Psychologists Think They Found the Purpose of Depression

Depression is pervasive: In 2015, about 16 million - or 6.7 percent of - American adults had a major depressive episode in the past year. Major depression takes the most years off of American lives and accounts for the most years lived with disability of any mental or behavioral disorder. It is also expensive: From 1999 to 2012, the percentage of Americans on antidepressants rose from an estimated 6.8 to 12 percent. The global depression drug market is slated to be worth over $16 billion by 2020.

The National Institute of Mental Health defines a major depressive episode as "a period of two weeks or longer during which there is either depressed mood or loss of interest or pleasure, and at least four other symptoms that reflect a change in functioning, such as problems with sleep, eating, energy, concentration, and self-image" This falls in line with what Matthew Hutson, in a new feature for Nautilus, describes as the disease model of depression: that depression is
"a breakdown, a flaw in the system, something to be remedied and moved past" In his compelling and challenging piece, Hutson profiles several researchers who advance an argument that depression can serve a possibly positive purpose in the lens of evolution. But rather than deifying evolution and trying to scry out what it meant for us, let’s focus on what’s more immediately useful for lived human lives today: that, in some circumstances, depression may be, in the arc of a life, yielding of insights and personal meaning. All of this is in no way meant to minimize the suffering that depression can cause but to suggest the uses that it may serve.

At the center of Hutson’s piece is Paul Andrews, an evolutionary psychologist at McMaster University in Canada. Andrews argues that depression may be "an adaptation for analyzing complex problems" He sees it in the condition’s bouquet of symptoms, which include "anhedonia" or an inability to feel much pleasure; people who are depressed ruminate frequently, often in spirals; and they get more REM sleep, a phase associated with memory consolidation. This reflects an evolutionary design, the argument goes, one that’s to, as Hutson summarizes, "pull us away from the normal pursuits of life and focus us on understanding or solving the one underlying problem that triggered the depressive episode" Like, say, a "failed" relationship. The episode, then, is a sort of altered state, one different from the hum of daily life, one that’s supposed to get you to pay attention to whatever wounding led to the upset. For example, 80 percent of subjects in a 61-person study of depression found that they perceived some benefit from rumination, mostly assessing problems and preventing future mistakes.

For now, Andrews’s "analytical rumination hypothesis" is just that, a hypothesis, a term that combines the Greek hypo (under) with -thesis (placing). It’s a concept, an observation, one that acts as a structure for further inquiry. Still, already, there is something very powerful, and even actionable, in reconceptualizing (some) depressive episodes as having a function, as presenting a quest toward understanding for the sufferer to undertake. Other research helps to refract the light being shined here: Laura King, a psychologist at the University of Missouri, has spent a couple decades studying people’s experiences of meaning in life, and she told me in an interview at this year’s Society for Personality and Social Psychology meeting that the meaning people derive from difficult experiences depends not on the amount that they’re suffered, but the extent of reflection or meaning-making  they’ve done on what prompted a given nadir. Following this logic, if the job of a depressive episode is to figure out what’s gone awry, what emotional knots need to be untangled, what attachment patterns need to be identified and addressed, then antidepressants are an incomplete treatment, just like you wouldn’t prescribe Percocet to a heal a broken ankle without also supplying a cast.

There are even larger, structural issues around the culture and industry of mental health at work here: If the healing of depression requires not just an alleviation of symptoms but a reworking of patterns within a person’s psychology, that’s a deeply subjective rather than objective process, meaning that the scientific method may have difficulty accessing it, and since it’s not objective, it’s perceived as less real or true, since it resides in your interiority, not out there in the readily testable world. Also, therapy - whether cognitive behavioral or psychoanalytic - requires lots of money and lots of time and is not, to say the least, well-supported by insurance companies in the U.S.

Still, this framing of depression as a space for reflection is empowering, and lends a degree of agency to the person being pressed down. Like anxiety, depression might be trying to tell you something. The language of therapeutic traditions is useful: a Jungian analyst would describe depression as katabasis, an Ancient Greek word for descent. Like Orpheus heading to Hades or Luke Skywalker in the swamps of Dagobah, it’s a journey into the underworld, where the adventurer is to "go through the door …. immerse himself in the wound, and exit from his old life through it" like Robert Bly writes in Iron John. Since it is subjective, the problems and solutions will be personal - of the person and their particular psychological history - and thus demand the individualized understanding of the sufferer of depression, perhaps with the assistance of a skilled therapist. That’s another theme: While disengagement from emotionality characterizes depression and other disorders, engagement with one’s inner world looks to to be the way out. Put more poetically: You exit through the wound.

"Most episodes of depression end on their own - something known as spontaneous remission" Vanderbilt psychologist Steven Hollon tells Nautilus, noting that the depression-as-adaptation narrative may explain why. Indeed, “cognitive behavioral and problem-solving therapies may work precisely because they tap into and accelerate - in a matter of weeks - the very processes that have evolved to occur over the space of months" he added. Katabasis leads to catharsis; not coincidentally, there’s a shared theme in the personal narratives of people who reach midlife with a sense of well-being and generativity toward others: redemption.