What really causes depression

‘There is nothing either good or bad, but thinking makes it so.’

William Shakespeare.

Staying positive is a daily challenge that requires a certain amount of focus and attention, and energy.

For evolutionary survival reasons, our brains are hard-wired to look for and focus on threats. This survival mechanism served us very well when we lived on the savannah and had to hunt for our food. But there has been a price to pay for this strategy – this mechanism can also be a source of pessimism and negativity because of the mind’s inbuilt tendency to wander until it finds a threat. This often magnifies our perception that things may be about to go badly wrong.

Negative thoughts and emotions are bad for your health – numerous studies have shown that optimists are physically and psychologically healthier than pessimists.

Martin Seligman at the University of Pennsylvania, together with researchers from Dartmouth College and the University of Michigan, worked on a study that followed people from age 25 to 65 to see how their levels of pessimism or optimism influenced their overall wellbeing. The researchers found that pessimist’s health deteriorated far more rapidly as they aged.

Researchers at the Mayo Clinic in the US also found that optimists have lower levels of cardiovascular disease and longer life-spans. Although the exact mechanism through which pessimism affects health hasn’t been identified, further research at Yale University and the University of Colorado found that pessimism is associated with a weakened immune response to tumours and infection.

As if that wasn’t bad enough, researchers from the University of Kentucky injected optimists and pessimists with a virus to measure their immune response – and they found that optimists had a much stronger immune response than pessimists.

But having a positive outlook on life doesn’t just affect your health – it also affects your performance. In one study in particular, researchers measured the degree to which insurance salespeople were optimistic or pessimistic in their work. Optimistic salespeople sold 37% more policies than their pessimist counterparts, who were also twice as likely to leave the company during their first year of employment.


When human brains have nothing else to do, they think.

The ability to reminisce about the past is important for happiness. Anxiety on the other hand, is like having someone you don’t like looking over your shoulder and constantly telling you you’re doing things wrong. What would you do? You’d tell them to get lost!

People who suffer from depression are less able to remember good times. They have fewer, less detailed and less vivid positive memories, and suffer general difficulty recalling the past.

Even if you’ve practiced meditation, you will still get odd thoughts popping into your head every few seconds. When brains are not engaged in any specific thought process, they inevitably start to wander, either reflecting or planning.

Thinking about what’s happened or what could happen, is such a central part of the human condition that neuroscientists now call it the brain’s ‘default-mode.’ In effect, we piece together bits of our life stories, past, present and future. While there is still some discussion about this, neurologists generally see it as a healthy thing to do.

But there’s one particular way the brain thinks that psychologists say can be destructive – not because all the stories we tell ourselves are helpful, but because some can be self-limiting, even self-destructive.

People tend to take their thoughts to be real and objectively true, but in contrast to tangible things – such as chairs and computers – thoughts are just… thoughts – intangible, fleeting, and sometimes unreliable.

We spend our lives so immersed in our own opinions about people, places and things –including ourselves – that we often mistake what we imagine to be real, for reality itself.

Social psychologists call this ‘naive realism.’ It means that your experience of something is the final word on that thing – if somebone made you mad, it’s because they’re a bad person, or if you just got fired, that means you must be useless at your job.

These self-narratives are especially self-limiting – or even self-destructive – and this kind of rumination is a key component of depression and anxiety disorders.

Rehashing negative experiences likely has its roots in human evolution. Your brain remembers difficult times as significant experiences and rumination tends to replay negative memories and all the negative emotions that go with them. Recycling the same thoughts and associated emotions is unproductive because it doesn’t offer any insight into cause and effect; in other words, what those events mean as part of the bigger picture.

We should learn to create psychological and emotional distance between these events and ourselves. We should learn to put things in perspective. If you’re constantly going over an argument with your partner in your head, you’re not really getting anywhere.

This repetitive pattern can spiral into depression, where every event becomes a reflection of your negative self-worth. If you’re looking for a negative interpretation of events, you’re more than likely going to find one. These thought processes border on paranoia – sufferers always imagine that the worst interpretation is the truth. If the pattern continues, you begin to impose your own negativity on similar events. Before you know it, you have established a cycle from which it is difficult to break free.

Rumination encourages anxiety, which in turn can lead to depressive thoughts. People who ruminate a lot are less forgiving of themselves, tend to abuse alcohol or drugs more, take more risks and are at greater risk of suicidal thought.

As early as infancy, we struggle to make sense of the world, and by the time language develops, the self-narrative process has already been interwoven with our sensory experience – even before episodic memory starts to form. The narrative process is part of the cognitive process, so thoughts become integrated into our initial experience of the world.

Self-narrative, language use, and sensory experience are all interwoven. Everyone has a voice in their head which comments on everything. This is so completely embedded in our experience of the world that we don’t even recognise it.

Millions of years of evolutionary pressure is telling us how and what to think – the ancestor that didn’t think and worry about storing enough food for winter or what went wrong on the last hunt didn’t live long enough to pass on his genes to become your ancestor. Attention is a needs-based mental function –but in addition to noticing opportunities, it also highlights threats.

Many of the leading treatments for anxiety and depression involve methods for establishing a new relationship with a person’s predisposition to finding threats, analyzing weaknesses and self-narratives.

Both meditation and cognitive behaviour therapy train patients not to believe everything they think about. Meditation has been shown to reduce rumination and depression. CBT can also help with depression, generalized anxiety and panic disorders. The combination of meditation and CBT may be especially effective – mindfulness-based CBT can significantly reduce relapse in people who have recovered from depression.

With CBT, self-narratives are challenged through reappraisal. This can be accomplished by working with a therapist – two people in search of a solution – or in a group, or even by clients themselves. Once clients understand the mechanism, they can learn to self-diagnose and change their narrative so it becomes more positive, more upbeat. Combining treatments with hypnosis – even just the relaxation techniques – and clients will become more focused on positive thoughts and emotions.

By rethinking a given situation, possibly examining whether your ideas about what happened are truly accurate or what other’s intentions might have been, rethinking the narrative and adjusting your emotional reaction will change your perspective.

The main reason CBT works so well for people heavy on rumination is because they’ve already spent much time interrogating their own thoughts. With reappraisal, they can use that same internal investigation skill and turn it into something that breaks down barriers, rather than creating them.

The kind of mental processes used in reappraisal include the ability to focus on certain sensations and ignore others and the ability to sense what you and others are feeling in a given situation. When these processes work in concert, you can revise your assumptions and see situations in a new light. Clients are sometimes surprised that this happens quickly and spontaneously.

Clients should understand that all emotions are subjective and that all experiences are subject to some degree of interpretation. It’s all about getting beyond the imagination, where you assume that how or why you think something happened is the truth of the matter.

With techniques like mindfulness and CBT, individuals are more easily able to see that the narratives that structure their lives can be changed to reflect more positive thought processes and emotions. The rest is surprisingly easy.


Copyright Andrew Newton 2017. All rights reserved.