Depression and low mood: an evolutionary response?

Depression and low mood are unpleasant, undesirable experiences. But what if we actually need them? Here’s an attempt at a positive spin. There’s a long established set of ideas around depression being a necessary evolutionary response system designed to warn us when things are off. A soft reset, if you like. It can also be seen as a way of building resiilience to mitigate future episodes of low mood. We’ve been here before, so we can get through it again. These are the ups and downs and trials of life.

In much the same way that anxiety can be seen as necessary to keep us safe, and even keep us alive, perhaps so can depression. Depression can be considered as an evolutionary mechanism or correction system. It can prompt us to stop engaging in unrewarding, hopeless, or high-risk tasks. Low mood can serve as a signpost to pause, to conserve energy, and recalibrate ourselves away from unhelpful pursuits or unattainable goals, away from being busy for the sake of being busy. One example research study concerns Norwegian farmers and low mood. It highlighted the benefits of sometimes doing nothing, and challenging the nervous human urge towards action. In this specific case, action yielded very limited agricultural benefit in the face of extreme weather conditions. This also makes me ponder on the human compulsion to have business meetings, about meetings, sometimes with no set agenda or purpose or outcomes. As well as the modern human compulsion to infinitely scroll phones: the amusement search task with no end, often with the net result of feeling worse about ourselves and the world. There is a long held value that humans place on being busy. Being busy means we have worth, perhaps that we are making money, staving off financial anxiety, perhaps that we are still searching for a critical truth or opportunity. But of course it is important to be busy, to have occupation and purpose. As with all things, there is a spectrum, and balance is important. Depression as a response to adversity or failure Depression and low mood can be triggered by specific events. Consider bereavement, or not getting a job you dreamed yourself into, or not getting a second date with someone you really liked. Consider two or al three at once Even individually, they each represent loss and pain, and can naturally lead to a short term funk or a long term slump. I am not good enough. I will never be good enough. I will die sad and poor and lonely. Resilience is a word often conflated with adversity. Getting knocked down and getting back up again. There is a broadly promoted concept that ‘only losers quit’, an expectation to keep going and to accept what we have always accepted. Life is hard. Stop complaining and crack on. This can all feel simplified and amplify the pain and guilt and suffering, because sometimes quitting can be a rational and beneficial response to continued adversity and suffering. But it’s not easy and again comes with pain and loss, at least in the short term. Mourning and Melancholia Over a century ago Sigmund Freud published a seminal work titled ‘Mourning and Melancholia’. He said that depression takes two forms. There is ‘mourning’ the loss of a loved one, which is characterised by intense sadness and despair, but usually not guilt, shame or self-reproach.

Then there is ‘melancholia,’ which is typified by intense sadness with feelings of self-recrimination and self-deprecation, a failure of living up to one's ideals or standards. The latter can be rooted in a long established feeling inadequacy or inferiority. Whereas the former is an expression of pain resulting from a very specific trigger, that may shrink or soften with the passing of time. Hopelessness, worthlessness and helplessness are prominent features of depression. If people have a concrete belief that nothing can be changed and negative outcomes can’t be avoided, they can feel worthless and weak. Any effort can feel hard. Negative bias feels easier and more comfortable than any alternative. Control and an acceptance of not having control can also be a factor. Depression as a smoke alarm The smoke alarm principle concerns a need for false alarms, drills and tests in case of an actual fire. There is a need to understand when alarm is rational and necessary, and when it’s not. When the cost of a defensive response (like depression, low mood, or anxiety) is low compared to the catastrophic cost of missing a real danger. Evolutionary responses are biased towards a low trigger. Low mood acts as a signal to rest, conserve energy, and maybe give up a habit or behaviour. Although this challenges commonly held ideas around adversity responses, that resilience is always good, that ‘only losers quit’. Sometimes we need to draw a line and move on from unhelpful behaviours, otherwise our overall health and survival can be compromised.