A study in England in 2011 reported that most of us have a bias towards positivity.
“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.”
"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."