Perhaps these conditions aren't mental disorders at all (anxiety, depression, PTSD)

Alison Escalante, Researchers Doubt That Certain Mental Disorders Are Disorders At All, Forbes, Aug. 11, 2020.

What if mental disorders like anxiety, depression or post-traumatic stress disorder aren’t mental disorders at all? In a compelling new paper, biological anthropologists call on the scientific community to rethink mental illness. With a thorough review of the evidence, they show good reasons to think of depression or PTSD as responses to adversity rather than chemical imbalances. And ADHD could be a way of functioning that evolved in an ancestral environment, but doesn’t match the way we live today.

Adaptive responses to adversity 

Mental disorders are routinely treated by medication under the medical model. So why are the anthropologists who wrote this study claiming that these disorders might not be medical at all? They point to a few key points. First, that medical science has never been able to prove that anxiety, depression or post-traumatic stress disorder (PTSD) are inherited conditions.

Second, the study authors note that despite widespread and increasing use of antidepressants, rates of anxiety and depression do not seem to be improving. From 1990-2010 the global prevalence of major depressive disorder and anxiety disorders held at 4.4% and 4%. At the same time, evidence has continued to show that antidepressants perform no better than placebo.

Third, worldwide rates of these disorders remain stable at 1 in 14 people. Yet “in conflict‐affected countries, an estimated one in five people suffers from depression, PTSD, anxiety disorders, and other disorders,” they write.

Taken together, the authors posit that anxiety, depression and PTSD may be adaptive responses to adversity. “Defense systems are adaptations that reliably activate in fitness‐threatening situations in order to minimize fitness loss,” they write. It’s not hard to see how that could be true for anxiety; worry helps us avoid danger. But how can that be true for depression? They argue that the “psychic pain” of depression helps us “focus attention on adverse events... so as to mitigate the current adversity and avoid future such adversities.”

If that sounds unlikely, then consider that neuroscientists have increasingly mapped these three disorders to branches of the threat detection system. Anxiety may be due to chronic activation of the fight or flight system. PTSD may occur when trauma triggers the freeze response which helps animals disconnect from pain before they die, and depression may be a chronic activation of that same freeze response.

The article linked in the first paragraph: Kristen L. Syme, Edward H. Hagen, Mental health is biological health: Why tackling “diseases of the mind” is an imperative for biological anthropology in the 21st century, Yearbook Phys Anthropol. 2020;171 (Suppl. 70):87–117, https://doi.org/10.1002/ajpa.23965

Abstract: The germ theory of disease and the attendant public health initiatives, including sanitation, vaccination, and antibiotic treatment, led to dramatic increases in global life expectancy. As the prevalence of infectious disease declines, mental disorders are emerging as major contributors to the global burden of disease. Scientists understand little about the etiology of mental disorders, however, and many of the most popular psychopharmacological treatments, such as antidepressants and antipsychotics, have only moderate‐to‐weak efficacy in treating symptoms and fail to target biological systems that correspond to discrete psychiatric syndromes. Consequently, despite dramatic increases in the treatment of some mental disorders, there has been no decrease in the prevalence of most mental disorders since accurate record keeping began. Many researchers and theorists are therefore endeavoring to rethink psychiatry from the ground‐up. Anthropology, especially biological anthropology, can offer critical theoretical and empirical insights to combat mental illness globally. Biological anthropologists are unique in that we take a panhuman approach to human health and behavior and are trained to address each of Tinbergen's four levels of analysis as well as culture. The field is thus exceptionally well‐situated to help resolve the mysteries of mental illness by integrating biological, evolutionary, and sociocultural perspectives.

FWIW, this line of thought is consistent with my sense of why I enter a melancholy phase at the beginning of the year. Here's three paragraphs from a post where I talk about that:

I do think my mood follows my productivity, or vice versa, and that’s what’s interesting. David Hays once conjectured that melancholy (aka depression) is the price you pay for large-scale reorganization or the sort implied by creativity. “Reorganization” is a term of art from William Powers’s account of the mind. It is so deeply embedded in that theory that there is, alas, no easy gloss.

Start out by thinking of learning. When you learn, your mind is also reorganizing on a large scale. Now think of mourning as well. When you mourn the loss of someone close you have to reorganize your mind for life without them. You don’t actually learn anything, but you have to figure out how to function in those situations where you would have go to that person. It’s unlearning.

In order to be creative you must first unlearn on a large scale. That is accompanied by melancholy. That, on this view, accounts for those troughs in my intellectual output, which is mostly though not entirely through New Savanna. That creates some “slack” in the system. Once enough unlearning has taken place I can then think new thoughts and my productivity goes up. When the slack has been used up, it’s time for more unlearning./blockquote>