The symptom of depression most people don't even notice

There are a number of common signs of depression that often go unnoticed. On many occasions we fail to recognise the warning signs in our own lives, and it's take a friend or family member to reach out to point them out.

Weight loss, loss of appetite, loss of sex drive, wavering concentration and difficulty enjoying things: these are all fairly well-known symptoms that can be linked to depression.

But there’s one symptom that hasn’t had quite as much attention, and it’s called hindsight bias.

Depressed people are more likely to project their cloudy outlook onto the past, rather than glorify the good old days, like we're more likely to do.

New research from Heinrich Heine Universität Düsseldorf and University of Portsmouth tested more than 100 students with mild to severe depression. They were asked to imagine themselves in a number of scenarios with positive or negative outcomes, and the researchers measured their level of hindsight bias.

They found a link between hindsight bias and the severity of a person's depression.

Dr Hartmut Blank, from the University of Portsmouth, said:

Depression is not only associated with a negative view of the world, the self and the future, but we now know with a negative view of the past.

Everyone is susceptible to hindsight bias, but it takes on a very specific form in depression. While non-depressed people tend to show hindsight bias for positive events but not negative events, people with depression show the reverse pattern.

He explained that the bias contributes to making the patient feel more negative.

Making things worse, depressed people also see negative event outcomes as both foreseeable and inevitable -- a toxic combination, reinforcing feelings of helplessness and lack of control that already characterise the experience of people with depression.

Everyone experiences disappointment and regret from time to time and doing so helps us adapt and grow and to make better decisions. But people with depression struggle to control negative feelings and hindsight bias appears to set up a cycle of misery.

We have shown hindsight bias in people who are depressed is a further burden on their shoulders, 'helping' to sustain the condition in terms of learning the wrong lessons from the past.

If you are feeling vulnerable, upset or depressed there is always someone available to talk and help.

You can contact the Samaritans 24-hours a day for free via their website or phone line 116123

If you're LGBTQI and in need of someone to talk to, Switchboard LGBT offer advice and help every day from 10am to 10pm on their website and on 0300 330 0630

Alternatively, if you suspect a young person might be feeling suicidal, you can call Childlinefor help and advice on 0800 111

HT Medical Daily and the NHS

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