The thing is, clinical [endogenous] depression strikes the successful and the unsuccessful alike - it's a biochemical imbalance, not a psychological reaction.
it's a biochemical imbalance, not a psychological reaction
To call depression a "chemical imbalance" is what physicians, compassionately, tell their patients to encourage them to take their medicines. But the doses of lithium, the best evidenced drug for depression, that are in the therapeutic range are many times higher than the natural level of lithium that occurs in any healthy untreated human being, and perilously close to the toxic dose.
The current view is that depression strikes people who have a genetic vulnerability (that much would be either biochemical or structural, perhaps a different vulnerability in different patients) who also experience certain kinds of environmental stress (perhaps not always the same kinds of stress for all patients with the same underlying vulnerability). That medicines relieve depression--as some plainly do for many patients--doesn't prove that what the patients had beforehand was a lack of those medicines, or even exactly an imbalance of the brain chemicals most influenced by those medicines. The most effective treatment for depression generally appears to be a both-and of prescribed medications and evidence-based cognitive therapy.
To call depression a "chemical imbalance" is what physicians, compassionately, tell their patients to encourage them to take their medicines. But the doses of lithium, the best evidenced drug for depression, that are in the therapeutic range are many times higher than the natural level of lithium that occurs in any healthy untreated human being, and perilously close to the toxic dose.
The current view is that depression strikes people who have a genetic vulnerability (that much would be either biochemical or structural, perhaps a different vulnerability in different patients) who also experience certain kinds of environmental stress (perhaps not always the same kinds of stress for all patients with the same underlying vulnerability). That medicines relieve depression--as some plainly do for many patients--doesn't prove that what the patients had beforehand was a lack of those medicines, or even exactly an imbalance of the brain chemicals most influenced by those medicines. The most effective treatment for depression generally appears to be a both-and of prescribed medications and evidence-based cognitive therapy.