigma by showing that depression has a clear physical cause. Sadly, if anything, biological explanations of mental illness seem to have increased stigma, perhaps because they cause people to perceive mental health conditions as being more fundamental to the sufferer and more difficult to treat.