Researchers at the University of Nottingham in the U.K. are testing their theory that brain structure may biologically predispose some individuals to addiction, Science Daily reported Oct. 22.

The study will look at the impact that abnormalities in the frontal cortex -- the part of the brain involved in decision making -- have on a person's odds of developing an addiction. Individuals with such flaws may be less able to assess the risks of drug use and more apt to make bad decisions, researchers said.

"Evidence suggests that a large percentage of the population try drugs but only a small proportion of experimental users -- roughly about 15 percent -- will make the transition to full-blown addiction," said researcher Lee Hogarth. "Our study will move us a step closer to understanding why some people can use drugs recreationally without becoming hooked, while others will go on to develop clinical dependence."

The scientists plan to compare students and adults who self-report as social and daily smokers. The researchers will measure participants' brain activity through MRI technology and by linking an unpleasant noise (as a negative consequence) with obtaining cigarettes to see if the subjects smoke, regardless -- an indication that they may be dependent.

"There is currently a debate as to whether addicts are responsible for their addictive behavior, which has implications for the funding of their healthcare and treatment," Hogarth said. "If our hypothesis proves correct, we would argue that addicts are intentionally choosing to take drugs, rather than being controlled, like robots, by urges beyond their control. However, this does not mean that addicts are morally culpable for their choices, because they cannot help being vulnerable to a distortion of the neural system that computes their choices."