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The Benefits of Depression

hmarcia's picture


The Benefits of Depression I recently read an article that proposed that practically everything we do and feel comes from evolution; in other words, we act the way we act because it contributes to our abilities to produce offspring. With this hypothesis in mind, I decided to test it with a very common mental condition: depression. When I think about depression, words such as sad and blue come to mind, but depression obviously entails more than just the normal case of the “blues”. Depression is defined as; “a condition of general emotional dejection and withdrawal, and or sadness greater and more prolonged than that warranted by any objective reason” (1). It is a mental condition that affects approximately 20.9 million adults in the United States each year, and those with depression often suffer consequences that negatively affect their lives, but why does depression exist (2)? What is the biological evolutionary reasoning behind depression? Society often stigmatizes those that experience depression by labeling them as “sick”, but is it necessarily a sickness? We will need to look at the chemical and biological reactions in that occur in the brain, at evolutionary theories about depression to explain the reasons for the condition, and to figure out if it is indeed a benefit to experience. The biological and chemical factor is often cited as an important factor in the development of depression. The biological factors that aid the development of depression involve chemicals in the neurons in our brains. Chemicals called neurotransmitters, which function as messengers between the nerve cells, are considered to be the culprits in depression (3). There is a strong coloration between the three main monoamine neurotransmitters in the brain (dopamine, norepinephrine, and serotonin) and depression (4). Research concludes that symptoms of depressions depend on the levels of the three monoamine neurotransmitters in the brain; the lower the level of the three monoamine neurotransmitters and the more likely it is to exhibit symptoms of depression (4). From these observations, two very important theories explaining the origins of depression came about. The first theory, “catecholamine theory”, emerged in the 1960 and proposes that depression stems from a lack of norepinephrine in some brain circuits (3). A large number of studies support this hypothesis, but these studies also showed that changes in the levels of norepinephrine did not cause depression in everyone. From this hypothesis, the second theory emerged (3). The “permissive hypothesis” proposes that the reduction of serotonins in the brain leads to reductions in the levels of norepinephrine, and the low levels of norepinephrine leads to the symptoms of depression (3). Although there are three neurotransmitters, the “permissive hypothesis” makes serotonin the most important neurotransmitter in the brain (3). It is for this reason that most anti-depressants medications contain high levels of serotonin in an effort to artificially increase the levels of serotonin in the depressant’s brain. Understanding the biological factors that cause depression makes understanding the evolutionary reasons for depression clearer. The phrase “the survival of the fittest” highlights Darwin’s theory of evolution, but where does depression fit in with this idea of “the survival of the fittest”? Do the “fittest” experience bouts of depression? In the last couple of years, scientists have concluded that despite the costs of depression, there does exist real benefits. A recent study proposes the idea that those benefits can be found in the analytical thinking processes of those depressed. Isolation and the inability to enjoy daily activities are common symptoms of depression, and the study found that depressed individuals often think intensely about their problems (5). With both of these combined, you have a person who is only focused on the problems that they currently have. By becoming depressed, the mind forces the individual to pay attention to major problems that might possibly endanger the life of the depressed person and need urgent attention. By being depressed, the person isolates himself from anything that might possibly distract him from thinking about his problems. Other studies have concluded that those depressed often develop strong analytical thinking skills. For example, those depressed will often dwell on a very complex problem, break it into smaller components, and further consider those smaller components (5). By focusing on the smaller components of the big problem, the depressed person is able to better analyze the problem. All of this analyzing requires uninterrupted thinking and leads to the characteristics that we might view as negative. For example, the loss of appetite, although considered a negative symptom of depression, is in fact a good one because chewing might in fact interfere with the brain’s ability to think (5). Studies have also shown that people suffering depression are better at resolving social dilemmas because by being able to better analyze, they are able to understand the costs and benefits of the different options that they might take in the social dilemma (5). There are positive reasons for suffering depression, and in terms of evolution it is a very positive one. Society might still stigmatize those suffering from depression as “sick”, but newer research and studies conclude that depression is not necessarily some sort of sickness. More and more, it appears to be a sort of process that we all need to go through at some point in our lives in order to develop a clearly understanding of our problems. Depression serves as a tool for our mind to force us to deal with problems we perhaps do not really want to. It appears that our minds look out for our better interest by forcing us to become depressed when there are major problems. No one is able to decide when they will be depressed and when not be depressed. If this is the case, then want agents are at play besides the chemicals, the environment that might be causing the problems, or us? What is sparking that depression? Is our subconscious looking out for our interests by causing depression when it deems necessary? These questions remain unanswered for now but all current findings seem to suggest that with proper help, most will emerge from depression better than before.




Paul Grobstein's picture

depression as an evolutionary adaptation?

Very intriguing set of issues, well worth thinking more about.  Is there actually evidence that "most will emerge from depression better than before"?  In what ways?  If one follows this line of argument, ought one to treat depression pharmacologically or not?  For more on these issues, see Exploring depression