Risk-taking can manifest itself in a socially-acceptable fashion such as sky-diving or rock-climbing or in less acceptable ways such as antisocial behaviour or substance abuse. Researchers from the University of Kentucky recruited two sets of volunteers using psychological tests and questionnaires. One set were high-sensation seekers (risk-takers) and the other were low-sensation seekers who were more risk-averse. The researchers gave the participants a brain scan while showing them images some of which were neutral and some of which were arousing (either erotic or violent). When the high-sensation seekers viewed the arousing pictures there was increased activity in a part of the brain called the insula which is associated with addictive behaviour. However, when the low-sensation seekers looked at the same photographs they had more activity in their frontal cortex, an area of the brain involved in emotional regulation. The researchers concluded that the high-sensation seekers were more easily aroused and less able to regulate their emotions than the low-sensation seekers.
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