It is not possible to diagnose anosognosia in schizophrenic patients on brain scan

von freakoutcrazy

by Critical Psychiatry


As I mentioned in my previous post there has been a clash between Sandra Steingard and E Fuller Torrey about anosognosia in schizophrenia. Where they are both agreed is that it is not possible to use a brain scan to diagnose this condition or even schizophrenia itself. However, it may be difficult to realise this from the brain scan image above taken from the Treatment Advocacy Center’s  backgrounder webpage on pictures of anosognosia, which implies that anosognosia is due to decreased blood flow in the precuneus region of the brain. Sandra Steingard is right to object to this misleading brain overclaim, which is very common in the literature (see eg. previous post).

Despite Fuller Torrey’s accusation, I am aware of the evidence that he cites for brain volume reduction in schizophrenia. However, I do object to his interpretation of this data as evidence of schizophrenia being a brain disease as such and his apparent unwillingness to debate his speculation. Any differences in brain volume are modest and there is an overlap with the normal population. The result is also non-specific as similar findings are found in other psychiatric conditions. Confounding variables such as nutrition and hydration also affect brain volumes. An association does not necessarily imply a causal link, as Fuller Torrey knows, and he should be more cautious in interpreting the data.