What is depression? [an umbrella term]

Joanna Thompson, The Cause of Depression Is Probably Not What You Think, Quanta Magazine, Jan. 26, 2023.

Thompson opens by discussing a recent literature review that cast strong doubt on the idea that depression is the result of serotonin deficiency. She then moves through other chemical theories, to genetics, neural wiring, and inflammation, ending up with:

Increasingly, some scientists are pushing to reframe “depression” as an umbrella term for a suite of related conditions, much as oncologists now think of “cancer” as referring to a legion of distinct but similar malignancies. And just as each cancer needs to be prevented or treated in ways relevant to its origin, treatments for depression may need to be tailored to the individual.

If there are different types of depression, they may present similar symptoms — such as fatigue, apathy, appetite changes, suicidal thoughts, and insomnia or oversleeping — but they might emerge from completely different mixes of environmental and biological factors. Chemical imbalances, genes, brain structure and inflammation could all play a role to varying degrees. “In five or 10 years, we won’t be talking about depression as a unitary thing,” Sen said.

To treat depression effectively, medical researchers may therefore need to develop a nuanced understanding of the ways it can arise. Nemeroff expects that someday the gold standard for care won’t be just one treatment — it will be a set of diagnostic tools that can determine the best therapeutic approach to an individual patient’s depression, be it cognitive behavioral therapy, lifestyle changes, neuromodulation, avoiding genetic triggers, talk therapy, medication or some combination thereof.

Sounds like we're getting somewhere, at last.