Mental Illness or an Adaptation?
Is there an adaptational role to brain-based disorders
Posted Sep 06, 2014
A Caucasian, otherwise healthy 50-year-old man is struck with depression. He has never experienced depression before. A lawyer by occupation, with a family and a partnership at a firm, he is baffled by why he is feeling depressed and wants a prescription to fix his life.
I can readily think of many other patients and friends who’s lives are seemingly great. Decent jobs, stable marriages, kids in college and yet they are on antidepressants. Are they all depressed for no good reason or is the depression an appropriate evolutionary response to life’s circumstances?
I start talking to the patient, as he casually mentions other partners at the firm, their kids, young wives and some tennis friends. He says his marriage is great and he has never thought about leaving his wife. “Well, what do you think about?” He is “very depressed, has everything in perfect order and cannot understand the reasons for depression.”
Ever since Freud, mental disorders have been divided into neuroses such as panic, anxiety, and depression, which are considered to be less severe as opposed to something like schizophrenia, which is more challenging and is accompanied by other symptoms of paranoia, delusions and hallucinations. At first glance, we might think that schizophrenia is an anomaly, as it only occurs in about 1 percent of the general population. It is obviously a situation where the mind has done a major hiccup and the brain has become ill. But how does this mistake occur?
Research shows that many genes are involved in the disease of the brain such as schizophrenia, although there does seem to be a familial link. If one identical twin has been diagnosed with schizophrenia, the other twin is at a higher likelihood for the condition. This correlation does not however mean that both twins are destined to have the disorder.[i] Only about 60% can be explained through genetic linkage, which leaves another 40% to be accounted for by other factors: environment, chance, etc.[ii]
Psychiatrists have now speculated for sometime around advantages to schizophrenia. If the prevalence of the disorder is any indication, this might suggest an evolutionary adaptation. One group of researchers have suggested that schizophrenia makes people more resistant to outside viruses and stress as opposed to people without it. Perhaps a mind that is psychotic is trying to escape and disconnect from social pressures in a world largely driven by social interconnectedness.[iii] In an attempt to deal with stress, the mind escapes into psychosis. This view, perhaps more sympathetic than most literature might suggest, examines the brain and its disorders as a reasonable adaptation given life’s circumstances. It is a predictable human maneuver to escape a situation if consistently faced with failure to achieve biological goals.
This discussion around an adaptational role of brain-based disorders is interesting, but does not help those individuals suffering and crippled with uncertainty. The depressed man in the example earlier is a case and point. His depression is real and might even make some sense, but what can he do besides medication or simply waiting on life’s circumstances to change? Paul Gilbert and colleague Steven Allan maintain that feelings of depression are correlated with feelings of being trapped.[iv] Indeed there is a positive relationship between depression in those who have either experienced defeat or have a perceived sense of defeat. So it would make sense then, that our patient might be struggling with some perceived sense of defeat, perhaps an interpersonal issue between a colleague or a friend. The brain has simply learned to adapt to lower moods to adjust to trying times.
As I think about my own personal goals, I am struck by how wisely my brain adapts. If I submit a book proposal and it gets rejected a number of times, how do I cope? What I get initially is a sense of hopelessness, worthlessness, pessimism and little energy to go on. What are my alternatives? Give up and feel better? But that’s the problem. I cannot give up. It is just as unnatural for me as not drinking water after a 40 minute run. My body is dehydrated and needs water, much the same way my brain needs to feel a sense of accomplishment with my life’s goals. It can be argued then, that depression is an adaptational strategy and a regulatory motivator for humans. A positive mood indicates motivation and hope, and negative mood indicates lack of hope. This mechanism is brilliant and is ingrained into our genes. It is the same mechanism that gets bears to hibernate over the winter months and forage in the spring and summer.
In treatment, I have found it essential to ask patients questions beyond the standard set: “When did you first notice yourself getting depressed?” “How are you feeling now?” “What is your appetite like?” or “Have you ever thought of hurting yourself?” Beyond those questions lie those personal questions that touch on the depth of human purpose. “Are you pursuing a life goal that you cannot seem to reach?” and “Are you afraid of the possibility of losing something that is vital to your life and daily functioning?” The answer to eradicating symptoms lies in the riddle of human happiness and purpose. By considering another mechanism of influences, we consider another source to mental pathologies.
The now traditional Western psychiatric response to depression, anxiety, and psychosis is medication. Medication can calm the mind and change the brain chemistry enough to give patients a shot at a “normal” life. In other words, human condition of the brain in Western culture is treated as a disease, a malfunction and a system that has to be tightly regulated to function well. Yet disorders come in all sorts of forms, are so global, that to believe in only one idea of what makes people ill or well means to ignore other influences that might contribute to a person’s outlook on life. Those influences could have been thousands of years in the making and a part of our genomic code, or could have been as recent as some environmental stressors. Taking this view can tip the standard of care to instead of trying to make everyone logical, rational and orderly, to simply helping someone regain a sense of balance and in particular, helping those who are living with mental disorders regain a sense of purpose.
[i] McGuire, M., and Troisi, A. (1998) Darwinian Psychiatry. Oxford, Oxford University Press
[ii] Portin, P., and Alanen, Y. (1997) “A critical review of genetic studies of schizophrenia II. Molecular genetic studies.” Acta Psychiatrica Scandinavica 95: 73-80
[iii] Crow, T.J.A. (1995) “A Darwinian approach to the origins of psychosis.” British Journal of Psychiatry 167: 12-25
[iv] Gilbert, P., and Allen, J.S. (1998) “The role of defeat and entrapment in depression: An exploration of an evolutionary view.” Psychological Medicine 28: 585-598