Humans have a natural tendency to look at the silver lining, to see beyond facts and rely on hunches to get things done. A new study has discovered that a certain area in the brain makes us all optimistic.

Researchers from University College, London and colleagues have found that magnetic pulses to this region make people less optimistic and more ready to look at life objectively.

The left and right inferior frontal gyrus (IFG) have been suspected of being involved in the good and bad news processing; with the left processing good news and the right processing bad news. The reason why humans are sometimes hopelessly optimistic is that the right side of the inferior frontal gyrus doesn't do its job properly leaving the left side to take control.

To understand the workings of this region, the researchers selectively inhibited activity in either left or right inferior frontal gyrus of the brains of 30 volunteers using magnetic pulses. Another set of participants also received magnetic pulses, but not in this region and so acted as a control set.

All participants were then asked to rate the probability of bad things happening in their life. The researchers then read out the actual likelihood of bad things happening to them according to actual evidence. Volunteers were then asked to rate the occurrence of bad events in their lives again after knowing the actual odds.

People who received magnetic pulses to the left side of the brain were more likely to think logically about occurrence of a bad event. The researchers say that how the brain filters out the bad news and why it does so remains a mystery. However, one possible explanation is that by suppressing negativity, humans can explore new regions and take more risks.

"So much of the work on psychological biases over the decades has been correlational. Here we have a rare example of a direct manipulation experiment. This is a great step forward and promises to open up whole new avenues for research in this area," said Dominic Johnson, a political scientist from the University of Oxford, reports The Scientist. Johnson wasn't part of the present study.

The study may help people treat depressed people as disrupting activity in the right inferior frontal gyrus can lead to people getting better at being optimistic.

"If you start off in depressed individuals, my hypothesis would be that disrupting the right IFG would create a bias that isn't there," said Tali Sharot from University College, London, and one of the study authors, reports The New Scientist.

The study was published in the journal PNAS.