Peter Simons reports for Mad in the UK:
“In June, Joanna Moncrieff and others had appeared to put the final dagger into the low serotonin theory of depression (the so-called ;chemical imbalance’ theory). They reviewed fifty years of research into the theory and found no good evidence to support it. Many prominent psychiatrists even responded by noting that this was nothing new; that hypothesis had been put to bed long ago.
But like a ghost that just won’t disappear, a new study claims to have “clear evidence” that low serotonin is linked to depression. In The Guardian, the lead authors touted the breakthrough nature of their finding:
‘This is the first direct evidence that the release of serotonin is blunted in the brains of people with depression,’ said Prof Oliver Howes, a consultant psychiatrist based at Imperial College and King’s College London, and a co-author. ‘People have been debating this question for 60 years, but it’s all been based on indirect measures. So this is a really important step.’
This is a statement, once the study data is analyzed, that can best be described as having been plucked from thin air. Or, in science terms, plucked from a lone data point arising from a depressed patient that stood in contradiction to the rest of the data that failed to find any serotonin abnormalities in the 11 depressed patients. The one outlier is being used to falsely claim that the release of serotonin is blunted in the brains of people with depression, as though that were an abnormality characteristic of the disorder. (If you include five additional depressed patients with Parkinson’s disease, then you can say that the researchers relied on two data points—from a group of 16 depressed patients—to make their false claim.) …”
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