Inferences about the biology of schizophrenia

A seminar on schizophrenia in The Lancet says the syndrome "seems to originate from disruption of brain development caused by genetic or environmental factors, or both". Note the use of the word 'seems'. The article is not saying that schizophrenia does originate from disruption of brain development. In fact, as the sentence stands, it's not absolutely clear that the article is saying any more than the tautologous statement that mental illness is due to the brain. Of course it is. And so is our "normal" behaviour.

More specifically, the article makes out that "advances in genomics, epidemiology, and neuroscience have led to great progress in understanding the disorder". The problem is that it does not make any firm inferences about the biology of schizophrenia. The studies it discusses are plagued by so many inconsistencies and confounders that more caution needs to be made about drawing any conclusions about biological abnormalities in schizophrenia. The findings may well be artefacts or of dubious value as far as establishing the aetiology of schizophrenia. The article is misinforming people in this respect.

The authors imply there is less controversy about the issue of the biological origins of schizophrenia now because of these studies over recent years. They do need to recognise the critical challenge to their position.