“Textbook authors are preoccupied with telling the students that psychiatric disorders are hereditary. Obviously, this gives the specialty prestige. It makes it look more scientific to claim that psychiatric disorders are in the genes and that they can be seen on a brain scan or in brain chemistry (see next chapter). But even if it were true, it would have no clinical consequences, as we cannot change our genes.
I shall explain in this chapter why the information in the textbooks about the causes of psychiatric disorders is generally highly misleading.
First, a sobering fact. Many billions of dollars have been spent by the US National Institute for Mental Health (NIMH) on finding genes predisposing to psychiatric diseases and on finding their biological causes. This has resulted in thousands of studies of receptors, brain volumes, brain activity, and brain transmitters.7-231
Nothing useful has come out of this enormous investment apart from misleading stories about what the research showed. This might have been expected from the outset. It is absurd, for example, to attribute a complex phenomenon like depression or psychosis or attention deficit and hyperactivity to one neurotransmitter when there are more than 200 such transmitters in the brain that interact in a very complex system we don’t understand.25 …”
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