Source of ‘optimism’ found in the brain

Two regions of the brain linked to optimism have been discovered by researchers, newscientist.com reported. Brain scans obtained using functional magnetic resonance imaging (fMRI) revealed that reflecting on both past and future events activated the amygdala and the (rACC) areas, both of which sit deep in the middle of the brain. However, positive events – and particularly those imagined in the future – elicited a significantly bigger brain response in these regions than reflecting on negative events. The identification of the sites that signal positive thinking could shed light on the causes of depression, they say.

The US team says that the act of imagining a positive future event – such as winning an award or receiving a large sum of cash – activates two brain areas known as the amygdala and the rostral anterior cingulated cortex (rACC). The finding lends weight to earlier studies that suggested these brain regions malfunction in depression and hint at new ways of diagnosing the disorder.

Elizabeth Phelps at the New York University, US, and colleagues measured how optimistic 15 volunteers were using a standard questionnaire. The researchers then asked these subjects to lie in a brain scanner and reflect on one of a number of potential scenarios.

For example, in one part of the trial, subjects followed specific instructions to recall a negative event in the past, such a funeral attended in the past five years. In another part of the experiment they had to imagine what it would be like to be involved in a car crash in the near future. At other points in the study subjects had to reflect on positive events such as winning an award in the past or receiving a large sum of cash in the future.