Personality is partly determined by the shape of our brains, a new study has found.
In neurotic people prone to mood changes and psychiatric disorders, the outer layer of the brain is thicker and less wrinkly, according to the research.
Individuals with 'open' personalities linked to curiosity and creativity show an opposite pattern. The outer layer, or cortex, is thinner and more folded in certain regions with a greater surface area, say scientists.
The new findings show that personality may be the result of the brain's general structure as well as its internal circuitry. Researchers focused on the cortex, where the higher functions that make us human are centred.
Dr Luca Passamonti, a member of the team from Cambridge University, said: "Evolution has shaped our brain anatomy in a way that maximises its area and folding at the expense of reduced thickness of the cortex.
"It's like stretching and folding a rubber sheet - this increases the surface area, but at the same time the sheet itself becomes thinner."