Excerpt: In a study published online last month in The Journal of Psychiatric Research, Janine D. Flory, a psychologist at the Mount Sinai School of Medicine in Manhattan, led a team of investigators who studied 351 healthy adults and 70 others with impulse-related disorders like antisocial and borderline personality disorders. The participants took a battery of tests to measure inhibition, appetite for risk and the inclination to plan. Analyzing the responses to questions intended to gauge thrill seeking like, “”I like to explore a strange city or section of town by myself, even if it means getting lost,”” and, “”I like to try foods I’ve never tried before,”” the researchers found that an appetite for risk was associated with smoking in both groups. But in the healthy volunteers, the appetite was also associated with higher education. In previous studies, healthy risk seekers scored highly for curiosity and openness to new experiences. On measurements of instinctive planning – “”I am better at saving money than most people”” and “”I hate to make decisions based on first impressions”” – the researchers found that less deliberative habits were related to heavy drinking in the healthy group and the troubled group. In cases with personality disorders, deficits in planning were also associated with a history of suicide attempts. The combination of sensation seeking and lack of deliberation characterizes millions of healthy people but appears to be extreme in those whose impulsivity leads to chronic trouble or mental illness, Dr. Flory said.