Am I genetically destined to be depressed?

Hello Mark,

I think you should be able to throw light on the subject of depression or, to be more precise, the subject of chemically-based depression. What is the nature of this kind of depression?

As far as I understand, these cases are literally caused by an imbalance of brain chemistry. Is it genetic? If so, I gather that it should be present from a very early age and not just suddenly kick in when you are much older. How severe are these imbalances and is it possible to attain a decent quality of life if afflicted by one?

The reason I am inquiring about this is because I am (perhaps unreasonably) more than a little worried that I may have something like this, although it does seem a little unlikely. I was a very healthy child and my problems with mood didn't start until certain events when I was a teenager. Neither of my parents (or their parents, for that matter) suffer from any mood disorders. Also, I've never been in a situation where my head could have received any physical damage.

I'd also be interested to know how much, exactly, do you need to worry in order for the sleep imbalance of depression to occur? Is dwelling on a particular source of worry sufficient to disrupt sleep or should one worry about a plethora of issues for the REM state to begin to go rampant? What I mean is, do all the individual emotional arousals have to be discharged in REM sleep even if the worrying has been about one and the same subject matter? Do all the arousals that haven't been 'cleared' during the day have to be dreamed out when you sleep at night?

I look forward to hearing from you.

Jesse

This question was submitted by 'Jesse'

Mark says...

Hello Jesse,

The medical model of depression has certainly taken off. The idea was that certain people (about one in three) are genetically at risk or even destined to depress. The idea is that serotonin, a neurotransmitter found in the brain (but more so in the body), has to do with depression and when we have too little, we become depressed. So where did the idea about serotonin and depression come from?

The serotonin/depression connection was first put forward by a Dr George Ashcroft in the 1950s, who thought he had discovered lowered levels of serotonin in the brains of people who had committed suicide. Later experiments using better investigative techniques and equipment found no lowered serotonin in the brains of people who had committed suicide. Dr Ashcroft, as an honourable scientist, dropped his old serotonin hypothesis. But the idea, as we all know, stuck, despite the fact that no link has ever been found between depression and 'faulty brain chemicals'.

And it's even been found that artificially lowering serotonin in people's brains doesn't make them depressed. Antidepressants work in relieving symptoms in some people (about a third of people who consume them), but that isn't significantly better than a placebo response. Check out 'Are Your Brain Chemicals All Wrong?' for more on this.

Of course, billions of antidepressant products are sold worldwide, SSRIs are blockbuster drugs, and to sell such vast quantities of anything, a plausible reason for antidepressants needs to be given. 'Mood disorder' was a term dreamed up not by psychologists or psychiatrists, but by marketing agencies to sell their 'mood stabilizers'. (See 'Am I bipolar?'.)

However, some SSRIs do seem to work in decreasing REM-rich dream sleep and we know depressed people dream much more when they are depressed. Side effects of some SSRI antidepressants include anxiety, anger, and even suicidal ideation (and possibly acts of suicide).

So if we look at the cycle of depression, we can see that dreaming serves the purpose of 'switching off' emotionally arousing unfulfilled fears and worries. But if someone is loaded with many worries and fears and isn't actively problem solving them to 'switch them off', then they will over-dream and fall into the exhaustion of depression that over-REMing leads to.

But if some drugs diminish dream time, now a person may be having lots of very negative feelings that are no longer being 'numbed' or temporarily deactivated by the dreaming and so feel the full force of their anger, fear, or suicidal feelings, but now they have more energy (because over-dreaming is no longer sucking away their motivation and energy) to actually carry out negative actions.

Your brain chemicals are not wrong, Jesse.

Some people may be more prone to worry, regret, guilt, rumination, and introspection and churn things around in their own minds. But you can learn to do this less and pursue strategies that will help calm your limbic system, the emotional parts of your mind, and encourage healthy behaviours so you can meet your primal human needs in life.

As to the second part of your question. Most of us worry sometimes. It seems to be the time and the intensity of that worry that overload REM when we sleep. If you constantly worry about one thing, then that can certainly overload dream sleep, leading to a loss of restorative slow wave sleep. The more you actively problem solve worries – either by learning to feel and think about them so they no longer are worries or by actually finding practical solutions where you can – and the more you occupy yourself, thereby having less time to ruminate, the more you will normalize the REM/deep sleep balance of sleep and stay away from depression.

I hope my answer has proved helpful in some way.

All my best,

Mark