Neuroscientist Tali Sharot looks at the human brain’s tendency toward optimism. Psychologists have long been aware that most people maintain an often irrationally positive outlook on life. In fact, optimism may be crucial to our existence. The Optimism Bias: A Tour of the Irrationally Positive Brain looks at experiments, research, and findings in cognitive science that help explain the biological basis of optimism. Sharot examines how the brain generates hope and what happens when it fails.