A new study shows that a reason why optimists retain a positive outlook even in the face of reality could be that the brain rejects bad news. The study published in Nature Neuroscience adds that in some people, anything negative is practically ignored - with them retaining a positive world view.
The authors said optimism did have important health benefits. A study on nearly 100,000 women showed a lower risk of heart disease and death in optimists. Scientists at University College London said about 80% of people were optimists, even if they would not label themselves as such. They rated 14 people for their level of optimism and tested them in a brain scanner or functional magnetic resonance imaging (fMRI).
Each was asked how likely 80 different “bad events” - including a divorce, having their car stolen, getting fired from their job, developing Parkinson's disease or having cancer - were to happen. They were then told how likely this was in reality. At the end of the session, the participants were asked to rate the probabilities again. There was a marked difference in the updated scores of optimists depending on whether the reality was good or bad news.
Dr Tali Sharot, lead researcher, gave the example of the risk of cancer being set at 30%. If the patient thought their risk was 40%, then at the end of the experiment they downgraded their own risk to about 31%, she said. However, if the patient originally thought their risk was 10%, they only marginally increased their risk - they “leaned a little bit, but not a lot”.
When the news was positive, all people had more activity in the brain's frontal lobes, which are associated with processing errors. With negative information, the most optimistic people had the least activity in the frontal lobes, while the least optimistic had the most. It suggests the brain is picking and choosing which evidence to listen to.
Dr Sharot explained, “Smoking kills messages don't work as people think their chances of cancer are low. The divorce rate is 50%, but people don't think it's the same for them. There is a very fundamental bias in the brain.”
Dr Chris Chambers, neuroscientist from the University of Cardiff, said, “It's very cool, a very elegant piece of work and fascinating. For me, this work highlights something that is becoming increasingly apparent in neuroscience that a major part of brain function in decision-making is the testing of predictions against reality - in essence all people are 'scientists'. And despite how sophisticated these neural networks are, it is illuminating to see how the brain sometimes comes up with wrong and overly optimistic answers despite the evidence.”
Commenting on the study, Dr John Williams, Head of Neuroscience and Mental Health at the Wellcome Trust, said, “Being optimistic must clearly have some benefits, but is it always helpful and why do some people have a less rosy outlook on life? Understanding how some people always manage to remain optimistic could provide useful insights into happens when our brains do not function properly.”
“Seeing the glass as half full rather than half empty can be a positive thing -- it can lower stress and anxiety, and be good for our health and well-being,” Dr. Sharot said. “But it can also mean that we are less likely to take precautionary action, such as practicing safe sex or saving up for retirement,” she said. Many experts, she pointed out, believe that the financial crisis that began in the fall of 2008 was in large part caused by wishful thinking about rising property values and the ability to play down or dismiss levels of debt.
“The negative aspect [of optimism] is that we underestimate risks.”
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