A question recently posed by my psychiatrist: what is the evolutionary advantage to feelings, specifically bad feelings like depression or anxiety?
I should first note that my doctor strictly adheres to the methodology of cognitive behavioral therapy. He believes that all emotions have triggers, and finding those triggers are the key to good health. He also believes that the difference between myself with my mental illness, and another person who does not have a mental illness might simply be varying degrees of ‘born-with’ talents and abilities. Maybe my anxiety eats me alive not because I suffer from higher anxiety levels, but because I cannot deal with normal levels like most people.
I share most of those beliefs and I have written essays basically breaking down those views. So while they might seem extreme and dismissive of mental illness, it is actually empowering. He is still saying there is a difference, a born with difference, and he isn’t saying that difference isn’t physical/ mental illness. But what he is saying is that we are not permanently irrevocably broken. He also believes that therapy is the key, not medication. A view I have had since I was first diagnosed. These are just a few of the reasons I enjoy my shrink.
So what is the evolutionary advantage of feelings?
First, there doesn’t have to be one. Clearly there was an advantage to emotion. Fear kept us safe, anger propagated our dominance, love expanded and enhanced the species. It is possible that there were byproducts of having such advanced emotions, and those took the form of anxiety, depression, and self-doubt. Kinda like heart disease is the byproduct of a metabolism that is extremely good at storing fat in preparation for starvation. That is the easy explanation.
But what if depression and anxiety had their own advantage?
When he asked it, I probably had a queer look on my face. He stared at me, I think looking for an answer but I had none. Maybe anxiety kept us safe of things we didn’t know we should be afraid of? Like an extension of fear? Maybe people who were depressed stayed in bed all day and didn’t catch whatever virus was flying through the village? I had no idea what he was talking about.
He told me that one known cause of depression was a mutated gene that produces a lack of a neurotransmitter called NPY. The interesting thing that has been discovered is that when acute stress is forced upon a person with the mutated gene, the neurotransmitter releases an agent that both causes depression and boosts the immune system, especially in children. Acute stress that might cause depression today might be losing your job, but thousands of years ago it could come from a severe injury or who knows.
NPY has been shown to be hereditary, and may be the hereditary link often assumed in depression and mental illness in general. But it would also provide for a child that was more likely to fend off infection. There are other theories he told me about, going and laying in bed would conserve your energy for your immune system. And he actually did say that staying to yourself prevented you from catching a communicable disease.
Maybe he is right, maybe this research is right, I have no idea. Depression seems like a totally maladaptive consequence of some other thing happening. The fact that suicide kills more people than war and murder combined; or that it is the number one cause of violent death in the United States. Especially that it takes mostly the young, as the number one killer of people under the age of 25. It seems impossible to find a silver lining here.
But there is one. It appears as if evolution decided that it would spare the lives of the young, by increasing their immune systems, only to increase their suffering as adolescents and young adults. Mental illness kinda works that way too, I think. There really is nothing out there that makes it completely better. And sometimes it feels like you are trading off a bad thing for a different bad thing down the road. But at least you keep heading down that road a little longer.