Depression Likely Not Caused by a Chemical Imbalance in the Brain – New Study


From The Conversation: “For three decades, people have been deluged with information suggesting that depression is caused by a ‘chemical imbalance’ in the brain – namely an imbalance of a brain chemical called serotonin. However, our latest research review shows that the evidence does not support it.

Although first proposed in the 1960s, the serotonin theory of depression started to be widely promoted by the pharmaceutical industry in the 1990s in association with its efforts to market a new range of antidepressants, known as selective serotonin-reuptake inhibitors or SSRIs. The idea was also endorsed by official institutions such as the American Psychiatric Association, which still tells the public that ‘differences in certain chemicals in the brain may contribute to symptoms of depression.’

Countless doctors have repeated the message all over the world, in their private surgeries and in the media. People accepted what they were told. And many started taking antidepressants because they believed they had something wrong with their brain that required an antidepressant to put right. In the period of this marketing push, antidepressant use climbed dramatically, and they are now prescribed to one in six of the adult population in England, for example.

For a long time, certain academics, including some leading psychiatrists, have suggested that there is no satisfactory evidence to support the idea that depression is a result of abnormally low or inactive serotonin. Others continue to endorse the theory. Until now, however, there has been no comprehensive review of the research on serotonin and depression that could enable firm conclusions either way.”

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  1. “Another area of research has focused on serotonin receptors, which are proteins on the ends of the nerves that serotonin links up with and which can transmit or inhibit serotonin’s effects. Research on the most commonly investigated serotonin receptor suggested either no difference between people with depression and people without depression, or that serotonin activity was actually increased in people with depression – the opposite of the serotonin theory’s prediction.”

    I sort of feel as if depression is likely a ‘brain activity imbalance’ sort of like a muscle imbalance. Just as muscles atrophy with lack of use, parts of the brain go into disuse, which is like atrophy though the cells are still there, though it’s also true that such parts of the brain eventually do start to shrink as well.

    If depressed people have higher serotonin, maybe that’s like the body trying to re-activate certain areas, or like the brain doing the equivalent of compensating for weak muscles by simply flexing them harder. And SSRI’s is like boosting the part of the muscle that causes electrical activity and flexing, rather than lifting weights so that your muscle fibers get bigger or you develop more muscle fibers. E.g., try to force weak muscle fibers to work harder rather than make them bigger.

    But it’s possible SSRI’s tricks the brain into thinking it doesn’t need to start the processes that fix itself. Or, if depressed people have higher serotonin, is that temporary? A temporary response to depression and how the brain tries to recover? Or were they always that way?

    Depending on the answer to that, SSRI’s might go and, when they boost serotonin themselves, they force the body to refrain from starting up the process that assists depression recovery, in order to avoid Serotonin overload.

    I don’t know.

    I think they have not thought to do such studies, have they?

    See, I majored in math and also studied some physics and I was wondering whether it might help for psychiatry to see whether their departments could benefit from networking with mathematicians.

    There is a whole field called “neural networking” that the mathematically inclined really love. And my mathematical intuition as well as study of physics is exactly what makes me inclined to think of the brain in this manner. Indeed, the brain works kind of like how waves work in the study of physics.

    There may well be studies you could even do of brain activity of depressed people, where you can actually figure out quite a lot, if you got the right mathematicians to theorize right about the causes of mental illness, and to test out different theories and see whether they could possibly spot different patterns here or there.

    Of course, one wonders how psychiatrists might react to not fully understanding the math behind their own subject. You either have a mathematical brain, or you don’t.

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    • LivingPast27, That is interesting if they are really anti-inflammatory drugs. I have no science education, really, but I have been concerned, lately, that many of the problems associated with these drugs is that they are using synthetic ingredients that only mimic the brain and instead of giving people these drugs we need to find out individually what would bring, for instance, the serotonin in the brain up without drugs. But then the question might be is it the same for everyone. Could increasing the serotonin, for instance, in one person’s brain actually be harmful, while in another person’s brain, it might be helpful. I don’t know, but, it seems the researchers are not challenged to find the answer. Thank you.

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      • My theory (and not necessarily a correct theory) is that ‘antidepressants’ mechanism of action is through inflammation changes that alter the permeability of the blood brain barrier. I believe my ‘bipolar’ mood disorder is a presentation of changes in inflammation with low inflammation being associated elevated moods and high inflammation being associated with depressed moods. I also believe depression is like a fever and simply a component of a larger immune response. If you think of the ‘fight or flight’ response as your immune system responding to a threat then the path to a medically based cause and eventual treatments.
        Be careful making the mistake that depression has a single cause and generalizing my experience to your own. A virus and a bacteria both cause the immune response of fever but treating the cause of that fever requires two very different treatment protocols.

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  2. How can any “genuine Medicine” NOT be aware after 30 years of usage, that this type of drug has very little value.

    (I remember attending an ‘Event’ a few years ago in Central London where a learned Mental Health Lawyer and Tribunal Judge, stated that if psychiatrists were to acknowledge the effects of psychiatric drugs, they would not be able to prescribe them.

    His actual point was that it was reasonable enough for a Psychiatrist not to acknowledge Psychiatric Abuse).

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  3. When I complained in Ireland about nearly losing my life on psychiatric drugs, a psychiatrist sympathised with me, but stated that this was not just something that happened in Ireland, but in every other country as well.

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  4. There are multiple reasons for depression. Successful treatments depend on knowing the origin of the depressed mood (and if there’s anything else besides simple circumstantial depressed moods) which can very from circumstantial to heavy metal poisoning (plus many things in between)- many of which will NOT respond to antidepressants.

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  5. No specific “thing” causes “depression.” Depression is a state of mind, not a medical entity that can be “caused.” Many things may “lead to” depression, but this research thoroughly disproves that any commonality in serotonin processing or levels has the slightest thing to do with it in a general sense. Researchers need to get a clue and start looking for subgroups who might actually have things in common with each other.

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