A region of the brain linked with risk-taking has been identified by scientists, who say it could explain why some people are more likely to smoke and drink.
A team of neurologists from the University of Zurich found major functional and anatomical distinctions among those who are likely to smoke, use alcohol or drugs, speed, or have many sexual partners when compared to more cautious people.
For the study the Swiss team examined 25,000 people and found a direct relationship between differences in brain anatomy and propensity to take risks.
Distinct characteristics were found in regions of the brain responsible for controlling happy hormones like dopamine, memory storage and in managing self-control.