Noting that more people die from suicide than car accidents in the U.S., and the majority of those suffer from depression, The Atlantic explores a theory put forth in a recent paper linking depression to immune system activation and associated behavioral responses. “The basic idea is that depression and the genes that promote it were very adaptive for helping people – especially young children – not die of infection in the ancestral environment,” the paper’s authors comment, by activating a set of protective behaviors – such as social withdrawal – in response to stressful events in the wild that may expose us to risk of infection.
Of further interest:
The evolutionary significance of depression in Pathogen Host Defense
Note from Kermit Cole, “In the News” editor;
Though the article explores the concept of depression as linked to immune system response, as an evolved self-protective response that reduces the risk of infection following injury or stress, I also wonder about the concept of “inclusive fitness” in relation to this theory; that we have evolved to limit the risk to others when we ourselves are infected. I wonder whether, when we feel ourselves to be a liability in some way (perhaps having come by this feeling as a result of messages we received from family, etc., there may in fact be an evolved response that triggers isolative or suicidal behaviors; that, in fact, “altruism,” as demonstrated in much behavioral research of mammals, extends to removing ourselves out of a sense of fairness (also well-documented in primate research).
If there is anything to this thought, it would suggest an entirely different mode of interacting with the suicidal impulse; one of respect and exploration, rather than fear and censure.