Impulsivity-Related Problem Drinking Decreases Greatly for 18 To 25-Year-Olds - Science Daily Personality traits associated with impulsivity normally decrease during emerging and young adulthood, and these decreases are associated with reduced substance use. A new study of "trajectories" of impulsivity and their association with problem alcohol use has found that the 18-to-25-years-of-age group exhibited the largest declines in impulsivity as well as the sharpest decreases in alcohol consumption. "Traits related to impulsivity, such as undirectedness or 'reverse-scored conscientiousness,' tend to normally decrease from late adolescence into early adulthood, approximately from ages 18 to 35," explained Andrew K. Littlefield, a doctoral student in clinical psychology at the University of Missouri and corresponding author for the study. "Many researchers and clinicians think of personality as an incredibly stable construct that does not change across time, however, these findings provide clear evidence that at least some individuals undergo significant changes in impulsivity across time," he said. "Future studies could examine why some individuals make significant changes in impulsivity across time whereas other individuals' level of impulsivity remains relatively stable. Identifying factors that enhance or inhibit seemingly beneficial changes in personality may inform treatment approaches that could facilitate decreased impulsivity." The study was funded by the National Institute on Alcohol Abuse and Alcoholism.